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<strong>Glaucoma</strong> - <strong>II</strong><br />
<strong>Free</strong> <strong>Papers</strong>
Contents<br />
Contents<br />
GLAUCOMA - <strong>II</strong><br />
Health Literacy and Other Barriers to Follow-up after Initial Diagnosis of<br />
<strong>Glaucoma</strong> in South Indian .............................................................................. 349<br />
Dr. Manju R Pillai, Dr. Saket Surinder Patel, Dr. Krishnadas S R, Mr. Vinayaka Moorhy,<br />
Mr. Heber A<br />
Correlation of OCT Measured Retinal Nerve Fibre Layer Thickness with<br />
Refractive Status of the Eye............................................................................ 354<br />
Dr. S V Singh, Dr. Pankaj Kataria, Dr. Dhull chand Singh, Dr. Manisha Nada,<br />
Dr. Vijayender Kumar Dhull<br />
Family Screening of POAG and PACG Patients: The Help of Family <strong>Glaucoma</strong><br />
Screening Project ............................................................................................ 358<br />
Dr. Devendra Maheshwari, Dr. Neelam Pawar, Dr. Ramakrishnan R, Dr. Mohideen<br />
Abdul Kader, Dr. Ankit Gupta<br />
Peripapillary Retinal Nerve Fibre Layer Thickness in high Myopia: Thinner<br />
than the Normal?.............................................................................................. 362<br />
Dr. Dipali R Satani, Dr. Surohi Shah, Dr. Amit Patel, Dr. Shwetambari Singh<br />
Inter-Observer Variation for Non-Simultaneous Stereo Disc Photo Pairs with<br />
A Regular Fundus Camera............................................................................... 365<br />
Dr. Sushma Tejwani, Dr. Jyoti Matalia, Dr. Bhujang Shetty K<br />
Role of Intravitreal Avastin in Neovascular <strong>Glaucoma</strong> ............................... 367<br />
Dr. S Sujata, Dr. A Prabhakaran, Dr. C A Nelson Jesudasan<br />
Evaluation of Quality of Life in Elderly POAG Patients by Using the GQL-15<br />
Questionnaire ................................................................................................... 370<br />
Dr. Devendra Maheshwari, Dr. Neelam Pawar, Dr. R Ramakrishnan, Dr. Mohideen<br />
Abdul Kader, Dr Ankit Gupta<br />
Association of MTHFR 677C>T Polymorphism with Primary Open Angle<br />
<strong>Glaucoma</strong> in North Indian Population.............................................................374<br />
Dr. Abhishek Chandra, Dr. Abhishek Dixit, Dr. Ritu Barnwal, Dr. Om Prakash Singh<br />
Maurya, Dr. Mousumi Mutsuddi, Dr. Akhtar Ali<br />
Factors Affecting Compliance in <strong>Glaucoma</strong> Therapy in Eastern Indian<br />
Population.......................................................................................................... 378<br />
Dr. Prasanta Kumar Nanda, Dr. Sumita Mohapatra<br />
Optic Disc Size and its Correlates in High Myopia in Central India........... 381<br />
Dr. Vinay Kumar Nangia B, Dr. Rajesh Gupta, Dr. Anshu Khare, Dr. Ajit Kumar Sinha<br />
Effect of Intraocular Bevacizumab on Visual Acuity and Intraocular Pressure<br />
in Neovascular <strong>Glaucoma</strong> ............................................................................... 384<br />
Dr. Pooja Prem Aggarwal, Dr. Balekudaru Shantha<br />
Biometry in Primary Angle Closure <strong>Glaucoma</strong> Subjects and in a Population<br />
Based Study...................................................................................................... 388<br />
Dr. Ajit Kumar Sinha, Dr. Vinay Kumar Nangia B, Dr. Rajesh Gupta, Dr. Shubhra<br />
Agarwal, Dr. Karishma Bhate<br />
AGV in Refractory <strong>Glaucoma</strong>-Outcome, Complications and Management of<br />
Complications—Single Surgeons Experience.............................................. 391<br />
Dr. Arijit Mitra, Dr. Ramakrishnan R, Dr. Mohindeen Abdul Kadar P M, Dr. Anup Das,<br />
Dr. Ashish Kumar<br />
Neovascular <strong>Glaucoma</strong> – IOP Control by Avastin and Subsequent<br />
Trabeculectomy with Mitomicin-C.................................................................. 397<br />
Dr. Tanuja Kate, Dr. Jyoti Singhyai, Dr. Navita Mittal, Dr. Rajiv Choudhary
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GLAUCOMA - <strong>II</strong><br />
Chairman: Dr. S R Krishna Das; Co-Chairman: Dr. B N Gupta<br />
Convenor: Dr. P K Mohanty; Moderator: Dr. Sumit Choudhury<br />
Dr. MANJU R PILLAI: MBBS (1992), P S G Institute of Medical Sciences,<br />
Coimbatore- Bharathiar University; DO (1995), Aravind Eye Hospital, Madurai,<br />
M G R Medical University; DNB (1999). Recipient of Top Poster Award-<br />
International Congress on <strong>Glaucoma</strong> Surgery 2010. Presently, Consultant,<br />
<strong>Glaucoma</strong> Services, Aravind Eye Hospital, Madurai.<br />
E-mail: manju@aravind.org<br />
Health Literacy and Other Barriers to Follow-up<br />
after Initial Diagnosis of <strong>Glaucoma</strong> in South<br />
Indian<br />
Dr. Manju R Pillai, Dr. Saket Surinder Patel, Dr. Krishnadas S R,<br />
Mr. Vinayaka Moorhy, Mr. Heber A<br />
Communication between patient and physician is very important in the<br />
treatment of glaucoma. Adherence to medications requires the patients<br />
understand the instructions to administer their eye drops. Hence health<br />
literacy means the degree to which individuals have the capacity to obtain,<br />
process and understand the basic health information and services needed<br />
to make appropriate health decisions. Functional health literacy defines the<br />
ability to apply reading and numeracy skills in health care. They include the<br />
ability to 1) Read the consent form, 2) understand oral and written information<br />
given in the hospital 3) act on necessary procedures and directions. Patients<br />
with low health literacy and chronic diseases have less knowledge of their<br />
disease and treatment.<br />
Muir and associates observed a positive correlation between low health<br />
literacy and adherence to glaucoma medications. Muir and associates also<br />
found that lower health literacy do not appear to have worse overall VRQoL,<br />
but worse literacy is associated with increased dependency.<br />
In India literate men are 60.02 %, literate female is 39.97%. Illiteracy accounts<br />
for 41.80% men and 58.19% females. In Tamil Nadu literate men accounts for<br />
56.25% and females 43.71%., Illitearcy accounts for 59.26 % males and 60.73 %<br />
females.<br />
To assess what association may exist between health-literacy 1-3 and other<br />
social and demographic factors and the probability of return for follow-up<br />
in newly identified glaucoma patients in South India. Low adherence in<br />
glaucoma patients leads to increased intraocular pressure, optic nerve damage<br />
and blindness.<br />
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69th AIOC Proceedings, Ahmedabad 2011<br />
MATERIALS AND METHODS<br />
We conducted a prospective cohort study of 250 Tamil-speaking individuals<br />
enrolled at the time of newly diagnosed glaucoma at the Aravind Eye Hospital<br />
in Madurai, India. Inclusion criteria of patients were: 1) newly diagnosed<br />
primary glaucoma patients 2) must live within 50 miles radius from Aravind<br />
3) more than 18 years of age, 4) Must have better vision 6/36.<br />
Tamil translations of two validated literacy assessments were used to evaluate<br />
health-literacy: “Rapid Assessment of Adult Literacy in Medicine” (REALM) 4<br />
and “Test of Functional Health Literacy in Adults” (TOFHLA). 5 An additional<br />
oral questionnaire was administered to assess age, gender, level of education,<br />
socioeconomic status, marital status, distance and mode of transportation<br />
used to attend clinic appointments, and need for an escort.<br />
<strong>Glaucoma</strong> therapy was initiated on the date of enrollment, and follow-up<br />
was scheduled. Follow up dates were given to all patients before leaving the<br />
hospital. Approximately 1 week to 2 months later at the physician’s discretion<br />
and subjects were followed for one year post-diagnosis. This analysis evaluated<br />
factors associated with failure to return for initial follow-up examination.<br />
In the follow up visits, current visual acuity, intra ocular pressure and drugs<br />
prescribed were recorded. Follow up oral surveys were also conducted to find<br />
out about use of medications, and its dosage.<br />
Patients who had their follow ups missed, had a reminder send to them as a<br />
post card two weeks after their scheduled visit. Home visit was conducted for<br />
all patients who were not adherent to the follow up dates.<br />
Patients who returned after field visits remained in the study. Persons who did<br />
not return for one month even after the field visit were sent a second reminder<br />
card to inform about their follow up.<br />
RESULTS<br />
In univariate analysis, REALM score with literacy ≤ grade 3 (47.1% vs. 64.5%,<br />
p=0.01), subjective illiteracy (47.8% vs. 63.16%, p=0.02), and lower TOFHLA score<br />
(28.3 vs. 39.4, p=0.04) were associated with a lower probability of returning for<br />
follow-up. Subjects who failed to return also subjectively had more difficulty<br />
finding time (p=0.01) and money (p=0.02) to visit the doctor than those who<br />
returned for follow-up, but did not have longer travel times (2.06 hrs vs. 1.94<br />
hrs, p=0.43) or higher travel costs (Rs 22.6 vs. Rs 23.2, p=0.81). Subjects who<br />
followed-up were more likely to have a higher Kuppuswamy socioeconomic<br />
status score (7.68 vs. 9.19, p=0.01), be married (41.3% vs. 57.8%, p=0.049), and<br />
have either primary angle-closure glaucoma (PACG) or pseudoexfoliative<br />
glaucoma (p=0.003).<br />
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Multivariate logistic regression analysis identified REALM score ≤grade<br />
3 (p=0.05) as being independently associated with a higher risk of failure<br />
to return for follow-up and a diagnosis of primary angle-closure glaucoma<br />
(p=0.007) as being independently associated with a higher probability of<br />
follow-up.<br />
Variable<br />
Missed visit<br />
Yes(137) No(113) p-value<br />
n % n %<br />
Age Mean(SD) 60.1(9.9) 59.3(10.9) 0.55<br />
Sex<br />
Male 90 57.0 68 43.0 0.43<br />
Female 47 51.1 45 48.9<br />
Pressure Left Eye 24.4(10.1) 22.6(10.1) 0.16<br />
Pressure Right Eye 23.5(9.7) 22.2(9.4) 0.29<br />
Score sum Mean(SD) 9.2(5.1) 7.7(4.2) 0.012*<br />
Socioeconomic Status<br />
Lower 11 45.8 13 54.2<br />
Upper Lower 86 51.2 82 48.8<br />
Lower Middle 26 25.7 9 74.3 0.02*<br />
Upper Middle 11 55.0 9 45.0<br />
Upper 3 100.0 0 0.0<br />
Literacy<br />
Yes 72 63.2 42 36.8 0.016*<br />
No 65 47.8 71 52.2<br />
Income Mean(SD) 4300.7(4264.5) 3669.4(3895.7) 0.23<br />
Problem with Time for<br />
Dr appointment<br />
None 71 65.1 38 34.9<br />
Somewhat a problem 63 47.4 70 52.6 0.011*<br />
Significant problem 3 37.5 5 62.5<br />
Marital Status<br />
Yes 118 57.8 86 42.2 0.049*<br />
No 19 41.3 27 58.7<br />
Travel time to the hospital<br />
Mean(SD) 1.94(1.14) 2.06(1.20) 0.43<br />
Travel cost<br />
Mean(SD) 23.2(17.8) 22.6(17.8) 0.81<br />
Feels follow-up important<br />
Yes 132 55.5 106 44.5 0.39<br />
No 5 41.7 7 58.3<br />
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Cost of Doctor<br />
None 99 59.6 67 40.4 0.02*<br />
Somewhat a problem 35 47.3 39 52.7<br />
Significant problem 3 30.0 7 70.0<br />
Realm Grade Level<br />
3rd or Less 66 47.1 74 52.9<br />
4th to 6th Grade 5 83.3 1 16.7 0.01*<br />
7th to 8th Grade 4 66.7 2 33.3<br />
High School 62 63.3 36 36.7<br />
Numeracy weighted Total<br />
Mean (SD) 20.7(22.2) 15.1(21.5) 0.043*<br />
Reading Comprehension<br />
Grand Total<br />
Mean(SD) 18.7(21.3) 13.3(19.7) 0.0407*<br />
Mean(SD) 39.4(42.9) 28.3(40.8) 0.0393*<br />
Health Literacy Adequate<br />
Yes 54 61.4 34 38.6 0.08<br />
No 83 51.2 79 48.8<br />
ICD9 Code<br />
POAG 74 47.7 81 52.3<br />
PACG 26 78.8 7 21.2 0.003*<br />
PXFG 37 59.7 25 40.3<br />
*significant<br />
Variable<br />
Odds ratio<br />
95% Confidence interval p-value<br />
PACG 3.51(1.4, 8.7) 0.007*<br />
PXFG 1.73(0.94, 3.2) 0.080<br />
Time for Doctor 0.63(0.38, 1.04) 0.069<br />
Low Grade Level 0.58(0.33, 1.01) 0.053<br />
Comments<br />
Muir and Lee has certain suggestions for effective education with poor literacy<br />
skills.<br />
Improving communication with patients is a good way to address this problem.<br />
Speaking slowly improves the communication. It is also essential to use plain<br />
language with less medical terms. It is also good practice to assess the patient’s<br />
current knowledge and to link new information to the existing knowledge.<br />
Physician should also demonstrate and ask the patient to demonstrate eye<br />
drop instillation technique. Creating good educational material with few<br />
important points, limiting dense text and using visuals are the way to provide<br />
good information.<br />
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69th AIOC Proceedings, Ahmedabad 2011<br />
Considering audio and / video materials is also good in counseling patients<br />
with poor literacy skills.<br />
In this population, illiteracy is a significant risk factor for failure to return<br />
after initial diagnosis of glaucoma. Use of the REALM assessment is a quick,<br />
effective method to screen for illiteracy and may be used as part of a larger<br />
screening for poor follow-up. Asking patients about their difficulty in finding<br />
the time or money to visit the doctor also screens for patients at risk for poor<br />
follow-up. It is unclear why patients with PACG were more likely to return;<br />
this may be due to a patient perception that their disease is more serious<br />
because of the need for laser treatment. Eye care providers should assess<br />
health literacy in all newly diagnosed patients and create different focused<br />
counseling strategies aimed at those with lower health literacy.<br />
REFERENCES<br />
1. Lee B W, Sathyan P, John R, Singh K, Robin AL. Predictors of and Barriers<br />
Associated with Poor Follow-up in Patients With <strong>Glaucoma</strong> in South India. Arch<br />
Ophthalmol 2008;126:1448-54.<br />
2. Juzych MS, Randhawa S, Shukairy A, Kaushal P, Gupta A, Shalauta N. Functional<br />
health literacy in patients with glaucoma in urban settings. Arch Ophthalmol 2008;<br />
126:718-24.<br />
3. Muir KW, Santiago-Turla C, Stinnett SS, Herndon LW, Allingham RR, Challa P,<br />
Lee PP. Health literacy and adherence to glaucoma therapy. Am J Ophthalmol 2006;<br />
142:223-6.<br />
4. Davis TC, Long SW, Jackson RH, et al. Rapid estimate of adult literacy in medicine:<br />
a shortened screening instrument. Family Medicine 1993;25:391-5.<br />
5. Nurss J, Parker R, Williams M, Baker D. TOFHLA: Test of functional health literacy<br />
in adults (Technical Report). Snow Camp, NC: Peppercorn Books and Press, 2001.<br />
Correlation of OCT Measured Retinal Nerve Fibre<br />
Layer Thickness with Refractive Status of the Eye<br />
Dr. S V Singh, Dr. Pankaj Kataria, Dr. Dhull Chand Singh, Dr. Manisha<br />
Nada, Dr. Vijayender Kumar Dhull<br />
Retinal Nerve Fibre Layer (RNFL) examination is important in diagnosing and<br />
monitoring the progression of various retinal diseases. 1 Various investigational<br />
modalities like Retinal Nerve Fibre layer Analyzer (RNFA), Scanning Laser<br />
354<br />
Dr. S V SINGH: MS (1984), Govt. Medical College, Rohtak,<br />
Presently Senior Professor at Regional Institute of Ophthalmology, PGIMS,<br />
Rohtak. Hon. General Secretary of Haryana Ophthalmological Society.<br />
Phone: (01262) 212425.
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Ophthalmoscope (Gdx and GDx with variable corneal compensation) and<br />
Optical Coherence Tomography (OCT) are used to measure the RNFL<br />
thickness. OCT provides an absolute cross sectional measurement of retina<br />
from which RNFL thickness is calculated. However, OCT measured RNFL<br />
thickness has been found to correlate with that measured with scanning laser<br />
ophthalmoscope and the Heidelberg Retinal Tomography (HRT).<br />
MATERIALS AND METHODS<br />
This was a prospective and unmasked study. Myopic, hypermetropic and<br />
emmetropic subjects presenting to our Regional Institute of Ophthalmology<br />
OPD from jan 2009 to dec 2010 were included in this study.<br />
A prior informed consent was taken. Each subject underwent a complete<br />
ophthalmologic examination including best corrected visual acuity (BCVA),<br />
intraocular pressure (IOP) measured by slit lamp mounted Goldmann<br />
applanation tonometer, gonioscopy, slit lamp examination, stereoscopic fundus<br />
examination using 90D lens to exclude any posterior segment pathology and<br />
ret i nal ner ve fiber layer evaluat ion by Opt ical Coherence Tomog raphy.<br />
Subjects with history of intraocular surgery, glaucoma, diabetes, hypertension,<br />
any media opacities(corneal and lenticular) or any posterior segment pathology<br />
(optic atrophy, disc edema) were excluded from the study<br />
Subjects included in this study were emmetropes, axial myopes and axial<br />
hypermetropes (with refractive error ≤ ±6D) with age 10 yrs or more.<br />
After making above exclusions, 150 patients, included in this study, were<br />
divided into three groups of 50 each with emmetropia (group 1), myopia<br />
(group 2) and hypermetropia (group 3).<br />
PROCEDURES<br />
First of all baseline examination of the myopic and hypermetropic subjects<br />
like Best Corrected Visual Acuity (BCVA), Automated Refraction, Fundus<br />
examination (slit-lamp biomicroscopy and Indirect Ophthalmoscopy to rule<br />
out any posterior segment pathology) and Goldmann applanation tonometry<br />
were done.<br />
Optical Coherence Tomography<br />
OCT machine (RTVue, model- RT100 of OPTOVUE inc. FREMONT,<br />
CALIFORNIA) was used for measuring RNFL thickness and software version<br />
4.0 was used for analysis. The RNFL scan pattern completes four circular scans<br />
in 0.16 sec. at a diameter of 3.45mm, targeted around the optic nerve head.<br />
These scans are averaged and the result is presented within the normative<br />
range parameters. The presented display is an averaged result (average of 4<br />
scans).<br />
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69th AIOC Proceedings, Ahmedabad 2011<br />
Pupil of each eye was dilated with tropicamide 1% upto minimum pupillary<br />
diameter of 5mm. After aligning the eye to be examined by using internal<br />
fixation target, scanning was performed.<br />
RESULTS<br />
Of the 150 subjects, there were 50 emmetropes, 50 Hypermetropes and 50 myopes<br />
with refraction ranging from+ 6D to -6D spherical equivalent. There were equal<br />
number of males and females with mean age of 21±5 yrs. However we also analyzed<br />
difference between the mild and moderate refractive errors in myopic eyes. Mean<br />
± Standard Deviation for RNFL thickness in inferior, superior, nasal and temporal<br />
quadrants in emmetropic patients were 150.5 ± 14µ, 141.6 ± 12µ, 89.6 ± 12µ, and 80.3<br />
± 10µ respectively. Mean RNFL thickness was highest in inferior quadrant followed<br />
by superior, nasal and temporal quadrant.<br />
Mean ± Standard Deviation for RNFL thickness in inferior, superior, nasal and<br />
temporal quadrants in hypermetropes were 160 ± 15µ, 152.5 ± 12µ, 94.8 ± 12µ,<br />
81.68 ± 11µ respectively. Increased RNFL thickness was observed in hypermetropic<br />
patients as compared to emmetropes, myopes and follows the ISNT rule. Myopes<br />
had less RNFL thickness than emmetropes and hypermetropes and did not follow<br />
the ISNT rule (inf- 130.1 ± 15.34µ, sup- 118.3 ± 13µ, nasal 63.15 ± 12µ, temp- 78.94 ± 11µ.<br />
Differences in RNFL thickness amongst myopes, hypermetropes and emmetropes<br />
were statistically significant (p
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of myopia as high myopes are associated with more RNFL thinning. 5 In our<br />
study, it has been found that RNFL thinning is also associated with mild and<br />
moderate myopia. Kelly conducted study in emmetropic and high myopic<br />
patients and he found that mean RNFL thickness in myopia was 80 microns as<br />
compared to 108.8 microns in emmetropes. 6<br />
As not much of the studies have been conducted on the RNFL thickness<br />
measurement in hypermetropes and whatever has been conducted poses a<br />
controversial issue of whether RNFL thickness increases or decreases with<br />
hypermetropic errors. In this study we found increase in RNFL thickness in<br />
hypermetropes as compared to emmetropes and it also followed the ISNT rule.<br />
Kremmer found reduction in the average RNFL thickness in both myopes and<br />
hypermetropes as compared to controls. 7 However, study conducted by Sang<br />
Hoon concluded that in shorter eyes, there was a tendency toward hyperopia,<br />
a steeper cornea, and a thicker RNFL, and in longer eyes toward myopia, a<br />
flatter cornea, and a thinner RNFL8. The possible explaination for this is -<br />
being the smallar eye, nerve fiber layer tends to crowd at the optic disc, hence<br />
leading to increased RNFL thickness.<br />
We have found that there is a change in the RNFL thickness in refractive<br />
errors (axial myopia or hypermetropia) as axial elongation and shortening<br />
will cause spreading and crowding of nerve fiber layer respectively. There<br />
has been no doubt that high refractive errors(≥6 D) cause change in RNFL<br />
thickness but in this study, even in refractive errors of ≤6 D, we have found<br />
statistically significant change in RNFL thickness. So while interpreting OCT<br />
in ocular pathologies these refractive errors should be considered, so that the<br />
RNFL thickness values obtained are due to ocular pathology itself.<br />
REFERENCES<br />
1. Sommer A, Miller NR, Pollack I, Maumenee AE, George T. The Nerve Fiber Layer<br />
diagnosis in glaucoma. Arch Ophthalmol 1977;95:2149-56.<br />
2. Jafe GJ, Caprioli J. OCT to detect and manage various retinal diseases and<br />
glaucoma. Am j Ophthalmol 2004;137:156-69.<br />
3. Dichtl A, Jonas JB, Naumann GO. RNFL thickness in normal eyes. Graefe Arch Clin<br />
Ophthalmol 1999;237:474-9.<br />
4. Ramakrishnan R, Mittal S, Ambatkar S. RNFL thickness measurements in normal<br />
Indian population by OCT. Ind J Ophthalmol 2006;54:11-5.<br />
5. Hoh S, Lim MC, Seah SK. Peripapillary retinal nerve fiber layer thickness variations<br />
with myopia. Ophthalmologica 2006;113:773-7.<br />
6. Schweitzer KD, Ehmann D, Garcia R. RNFL changes in high myopia by OCT. Can<br />
J Ophthalmol 2009;44:13-6.<br />
7. Park SH, Park KH, Kim JM .Relation between Axial length and ocular parameters.<br />
Ophthalmologica 2010;224:188-93.<br />
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69th AIOC Proceedings, Ahmedabad 2011<br />
Family Screening of POAG and PACG Patients:<br />
The Help of Family <strong>Glaucoma</strong> Screening Project<br />
Dr. Devendra Maheshwari, Dr. Neelam Pawar, Dr. Ramakrishnan R,<br />
Dr. Mohideen Abdul Kader, Dr. Ankit Gupta<br />
<strong>Glaucoma</strong> is the second most common cause of blindness wordwide.<br />
Recent estimates showed that there will be approximately 60 million<br />
people affected with primary glaucoma in 2010, rising to 80 million with the<br />
ageing population in 2020 and of these, 74% will have OAG. It is estimated that<br />
4.5 million people will be bilaterally blind from POAG and 3.9 million from<br />
PACG in 2010. Family history is a known important risk factor for developing<br />
glaucoma. 1,2<br />
The Baltimore Eye Survey group reported a higher risk of glaucoma in siblings<br />
than in parents or children of known glaucoma patients. 3 The Barbados Eye<br />
Study Group also reported about four times increase in the risk of glaucoma<br />
in siblings of known glaucoma patients. 4 The prevalence of PACG in the first<br />
degree relatives of whites is estimated to be 1% to 12%. 5 Population-based<br />
studies 6-10 indicate that the incidence of ACG increases with age, is more<br />
common in women, and has a greater prevalence in Asians and East Indians<br />
than in Europeans and Africans. Acute, symptomatic attacks of angle closure<br />
occur in only 20% to 30% of those with angle closure and ACG, 11 with the rest<br />
having an asymptomatic course. Twin studies support a genetic influence in<br />
ACG, 12 but no specific gene has been isolated. As with other diseases, many<br />
genes will eventually be associated with ACG as well as gene/environment<br />
interactions.<br />
However, many studies have relied on patient reporting of family history of<br />
glaucoma. Self reporting is subject to many biases; therefore, it is important to<br />
perform prospective studies on family members of glaucoma patients to assess<br />
the risk of glaucoma development in this population. Moreover, as increasing<br />
age is known to be a risk factor for glaucoma, the number of siblings with a<br />
diagnosis of glaucoma would be expected to increase with time.<br />
MATERIALS AND METHODS<br />
We counselled all the patients of definitive glaucoma to ask their all first<br />
degree relative to come for checkup. We contacted the relatives of glaucoma<br />
patients by means of mailing/telephonic call and did comprehensive ocular<br />
examination to rule out glaucoma after their consent. Consent was obtained<br />
from patients to contact other family members and to participate in the study.<br />
All available family members, affected and normal, were invited to undergo<br />
an ocular examination, visual field testing, and optic nerve head photography.<br />
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Qualified family members were offered an eye examination including, SLE<br />
biomicroscopy, Applanation tonometry, gonioscopy, fundus examination and<br />
pachymetry. Visual field testing was done by use of standard full -threshold<br />
automated static perimetry HFA (24-2 program on the Humphrey Visual Field<br />
Analyzer Zeiss-Humphrey Systems, Dublin, CA) and OCT were also done in<br />
required cases. POAG and PACG were classified as per International society<br />
of Geographical and Epidemiologic Ophthalmic classification [ISGEO]. 16<br />
POAG was classified according to 3 levels of evidence. In category 1, diagnosis<br />
was based on structural and functional evidence. Category 2 was based on<br />
advanced structural damage with unproved field loss. Lastly category 3consist<br />
of persons with an IOP - 99.5th percentile for normal population, whose<br />
optic discs could not be examined because of media opacities Diagnosis of<br />
PACG was as following ; A) primary angle closure suspect [PACS]. ITC in<br />
three or more quadrants, but normal IOP, disc and field,without evidence of<br />
field ; B) primary angle closure [PAC]. ITC in three or more quadrants with<br />
raised and \or IOP primary PAS. Disc and field are normal; C) primary angle<br />
closure glaucoma [PACG]: ITC in three or more quadrants plus evidence of<br />
glaucomatous damage to optic disc and visual field [with similar approaches<br />
as those used for POAG].<br />
RESULTS<br />
We screened 434 relatives of glaucoma patients. Mean age was 61.6yrs ( Range<br />
35-78year); 69.12% subjects were relatives of POAG and 30.8% of PACG. The<br />
mean age in POAG group was 52.6 years (Range 35-67.5 years) and in PACG<br />
group was 67.6 years(Range 35-78 years). 10.45% were diagnosed as definitive<br />
glaucoma. 2% patient were classified as PACG, 8.4% as POAG, 1.1% as POAS,<br />
1.4% as PACS and 0.7% OHT. In POAG 2.2% were severe, 4% as moderate, 2.1%<br />
as mild POAG 35% had advanced PACG.<br />
DISCUSSION<br />
Open-angle glaucoma (OAG) and angle-closure glaucoma (ACG) are the<br />
second leading cause of blindness worldwide. ACG affects 16 million people,<br />
and almost 4 million are bilaterally blind. 1-3 Although three times more people<br />
have OAG than ACG worldwide, the greater morbidity of ACG means that the<br />
absolute number blind is similar to that of OAG. In the developing world, more<br />
than 90% of individuals with glaucoma are undiagnosed and untreated. Even<br />
in developed countries, clinicians presently identify only half of the people<br />
with glaucoma.<br />
Several ocular parameters associated with POAG such as optic disc and cup<br />
size are influenced by heredity. A finish twin cohort study reported a 10.2%<br />
inheritance for POAG. In Baltimore Eye Survey 3 the age- race adjusted odds of<br />
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a positive glaucoma history in glaucoma subjects compared to controls varied<br />
depending on the type of family member affected. The age race adjusted odds<br />
ratio of a positive family history in siblings glaucoma subjects compared to<br />
parents and children of glaucoma subject is greater . In the Barbados Eye<br />
Study, previously undiagnosed subjects were more likely to develop glaucoma<br />
if they had history of glaucoma in one or two more siblings, whereas the<br />
population based family aggregation study in Rotterdam, the life time risk of<br />
glaucoma in siblings and offspring of glaucoma patiients was 9.2 times higher<br />
than in those of controls. Various gene loci were identifiied GLC1A to GLC1F<br />
although six genes have been associated with POAG, the only“ glaucoma<br />
gene” for which a specific protien has been identified is GLC1A .Because<br />
POAG is a heterogenous diseases and some indivisuals exhibit features such<br />
as high IOP or optic disc cupping and others donot, it is likely that even more<br />
gene loci will be identified in POAG families .<br />
There was reliable epidemiologic evidence to suggest that PACG is more<br />
common among Eskimos 6 and Chinese. 7 PACG among Asians was more<br />
frequently chronic and has few symptoms. 8,9<br />
Tornquist 17 found anterior chamber to be genetically determined. He also<br />
reported that the anterior chamber of the fellow eye of persons with uniocular<br />
acute glaucoma is shallower compared to normals. The characteristic shallow<br />
anterior chamber of PACG is caused by abnormal correlation between<br />
structure of the lens and eye ball. 17,18 The crystalline lens continues to grow<br />
throughout life The prevalence of PACG in first degree relatives of which is<br />
estimated to be 1% to 12%. In Eskimos, the prevalence in first degree relatives<br />
has been estimated to be 3.5 times higher than in the general population. In<br />
population based survey in China, the risk of PACG was six times greater in<br />
individuals with a history of glaucoma in any one in the family. 12 However,<br />
studies about genetics of PACG were lacking.<br />
Our data demonstrate that, in families with more than one individual with<br />
POAG and PACG, a large proportion of first-degree and other relatives either<br />
have glaucoma or have an abnormality in one of the three parameters that are<br />
associated with the disease<br />
Family <strong>Glaucoma</strong> screening project developed a novel approach to identify<br />
definitive cases of glaucoma in siblings and those at high-risk for open<br />
angle and closed angle glaucoma. Screening of relatives of glaucoma patients<br />
deserves further study in a more representative selection of the general<br />
population.<br />
REFERENCES<br />
1. Quigley HA, Broman AT.The number of peopil with glaucoma worldwide in 2010<br />
and 2020. Br J Ophthalmol 2006;90;262-7.<br />
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2. Miller SJ.Genetics of glaucoma and family studies. Trans Ophthalmol SocUK<br />
1978;98:290–2.<br />
3. Tielsch JM, Katz J, Sommer A, et al. Family history and risk of primary openangle<br />
glaucoma. The Baltimore Eye Survey. Arch Ophthalmol 1994;112:69–73.<br />
4. Nemesure B, Leske MC, He Q, et al. Analyses of reported family history of<br />
glaucoma: apreliminary investigation. The Barbados Eye Study Group. Ophthalmic<br />
Epidemiol 1996;3:135–41.<br />
5. Congdon N., Wang F., Tielsch J.M.: Issues in the epidemiology and populationbased<br />
screening of primary angle-closure glaucoma. Surv Ophthalmol 1992;36:411.<br />
6. Alsbirk PH. Primary angle-closure glaucoma: oculometry, epidemiology, and<br />
genetics in a high risk population. Acta Ophthalmol. 1976;54:5-31.<br />
7. Foster PJ, Oen FTS, Machin D, et al. The prevalence of glaucoma in Chinese<br />
residents of Singapore. Arch Ophthalmol. 2000;118;1105-11.<br />
8 Dandona L, Dandona R, Mandal P, et al. Angle-closure glaucoma in an<br />
urban population in southern India. The Andhra Pradesh Eye Disease Study.<br />
Ophthalmology 2000;107:1710-6<br />
9. Bonomi L, Marchini G, Marrafa M, et al. Epidemiology of angle-closure glaucoma.<br />
Prevalence, clinical types, and association with peripheral anterior chamber depth<br />
in the Egna-Neumarkt <strong>Glaucoma</strong> Study. Ophthalmology. 2000;107:998-1003.<br />
10. Buhrmann RR, Quigley HA, Barron Y, et al. The prevalence of glaucoma in a rural<br />
east African population. Invest Ophthalmol Vis Sci. 2000;41:40-8.<br />
11. Yip JLY, Foster PJ. Ethnic differences in primary angle-closure glaucoma. Curr<br />
Opin Ophthalmol. 2006;17:175-80.<br />
12. He M, Wang D, Zheng Y, et al. Heritability of anterior chamber depth as an<br />
intermediate phenotype of angle-closure in Chinese: The Guangzhou Twin Eye<br />
Study. Invest Ophthalmol Vis Sci. 2008;49:81-6.<br />
13. Rosenthal AR, Perkins ES. Family studies in glaucoma. Br J Ophthalmol<br />
1985;69:664–7.<br />
14. Becker B, Kolker AE, Roth FD. <strong>Glaucoma</strong> family study. Am J Ophthalmol<br />
1960;50:557– 67.<br />
15. Miller SJH, Paterson GD. Studies on glaucoma relatives. Br J Ophthalmol<br />
1962;46:513–22.<br />
16. Foster PJ, Buhrmann R, Quigley HA, et al. The definition and classification of<br />
glaucoma in prevalence surveys. Br J Ophthalmol 2002;86:238–42.<br />
17. Tornquist R. Shallow anterior Chamber depth in primary acute glaucoma. Br J<br />
Ophthalmol. 1956;40:421-9.<br />
18. Lowe RF. Aetiology of the anatomical basis for pri¬mary angle-closure glaucoma.<br />
Biometrical comparisions be¬tween normal eyes and eyes with primary angleclosure<br />
glaucoma. Br J Ophthalmol. 1970;54:161-9.<br />
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Peripapillary Retinal Nerve Fibre Layer Thickness<br />
in high Myopia: Thinner than the Normal?<br />
Dr. Dipali Rameshchandra Satani, Dr. Surohi Shah, Dr. Amit Patel,<br />
Dr. Shwetambari Singh<br />
To evaluate the relationship between the axial length and refractive error<br />
and peripapillary retinal nerve fibre layer (RNFL) thickness measured<br />
using Stratus optical coherence tomography (OCT) in subjects with high<br />
myopia.<br />
Myopia is the most common ocular abnormality worldwide with prevalence<br />
reported to be 22.7% and 26.2%. One of the potentially blinding ocular<br />
diseases associated with myopia is glaucoma, which is characterized by<br />
progressive degeneration of retinal ganglion cells. An important approach to<br />
detecting preperimetric glaucoma is based on assessment of the retinal nerve<br />
fiber layer (RNFL) thickness. Numerous studies have confirmed that RNFL<br />
measurement is sensitive for detection of glaucoma, and the extent of RNFL<br />
damage correlates with the severity of functional deficit in the visual field.<br />
Although RNFL thinning is indicative of glaucomatous damage, it remains<br />
uncertain whether RNFL thickness would vary with the refractive status of<br />
the eye. It is therefore important to investigate whether any correlation exists<br />
between RNFL measurements and refractive error in myopia, with regard<br />
to the observation that the risk of development of glaucoma is increased<br />
with an increasing degree of myopia. The optical coherence tomographer<br />
(OCT) is a modern imaging device designed to measure the RNFL in a noncontact<br />
and noninvasive manner. With the high axial scanning resolution (10<br />
microns) provided with the OCT, RNFL measurements have been reliable<br />
and reproducible. The purpose of this study is to investigate the relationship<br />
between myopia and RNFL thickness measured by OCT.<br />
MATERIALS AND METHODS<br />
Ours was a prospective comparative observational study in which 80 eyes<br />
of 40 non glaucomatous subjects with spherical equivalent ≥ -6 dioptres (D)<br />
were compared with those of 40 emmetropic controls. All subjects underwent<br />
a full ophthalmic examination including visual acuity, refraction, intraocular<br />
pressure measurement with Goldmann applanation tonometry, dilated<br />
fundus examination with slit lamp biomicroscopy of the optic nerve head,<br />
binocular indirect ophthalmoscopy, refraction, and axial length measurement<br />
with IOL master. OCT was performed with Stratus OCT version 4 model 3000<br />
(Carl Zeiss Meditec Inc.) After pupillary dilation to a minimum diameter of<br />
5 mm, the operator centred the circular scan on the optic nerve head while<br />
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the studied eye was fixated (internal fixation technique). Total average,<br />
quadrantic and mean clock hour RNFL thickness was measured with the<br />
fast RNFL (3.4) scanning protocol (768 A scans in 1.92 seconds). Associations<br />
of RNFL measurements with axial length as well as spherical equivalent<br />
were evaluated by linear regression analysis and expressed as the Pearson<br />
coefficient of correlation (r). P< 0.05 was considered statistically significant.<br />
Statistical analysis was performed with SPSS (version 11.5, SPSS, Chicago).<br />
Other than refractive error, all included eyes had no concurrent disease.<br />
Subjects having evidence of glaucoma (i.e., disc haemorrhage, notching or<br />
thinning of the neural rim), myopic macular degeneration, those who had<br />
undergone intraocular or refractive surgery, those having diabetes or having<br />
an intraocular pressure (IOP) of >21 mm Hg in either eye were excluded.<br />
RESULTS<br />
Mean age of myopes was 28.4 ±10.3 years. Eight subjects had peripapillary<br />
atrophy and 6 had disk tilt. Mean spherical equivalent was -9.48125 ±1.73 D,<br />
with mean axial length of 28.72 ±1.70 mm. In the emmetropic control group,<br />
mean age was 26.9 ± 9.9 years and mean axial length was 23.8 ±0.4 years with<br />
the difference of age distribution between the groups being statistically<br />
insignificant by unpaired t test (P= 0.508). There was significant difference<br />
between axial length (P
69th AIOC Proceedings, Ahmedabad 2011<br />
myopia. In myopic eyes, the elongation of the globe leads to mechanical<br />
stretching and thinning of the retina. Therefore, it is conceivable that the<br />
extent of the elongation would be related to the degree of retinal thinning,<br />
although it is yet to be ascertained whether the RNFL thickness is decreased<br />
at the histologic level.<br />
The principal analysis performed by OCT is the comparison of the measured<br />
RNFL thickness of each sector (clock hour or quadrant) to the normative<br />
database of the respective sector and may lead to a high false-positive rate in<br />
glaucoma diagnosis.<br />
The default axial length in every OCT scan is 24.46 mm, and the scanning<br />
radius for the fast/standard RNFL scanning protocol is fixed at 1.7 mm.<br />
Therefore, the actual scanning radius in a myopic eye could be longer than<br />
1.7 mm due to the magnification effect. However, the optic disc size may also<br />
increase with myopia, it does not necessarily mean that the RNFL is being<br />
measured farther from the disc margin.<br />
It has been suggested that the shape of RNFL thickness plot in a high myopic<br />
is similar to that found in the normal database, with a “double hump.” Thus,<br />
visual or mathematical shape analysis of the RNFL thickness profile may be<br />
of assistance in differentiating those high myopes with glaucoma from those<br />
without.<br />
The increased risk of development of glaucomatous change may be related<br />
to the already reduced RNFL thickness in myopic eyes. On the other hand,<br />
the reduced RNFL thickness in myopia may itself represent a risk factor for<br />
development of glaucoma. Further studies with longitudinal follow-up would<br />
be useful to address this question fully.<br />
Spectral domain OCT; a newer version is now available which has much<br />
higher resolution i.e., 6 to 8 µm. A limitation of our study is the relatively<br />
small number of subjects. In addition, we did not exclude subjects with PPA<br />
extended to area where OCT samples. Inclusion of these subjects could have<br />
introduced potential selection bias.<br />
RNFL measurements vary with the axial length/refractive error of the eye.<br />
Although the normative database provided by OCT has been helpful in<br />
identifying ocular diseases involving the RNFL, it may not be reliable in the<br />
analysis of myopic eyes.<br />
High myopic subjects tend to have thin peripapillary RNFL as measured<br />
by Stratus OCT. This phenomenon should be considered when interpreting<br />
a glaucoma suspect’s RNFL measurements. Stratified normal databases are<br />
required for accurate diagnosis of conditions resulting in nerve fibre loss such<br />
as chronic glaucoma.<br />
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REFERENCES<br />
1. Effect of myopia on the thickness of the retinal nerve fiber layer measured by<br />
Cirrus HD optical coherence tomography. Kang SH et al. Invest Ophthalmol Vis Sci.<br />
2010;51:4075-83.<br />
2. Myopia affects retinal nerve fiber layer measurements as determined by optical<br />
coherence tomography. Rauscher FM et al. J <strong>Glaucoma</strong> 2009;18:501-5.<br />
3. Peripapillary retinal nerve fibre layer thickness profile in subjects with myopia<br />
measured using the Stratus optical coherence tomography. Kim MJ et al. Br J<br />
Ophthalmol. 2010;94:115-20.<br />
4. Nerve fibre layer changes in highly myopic eyes by optical coherence tomography.<br />
Schweitzer KD et al. Can J Ophthalmol. 2009;44:e13-6.<br />
5. Retinal nerve fiber layer measurements in myopia: An optical coherence<br />
tomography study. Leung CK et al. Invest Ophthalmol Vis Sci. 2006;47:5171-6.<br />
6. The effect of myopia on retinal nerve fibre layer measurement: a comparative study<br />
of spectral-domain optical coherence tomography and scanning laser polarimetry.<br />
Wang G et al. Br J Ophthalmol. 2010;27.<br />
7. Comparing the ganglion cell complex and retinal nerve fibre layer measurements<br />
by Fourier domain OCT to detect glaucoma in high myopia. Kim NR et al. Br J<br />
Ophthalmol. 2010;30.<br />
Inter-Observer Variation for Non-Simultaneous<br />
Stereo Disc Photo Pairs with A Regular Fundus<br />
Camera<br />
Dr. Sushma Tejwani, Dr. Jyoti Matalia, Dr. Bhujang Shetty K<br />
Disc photographs with the stereo systems are considered to be the gold<br />
standard for sequential optic disc examination for glaucoma, but most of<br />
these systems are expensive. A regular fundus camera with manual separation<br />
can offer the same effect and therefore of more practical use especially in<br />
developing countries. However the technique used to take stereo pictures<br />
with a regular camera has not been standardized. The purpose of this study<br />
is to validate the disc measurement taken using the above technique by two<br />
glaucoma specialists.<br />
To study inter-observer variation for evaluating disc photographs obtained<br />
with the regular fundus camera with the manual separation. Tertiary eye care<br />
center in southern India.<br />
MATERIALS AND METHODS<br />
It was a retrospective cohort study wherein disc photographs of patients seen in<br />
the glaucoma clinic between July 2008 to April 2009 were analyzed. Each optic<br />
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disc was photographed with a digital Topcon fundus camera with 20 degrees<br />
field settings and manual lateral movement to obtain non-simultaneous<br />
stereo pairs. Two ophthalmologists separately scored the photographs for the<br />
following parameters:<br />
1) Comparison of vertical Cup/Disc (C/D) ratio;<br />
2) Deviation from ISNT rule;<br />
3) Presence or absence of glaucoma;<br />
4) Thinnest neuroretinal rim (NRR).<br />
Interobserver variability was calculated with Intraclass correlation (ICC) for<br />
continuous variables like C: D ratio and with Kappa coefficient of agreement<br />
for the non- continuous variables like deviation from ISNT rule, presence or<br />
absence of glaucoma and thinnest NRR. Both the statistical tests were done<br />
using MedCalc software.<br />
RESULTS<br />
Two glaucoma specialists independently rated 170 discs of 109 patients.<br />
1. Intraclass Correlation Coefficient calculated for C/D ratio was<br />
ICC<br />
95% confidence interval<br />
Single measure 0.9495 0.9323-0.9624<br />
Average measure 0.9741 0.9649-0.9809<br />
2. Kappa coefficient for inter-rater variability for deviation from ISNT rule,<br />
was found to be 0.87 with the 95% CI: 0.796 to 0.944;<br />
3. Kappa coefficient for differentiating glaucoma from normal, was 0.774<br />
with 95% CI: 0.679 to 0.870;<br />
4. Kappa coefficient for thinnest NRR was 0.831; 95% CI: 0.743 to 0.919.<br />
• Value of kappa<br />
– < 0.20 – Poor<br />
– 0.21- 0.4 – fair<br />
– 0.41- 0.6 – Moderate<br />
– 0.61-0.80 – Good<br />
– 0.81- 1.00 – Very good<br />
• Kappa values for this study show that agreement between the two<br />
observers was<br />
– Very good for C:D ratio, ISNT rule and thinnest NRR<br />
– Good for the forth parameter of differentiating normal from glaucoma<br />
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DISCUSSION<br />
This technique is an inexpensive tool for differentiating normal from glaucoma<br />
and for sequential disc evaluation. A good correlation and agreement was<br />
achieved between the observers. This technique is an inexpensive and a useful<br />
tool in developing countries as a method of differentiating a normal disc from<br />
glaucomatous discs and in sequential disc evaluation during follow-up of<br />
glaucoma.<br />
Dr. S SUJATA: MBBS (1990), Lady Hardinge Medical College, New Delhi,<br />
Delhi University, MD (1994), Dr. Rajendra Prasad Center for Ophthalmic<br />
Sciences, A<strong>II</strong>MS, New Delhi. Presently, Prof & HOD, <strong>Glaucoma</strong> Services,<br />
Institute of Ophthalmology Joseph eye Hospital, Trichy, Tamil Nadu.<br />
E-mail: sujatasubbiah2@gmail.com<br />
Role of Intravitreal Avastin in Neovascular<br />
<strong>Glaucoma</strong><br />
Dr. S Sujata, Dr. A Prabhakaran, Dr. C A Nelson Jesudasan<br />
Neovascular glaucoma (NVG) is a form of secondary glaucoma in which<br />
abnormal fibrovascular tissue grows on the iris and drainage angle<br />
structures including trabecular meshwork. Contraction of this tissue leads to<br />
progressive angle closure and intraocular pressure elevation (IOP) leading to<br />
glaucoma that is poorly responsive to conventional treatment and poor visual<br />
prognosis1. Retinal ischemia and vascular endothelial growth factor type A<br />
(VEGF-A) have been implicated as major angiogenic stimuli responsible for<br />
retinal neovascularization. Inhibition of this mediator seems to have a strong<br />
biologic basis for treatment of NVG1.<br />
To report efficacy of intravitreal Avastin (Bivacizumab) in regression of NVI<br />
and IOP control in NVG.<br />
MATERIALS AND METHODS<br />
A prospective, interventional, non comparative clinical trial was conducted at<br />
a tertiary eye care center. Thirty consecutive patients with NVG were screened<br />
and evaluated for eligibility.<br />
Inclusion criteria: clinical diagnosis of neovascular glaucoma by slit lamp<br />
with evidence of neovascularization of iris/ and angle and elevated IOP not<br />
controlled by maximum medical therapy with presence of underlying cause<br />
for retinal ischemia i.e. CRVO, vitreous hemorrhage, advanced PDR, patient<br />
willing for intravitreal Bevacizumab (IVB) with no systemic contraindication<br />
for IVB.<br />
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Exclusion criteria were; monocular patients, BCVA better than 20/200, systemic<br />
contraindication for intravitreal injection, medically controlled NVG, patient<br />
lost to follow up or NVG due to intraocular tumor and anterior segment<br />
pathology interfering with IOP measurement i.e. ptreygium.<br />
All patients underwent a complete clinical and ophthalmic examination<br />
including BCVA, slit lamp bio-microscopic examination, IOP measurement<br />
using Goldmann applanation tonometer, gonioscopic examination. Fundus<br />
fluorescein angiography and fundus examination was done to evaluate pre<br />
existing cause for ischemic retinal disorder. B-scan ultrasonography in hazy<br />
media. Preoperative pan retinal photocoagulation (PRP) and postoperative<br />
PRP was given wherever necessary. Systemic examination was done by an<br />
internist and fitness for intravitreal injection obtained.<br />
Under topical anesthesia, in the infero-temporal quadrant, 4mm from the<br />
limbus 50µl of Bevacizumab (1.25 mg) was injected intravitreally via pars<br />
plana under visualization wherever possible. Postoperatively steroids and<br />
antiglaucoma medications were given.<br />
Postoperative follow up examinations were performed on 3rd day, 1st week,<br />
1st month, 3 months, 6 months after the IVB. In each follow up BCVA, slit lamp<br />
examination, IOP measurement, gonioscopy for regression or recurance of<br />
NVI, NVA and need of additional or withdrawal of antiglaucoma medication<br />
were noted.<br />
Repeat injection of IVB was performed in patients if there is no regression<br />
or reappearance of NVI with increase in pain and symptoms despite, IVB,<br />
additional PRP and maximum tolerable anti-glaucoma topical medications.<br />
Statistical analysis was performed using SPSS (version 10.0) p value ≤ 0.05 was<br />
considered statistically significant.<br />
RESULTS<br />
Thirty eyes of 30 patients were enrolled in the study, 22(73.3%) were males<br />
and 8(26.6%) were females with mean age 65.53 ± 8.57yrs (range, 52-78 yrs).<br />
Mean follow up period was 12.4 ± 3.52 months (range, 6 -18 months). Of these<br />
14 eyes had NVG with open angles and 16 had NVG with angle closure. In 22<br />
patients, CRVO (73.33%), 4 eyes CRVO with PDR (13.3%), posterior uveitis in 2<br />
eyes (6.67%), and PDR alone was the underlying cause for neovascularization<br />
in 2 eyes (6.67%). All patients had medical treatment for IOP reduction prior to<br />
treatment with IVB.<br />
The mean IOP at the time of presentation in 30 eyes was 52.13 ± 12.93 mm Hg<br />
(range, 28 - 72) and mean IOP before IVB with medical management was 36.13<br />
± 11.92 mm Hg (range, 16 – 56).The mean IOP at 1st visit after IVB was 34.8 ±<br />
12.23 mm Hg (range, 16 – 64) and mean IOP at the end of follow-up, post IVB<br />
with medical management was 37.20 ± 21.30 mm Hg.<br />
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Table 1: Mean change in IOP at different follow-up intervals<br />
IOP Change Mean Values P Value<br />
IOP at presentation to IOP before IVB 16.00 ± 12.26 0.00<br />
IOP at presentation to IOP after IVB 1st visit 17.33 ± 11.07 0.00<br />
IOP at presentation to IOP at end of followup 14.93 ± 20.04 0.012<br />
IOP before IVB to IOP after IVB 1st visit 1.33 ± 13.51 0.708<br />
IOP before IVB to IOP at final followup -1.06 ± 18.32 0.825<br />
IOP after IVB 1st visit to end of followup -2.40 ± 14.18 0.523<br />
The mean reduction in IOP from the time of presentation to that before IVB<br />
was 16.00 ± 12.26 mm Hg. (p=0.000).The mean reduction in IOP at first followup<br />
(after IVB) to that at presentation was 17.33 ± 11.07 mm Hg (p=0.000).The mean<br />
reduction in IOP from the time of presentation to that at final follow-up (after<br />
IVB) was 14.93 ± 20.04 mm Hg (p=0.012).<br />
The mean reduction in IOP at first follow up after IVB was 1.33 ± 13.51 mm Hg.<br />
(p=0.708). At first followup 2 eyes (6.67%) had raised IOP. At final follow up<br />
10 eyes (33.33%) had persistently raised IOP. Twenty six eyes (86.6%) showed<br />
significant regression of NVI. PRP was done in 14 eyes before IVB, 18 eyes<br />
after IVB and of these 6 eyes had received PRP before and after IVB. Four eyes<br />
needed repeat IVB. Six eyes underwent trabeculectomy with cataract surgery<br />
and 2 eyes needed cyclocryotherapy. Subjective reduction in pain was noted in<br />
28 eyes (93.3%). Visual acuity improvement was seen in 4 eyes (13.3%).<br />
DISCUSSION<br />
Bevacizumab (Avastin) is a humanized murine antibody that binds all<br />
isoforms of VEGF-A. Intravitreal injection of this agent bypasses the blood<br />
ocular barrier and provides high local concentration without exposing patient<br />
to systemic side effects. 1 Yazdani etal report reduction of NVI and IOP in NVG<br />
and suggest it as an adjunct in the management of NVG1. Multiple case reports<br />
have shown IVB causes regression of NVI when injected intravitreally often<br />
within 1 week, duration is short-lived lasting about 4-10 weeks with no ocular<br />
or systemic side effects.<br />
In our study, CRVO was the underlying cause for NVG in 22 eyes (73.3%) similar<br />
to that reported by Iliev et al. 2 Twenty eyes (66.66%) showed IOP reduction, 26<br />
eyes (86.6%) showed significant reduction in NVI similar to that reported by<br />
Wakabayashi 3 etal. Visual acuity improvement was seen in 4 eyes (13.3%) and<br />
subjective reduction in pain in 28 eyes (93.3%) similar to that in a study by Iliev<br />
et al. 2 None of our patients had any local or systemic side effects.<br />
Use of IVB in NVG facilitates regression and resolution of anterior segment<br />
neovascularization, stabilization of IOP, relief of pain and discomfort without<br />
any side effects thus demonstrating the potential for IVB as an adjunctive<br />
treatment option for NVG.<br />
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REFERENCES<br />
1. Yazdani S, Hendi K, Pakravan M, Mahadavi M, Yaseri M.Intravitreal Bevacizumab<br />
for neovascular glaucoma. A randomized controlled trial. J. Glaucom 2008;18:632-7.<br />
2. Iliev ME, Domig D, Wolf-Schnurrbursch U, Wolf S, Sarra G.Intravitreal Bevacizumab<br />
in the treatment of neovascular glaucoma. Am J Ophthalmol 2006;142:1054-6.<br />
3. Wakabayashi T, Oshima Y, Sakaguchi H, Ikuno Y, Miki A etal.Intravitreal<br />
Bevacizumab to treat iris neovascularization and neovascular glaucoma<br />
secondary to ischemic retinal diseases in 41 consecutive cases. Ophthalmology<br />
2008;115:1571-80.<br />
Evaluation of Quality of Life in Elderly POAG<br />
Patients by Using the GQL-15 Questionnaire<br />
Dr. Devendra Maheshwari, Dr. Neelam Pawar, Dr. R Ramakrishnan,<br />
Dr. Mohideen Abdul Kader, Dr Ankit Gupta<br />
<strong>Glaucoma</strong> affects daily life both through visual deterioration and by the<br />
glaucoma treatment itself and the evaluation of glaucomatous patients’<br />
disabilities is a difficult task. Because glaucoma is the third most common<br />
cause of blindness in the world and has been projected to become the most<br />
common cause of blindness in the first years of this millennium, it is important<br />
to know the quality of life of these patients. 1,2 <strong>Glaucoma</strong> patients can lose<br />
quality of life (QoL) for several reasons: the diagnosis itself, the functional<br />
loss, the inconvenience of the treatment, the side effects of the treatment and<br />
the cost of the treatment. several studies have demonstrated that even patients<br />
in the early stages of progressive glaucoma experience deficits in glaucomarelated<br />
QoL (G-QoL) associated with self-perceived visual dysfunction. 7–9<br />
Among the available generic and vision-specific instruments employed in<br />
studies, popular QoL measures have included the Short Form-36 (SF-36) or<br />
Short Form-12 (SF-12) 5,8,10,11 the 25- item National Eye Institute Visual Function<br />
Questionnaire (NEI VFQ-25) 3,10,12 the Visual Activities Questionnaire (VAQ) 9,13<br />
the Activities of Daily Vision Scale 14,15 and the Visual Function Index (VF-<br />
14). 11 Our objective was to measure G-QoL in patients with glaucoma and to<br />
ascertain the strength of correlation between self-reported visual disability<br />
and objective measures of visual function.<br />
MATERIALS AND METHODS<br />
Men and women with glaucoma who attended clinic, Jan 2009 to Jan 2010<br />
were eligible for inclusion. During the same period, control participants, who<br />
had no family or personal history of glaucoma, were recruited from relatives<br />
and friends of the investigators and of patients who attended the practice. All<br />
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eligible participants had to be at least 18 years old and be able to speak and<br />
read English fluently. Patients with any nonglaucomatous condition or disease<br />
affecting visual function, such as cataract, diabetes, macular degeneration, or<br />
stroke were excluded. Eligible subjects were prospectively approached during<br />
regularly scheduled follow-up visits; those giving consent were enrolled<br />
consecutively. Participants with open-angle glaucoma had an established<br />
diagnosis in one or both eyes given by the same glaucoma subspecialist<br />
ophthalmologist Open-angle glaucoma was diagnosed on the basis of<br />
characteristic optic disc changes with or without raised intraocular pressure<br />
or glaucomatous visual field loss demonstrated on the Humphrey Visual Field<br />
Analyzer (HFA).<br />
Data Collection Before the completion of GQL-15 questionnaires, all subjects<br />
were interviewed face-to-face and provided demographic information.<br />
Snellen visual acuity (VA) was recorded and converted to logarithm of the<br />
minimum angle of resolution (logMAR) for analysis. Achromatic perimetry<br />
was performed using the HFA SITA 24-2. For the purpose of analyses, subjects<br />
were stratified by glaucoma severity using the glaucoma staging system (GSS)<br />
developed by Nelson and colleagues,1 wherein the central visual fields were<br />
classified in to 3 groups: ‘‘mild’’ (unilateral loss with less than half of visual<br />
field lost), ‘‘moderate’’ (unilateral loss with more than half of the visual field<br />
lost or bilateral loss with less than half of the visual field lost in each eye), or<br />
‘‘severe’’ (bilateral loss with more than half of the visual field lost in either eye).<br />
This GSS has been shown to correlate strongly with perimetric mean deviation<br />
(MD). In addition, a secondary analysis using the Bascom Palmer GSS criteria<br />
for perimetric MD was performed to confirm the correlation between GQL-15<br />
score and disease severity.<br />
In this criteria, the stages of glaucoma and corresponding HFA MD<br />
measurements, reported in units of decibels (dB) are as follows: stage 0 (earliest<br />
glaucoma): >0.00, stage 1 (early glaucoma): _0.01 to _6.00; stage 2 (moderate<br />
glaucoma): _6.01 to _12.00, stage 3 (advanced glaucoma): _12.01 to _20.00, stage<br />
4 (severe glaucoma): _20.01 or worse, and Stage 5 (blindness): no Humphrey<br />
visual field in worse eye. 13 The GQL-15 questionnaire is composed of 15<br />
items,which addresses 4 factors of visual disability: (1) central and near vision;<br />
(2) peripheral vision; (3) dark adaptation and glare; and (4) outdoor mobility.<br />
For the GQL-15 summary scores, item-level responses for each factor were<br />
coded on a scale of 0 to 5, wherein 0 signified abstinence from activity owing<br />
to nonvisual reasons, 1 indicated no difficulty, and 5 represented severe<br />
difficulty. Summary scores represented the sum of item-level response scores<br />
with higher scores indicating poorer G-QoL. For subscale scores, the item<br />
level responses were scored on a numerical interval scale ranging from 0,<br />
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indicating no difficulty, to 100, indicating severe difficulty. Subscale scores<br />
were calculated for each factor by averaging the sum of scores generated for<br />
the item-level responses. Higher subscale scores represented more difficulty<br />
with vision-related activities and poorer G-QoL. For the purpose of statistical<br />
analysis, self perceived visual dysfunction was defined as having a subscale<br />
score greater than 0 in any one or more of the 4 factors of visual disability.<br />
RESULTS<br />
75 patients with glaucoma and 25 subjects without glaucoma meeting the<br />
eligibility criteria were enrolled. The mean age of the patients with glaucoma<br />
was 71 [standard deviation (SD)8.1; range, 43 to 86] versus 62 years (SD 7.9; range,<br />
46 to 84) for controls. Overall, patients with glaucoma and control subjects<br />
differed significantly with respect to age, disease presence, VA, and perimetric<br />
visual field indices. Stratification by disease severity showed that compared<br />
with controls, patients with mild, moderate, and severe glaucoma experienced<br />
significant reductions in VA and greater visual field loss, evidenced by higher<br />
mean HFA pattern standard deviation and lower HFA MD measurements (all<br />
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patients with early glaucoma. For activities requiring central and near vision,<br />
peripheral vision, and outdoor mobility, the differences between patients with<br />
mild glaucoma and the control subjects were more pronounced and reached<br />
a level of statistical significance. On the other hand, patients with severe<br />
glaucoma were relatively less encumbered by activities involving central and<br />
near vision or peripheral vision, but felt disabled by those involving outdoor<br />
mobility.<br />
Overall, these outcomes suggest that certain functional problems become<br />
less pronounced as the disease progresses; perhaps patients adapt to their<br />
decreasing vision over time, accept their reduced level of visual function, or<br />
use aids or other strategies to overcome their visual disability. To date, many<br />
of the published studies evaluating the impact of glaucoma on G-QoL have<br />
used a variety of general and vision-related instruments and also focusing on<br />
nonspecific outcomes such as VA.<br />
Nelson and colleagues 7 adopted a novel approach by introducing the concept<br />
of a glaucoma-specific questionnaire in a pilot study and followed that up with<br />
a validation of a shorter GQL-15. 1 Both studies demonstrated that problems<br />
encountered by patients with glaucoma in everyday life were reflected in<br />
their performance on the GQL and GQL-15 respectively, and also on a number<br />
of psychophysical tests such as the Pelli-Robson contrast sensitivity test,<br />
glare disability, Esterman binocular visual field test, dark adaptation, and<br />
stereopsis. 1,7<br />
However, unlike Nelson et al 1 who observed a marked difference in GQL-<br />
15 summary performance measures between patients with mild and severe<br />
glaucoma only, the differences among patients in all stages of glaucoma in our<br />
study were statistically significant. Health-related QoL is multidimensional,<br />
the ophthalmologist must also consider other factors not included in our<br />
study, such as visual and nonvisual side effects of treatment, noncompliance/<br />
compliance, general health issues, and the patient’s fears and psychosocial<br />
wellbeing, when evaluating vision-specific and global QoL. However, given<br />
its simplicity, brevity, and strong, significant relationship with a measure of<br />
visual field loss, we believe that the GQL-15 is a useful assessment tool that<br />
may be implemented by the ophthalmologist in the management of patients<br />
with glaucoma.<br />
REFERENCES<br />
1. Foster A, Johnson GJ. Magnitude and cause of blindness in the developing world.<br />
Int Ophthalmol 1999; 14:135-40.<br />
2. Day DG, Sharpe ED, Atkinson MJ, et al. The clinical validity of the treatment<br />
satisfaction survey for intraocular pressure in ocular hypertensive and glaucoma<br />
patients. Eye 2006;20:583–90.<br />
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3. Hyman LG, Kamaroff E, Heijl A, et al. Treatment and visionrelated quality of life<br />
in the Early Manifest <strong>Glaucoma</strong> Trial. Ophthalmology 2005;112:1505–13.<br />
4. Nesher R, Ticho U. Switching from systemic to the topical carbonic anhydrase<br />
inhibitor dorzolamide; effect on the quality of life of glaucoma patients with drugrelated<br />
side effects. IsrMed Assoc J. 2003;5:260–3.<br />
5. Javitt JD, Schiffman RM, Brimonidine Outcomes Study Group I. Clinical success<br />
and quality of life with brimonidine 0.2% or timolol 0.5% used twice daily in<br />
glaucoma or ocular hypertension: a randomized clinical trial. J <strong>Glaucoma</strong>. 2000;9:<br />
224–34.<br />
6. Stein JD. Disparities between ophthalmologists and their patients in estimating<br />
quality of life. Curr Opin Ophthalmology. 2004;15:238–43.<br />
7. Nelson P, Aspinall P, O’Brien C. Patients’ perception of visual impairment in<br />
glaucoma: a pilot study. Br J Ophthalmol 1999;83:546–52.<br />
8. Iester M, Zingirian M. Quality of life in patients with early, moderate and advanced<br />
glaucoma. Eye 2002;16:44–9.<br />
9. Janz NK, Wren PA, Lichter PR, et al. The CIGTS Group. Quality of life in newly<br />
diagnosed glaucoma patients. Ophthalmology 2001;108:887–98.<br />
10. Jampel HD, Schwartz A, Pollack I, et al. <strong>Glaucoma</strong> patients’ assessment of their<br />
visual function and quality of life. J <strong>Glaucoma</strong>. 2002;11:154–163.11. Nah YS, Seong<br />
GJ, Kim CY. Visual function and quality of life in Korean patients with glaucoma.<br />
Korean J Ophthalmol. 2002;16:70–4.<br />
12. Mangione CM, Lee PP, Gutierrez PR, et al. The National Eye Institute Visual<br />
Function Questionnaire Field Test Investigators. Development of the 25-item<br />
National Eye Visual Function Questionnaire. Arch Ophthalmol. 2001;119:1050–8.<br />
13. Mills RP, Janz NK, Wren PA, et al. Correlation of visual field with quality-of-life<br />
measures of diagnosis in the Collaborative Initial <strong>Glaucoma</strong> Treatment Study<br />
(CIGTS). J <strong>Glaucoma</strong>. 2001;10:192–8.<br />
Association of MTHFR 677C>T Polymorphism with<br />
Primary Open Angle <strong>Glaucoma</strong> in North Indian<br />
Population<br />
Dr. Abhishek Chandra, Dr. Abhishek Dixit, Dr. Ritu Barnwal, Dr. Om<br />
Prakash Singh Maurya, Dr. Mousumi Mutsuddi, Dr. Akhtar Ali<br />
<strong>Glaucoma</strong> is a heterogeneous group of disease that have in common a<br />
characteristic optic neuropathy and associated visual field loss for which<br />
elevated IOP (Intra-ocular-pressure) is one of primary risk factors. The most<br />
common type of glaucoma includes primary Open Angle <strong>Glaucoma</strong> (POAG)<br />
and Primary Closed Angle <strong>Glaucoma</strong> (PCAG). Many genetic and non genetic<br />
factors have been associated with POAG. An increased level of plasma<br />
homocysteine has been observed in patients with glaucoma. 1 Homocysteine<br />
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concentration has been found to be affected by a single base pair mutation<br />
C677T (results in a missense mutation leading to the substitution of valine for<br />
alanine at position 222 of MTHFR enzyme, causing the synthesis of a thermo<br />
labile enzyme with a 50% reduction in activity 2 and A1298C in MTHFR gene.<br />
Double heterozygosity for MTHFR 677C>T and 1298A>C polymorphisms<br />
results in lower MTHFR activity as compared to heterozygosity for either<br />
MTHFR variant separately. 8 MTHFR gene is an important gene of 20.329<br />
kb in length, encoding for a 656 amino acid long polypeptide, Methlylene<br />
Tetra Hydro Folate Reductase which acts as an important enzyme for<br />
homocysteine(Hcy) metabolism. 5 MTHFR catalyzes the conversion of 5,<br />
10-methyltetrahydrofolate to 5-methyltetrahydrofolate, which is required for<br />
remethylation of homocysteine to methionine.<br />
Mutation in MTHFR may lead to reduced activity of Methylene Tetra Hydro<br />
Folate Reductase enzyme which ultimately leads to the accumulation of Hcy<br />
in blood. Accumulated Hcy has many implications like neuronal cell death by<br />
different apoptotic and excitotoxic mechanism 3 , apoptotic cell death in Retinal<br />
Ganglion Cells (RGC) by overstimulation of NMDA receptors and caspase-3<br />
activation 4 , vascular injuries, alteration in extracellular matrix, structural<br />
remodeling of connective tissue. The prevalence of this polymorphism varies<br />
in different ethnic population and also among different types of glaucoma.<br />
Association of any of the MTHFR gene polymorphism with Primary Open<br />
Angle <strong>Glaucoma</strong> has not yet been studied in Indian population. Although<br />
some evidences are present for association studies on Caucasian population<br />
and Pakistani cohorts.<br />
The present study was designed to investigate the role of the MTHFR 677C>T<br />
polymorphism in patients with POAG.<br />
MATERIALS AND METHODS<br />
Patient selection criteria:<br />
In this case-controls study a total of 39 patients with POAG and 39 controls<br />
have been investigated at Department of Ophthalmology of Institute of<br />
Medical Science, Banaras Hindu University, Varanasi.<br />
a. Inclusion criteria:<br />
1. An IOP before initiation of a pressure lowering therapy of at least 21 mm<br />
Hg.<br />
2. An open anterior chamber angle (Grade 3 and above by Shaffer’s<br />
Classification).<br />
3. Optic disc changes characteristic for glaucoma (notching, thinning of<br />
Neuro Retinal Rim, increased C D ratio) with a C:D ratio of ≥ 0.8 in at<br />
least one eye.<br />
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b. Exclusion criteria:<br />
1. Age< 30<br />
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2. Other ocular disoders like uveitis, etc.<br />
3. Other forms of glaucoma like pigmentary glaucoma, pseudo-exfoliation<br />
syndrome etc.<br />
Control subjects consisted of 39 unrelated subjects with no morphological<br />
or functional damage indicative of Primary or Secondary Open Angle<br />
<strong>Glaucoma</strong>. Medical history concerning arterial hypertension, diabetes<br />
mellitus, cardiovascular events and recent medication was obtained from<br />
all patients. All participants were from same geographical area (Eastern U.P.<br />
and Bihar). Informed consent was taken from glaucoma patients and control.<br />
All patients were thoroughly examined using slit lamp bimicroscopy using<br />
78D or 90 D lenses. Intra Ocular Pressure (IOP) was measured by Goldman<br />
applanation tonometer; angle structures were assessed and graded by using<br />
Goldman single mirror gonioscope and visual field examination (automated<br />
perimetry by Humphrey field analyser) was done in patients wherever<br />
possible. Peripheral blood samples (3-5 ml) of patients and controls were<br />
received in heparinized syringe from Department of Ophthalmology. Samples<br />
were immediately stored at 4°C until the extraction of genomic DNA. Genomic<br />
DNA was extracted by standard ethanol precipitation method and stored at<br />
-20°C until further processing.<br />
Polymerase Chain Reaction- Restriction Fragment length<br />
Polymorphism<br />
Detection of C677T MTHFR polymorphism was performed by polymerase<br />
chain reaction (PCR) followed by HinfI restriction enzyme digestion. Briefly,<br />
we used the forward primer 5′TGAAGG AGAAGGTGTCTGCGGGA 3′ and the<br />
reverse primer 5’CCTCACCTGGATGGGAAAGAT CC3′ (6) to amplify 146 base<br />
pair fragment of the MTHFR gene. Each 25 μl PCR reaction contained 2.5 μl of<br />
10X reaction buffer, 1.5 mmol MgCl2, and 1μl from 10 pmol of each primer, 1.25<br />
mmol of the deoxynucleoside triphosphates, 0.5 U of Taq DNA polymerase<br />
(Fermentas), and 100 ng of genomic DNA template. PCR was carried out at pre<br />
standardized conditions: Initial denaturation at 94 °C for 5 min, and 94°C for 1<br />
min, followed by annealing at 62 °C for 1min, and then extension at 72 °C for 1<br />
min, repeated for 35 cycles followed by a final extension step at 72 °C for 3 min.<br />
The PCR products were electrophoresed on 2% agarose gel to confirm the<br />
correct amplicon size. After run, the gel was visualized in Gel DOCTM XR+<br />
Imaging system of BIO-RAD. Restriction enzyme digestion was performed on<br />
PCR products using the HinfI restriction enzyme (Fermentas). The restriction<br />
digestion was carried out in a 25 μl reaction on 20μl of PCR product using Hinf<br />
I enzyme (0.2 U). The digestion mixture was incubated overnight at 37°C. After
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digestion, all fragments were resolved on 3.5% agarose gel. A single fragment<br />
of 146 base pairs (bp) was identified as homozygous (CC); three fragments of<br />
146, 124, and 22 bp were identified as heterozygous (CT); and two fragments of<br />
124 and 22 bp were identified as homozygous (TT) genotype. The 22 bp band<br />
is too short to be visualized by Agarose gel electrophoresis.<br />
RESULTS<br />
The demographic data like no. of patients mean age, male: female ratio is<br />
shown in table 1. The table 2 presents genotype distribution and frequency of<br />
the MTHFR C677T allele in patients with POAG and control subjects.<br />
Table 1: Demographic data of POAG cases and controls<br />
Patients with Poag<br />
Control Subjects<br />
No of patients 39 39<br />
Age<br />
Mean±SD 49.625±17.419 56.825±13.326<br />
Range 22-80 30-80<br />
Gender (Male: Female) 1.05:1 1:1.05<br />
Table 2: AMTHFR C677T genotype distribution in POAG cases and<br />
controls<br />
Genotype Cases Controls<br />
N=39 N=39<br />
677 CC 18(46.15%) 27(69.23%)<br />
677 CT 20(51.28%) 11(28.21%)<br />
677TT 01(2.564%) 01(2.564%)<br />
Chi sq= 4.413 ------<br />
(df= 2)<br />
P value= 0.11 ------<br />
CT VS CC<br />
OR= 2.73 ------<br />
95% CI= (1.06-7.03)<br />
An association was hence found in this North Indian population as cases were<br />
more associated with 677 CT than controls (p value=0.11, χ2=4.413). Although<br />
there is a difference in the frequency of distribution of genotype but this is<br />
not statistically significant and may arise by chance. This small difference in<br />
p value is due to small sample size. Measurement of homocysteine level in<br />
patient would have given some satisfactory results in this retrospective study.<br />
DISCUSSION<br />
The frequency of CT genotype is 81.8% more in cases as compared to controls<br />
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although statistically insignificant (p= 0.11) probably due to low sample size.<br />
Thus MTHFR gene appears to be an association in Indian patients with POAG.<br />
Therefore this study needs to be performed on a larger sample size to validate<br />
this association.<br />
Factors Affecting Compliance in <strong>Glaucoma</strong><br />
Therapy in Eastern Indian Population<br />
Dr. Prasanta Kumar Nanda, Dr. Sumita Mohapatra<br />
<strong>Glaucoma</strong> is a chronic condition requiring, in majority of cases, lifelong<br />
topical therapy. Non-compliance with prescribed treatment has proven<br />
to be a significant obstacle to the effective glaucoma management. Lack of<br />
compliance may be confused with a therapy’s lack of efficacy, and could lead<br />
to more aggressive therapy or unnecessary surgery. Since glaucoma produces<br />
mild or no symptoms early on, and treatment is designed to prevent worsening<br />
rather than to improve visual functions, there is little desire for the patient to<br />
continue treatment. Moreover, the consequences of non-compliance are not<br />
felt immediately but are delayed by as long as several years. Thus, by nature,<br />
glaucoma is a perfect set up for non-compliance.<br />
The objective of this study was to assess self-reported compliance in glaucoma<br />
therapy in Eastern Indian population over a period of two years using a<br />
compliance questionnaire, and to identify factors interfering with compliance.<br />
MATERIALS AND METHODS<br />
This study is a population based retrospective study. 132 patients of Primary<br />
Open Angle <strong>Glaucoma</strong> (POAG), Primary angle closure or Ocular Hypertension<br />
(OHT), who attended glaucoma clinic in our hospital, were followed up from<br />
January 2008 to December 2009 at 3 monthly intervals. Patient demographics<br />
such as age, gender, education, employment, marital status and socioeconomic<br />
status were recorded. Medical history, information about disease,<br />
drop application habits and side effects were noted. All patients underwent<br />
complete examination including, best corrected visual acuity, slit lamp<br />
examination including examination with +90D lens, applanation tonometry,<br />
Humphrey visual field recording, and fundus photography. In each visit,<br />
patients were given questionnaire concerning the factors that may determine<br />
non-compliance. Non-compliance was defined as missing more than 2 doses<br />
of medications per week. Data was analysed using t-test and chi-square test.<br />
RESULTS<br />
132 patients, of which 70 were males and 62 females, with mean age 57(SD: 8.3)<br />
years were included in the study. At the first follow-up after 3 months, non-<br />
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compliance rate was 53% (70 patients), which improved to 9% (12 patients), at the<br />
final follow-up. On multivariate analysis, non-compliance was more common<br />
in those belonging to lower socio-economic status as compared to upper (OR<br />
4.84: 95%CI 1.28 to 15.2), and in patients with education less than high school<br />
level than those with education more than high school level (OR 2.50: 95% CI<br />
1.25 to 5.30). Non-compliance was also more common in OHT patients than in<br />
patients with glaucoma (OR 4.05: 95% CI 1.3 to 12.4). Although statistically not<br />
significant, non-compliance was more common in rural population than in<br />
urban population and among females as compared to males. Non-compliance<br />
was also more common in younger age group than in older patients<br />
Non- compliant<br />
Compliant<br />
Age 47+10.3 63+7.1<br />
Sex<br />
Female 32 30<br />
Male 30 40<br />
Education level<br />
Less than High Schools 34 23<br />
High School or more 28 47<br />
Socio-Economic Status<br />
Poor 44 24<br />
Good 18 46<br />
Stage of the disease<br />
Ocular Hypertension 25 10<br />
<strong>Glaucoma</strong> 37 60<br />
Residence<br />
Rural 40 42<br />
Urban 22 28<br />
Marital Status<br />
Single 13 10<br />
Married 49 60<br />
DISCUSSION<br />
In our study, non-compliant patients were mainly from lower socio-economic<br />
status who had difficulty in filling the prescriptions. Patients with education<br />
level less than high school were found to be less compliant as they had poor<br />
understanding of the disease. Younger patients and those who had ocular<br />
hypertension and early glaucoma had fairly poor compliance as they were<br />
underestimating the severity of their disease.<br />
The rate of non-compliance which was 53% at the first follow-up visit, improved<br />
progressively to 9% at the final follow-up. This shows the importance of proper<br />
counselling of the patients. Explaining the patients about the disease and<br />
consequences of lack of treatment, and medications, their actions and potential<br />
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side effects all helped in improving their compliance in subsequent visits.<br />
One of the most difficult challenges in treating glaucoma is ensuring patient<br />
compliance with glaucoma medication. The more active role we play in our<br />
patient’s management, the greater the success in treating this chronic and<br />
potentially sight-threatening disease.<br />
REFERENCES<br />
1. Ashbum F, Goldberg I, Kass M. Compliance with ocular therapy. Surv Ophthalmol.<br />
1980;24:237-46.<br />
2. James C. Tsai. Barriers to adherence with glaucoma therapy. Adv Stud Ophthalmol<br />
2007;4:72-5.<br />
3. Thomas J. Zimmerman, Alan H. Zalta. Facilitating patient compliance in glaucoma<br />
therapy. Survey of ophthalmol. 1983;28:252-7.<br />
4. Nordstrom BL, Friedman DS, Mozaffari E, Quigley HA, Walker AM. Persistence<br />
and adherence with topical glaucoma therapy. AM J Ophthalmol. 2005;140:598-606.<br />
Dr. VINAY KUMAR NANGIA B: MBBS (1980) and MS (1984) from<br />
Government Medical College, Nagpur University; Fellowship (1986), FRCS<br />
(1989), Royal College of Physician and Surgeon. Resident Ophthalmology,<br />
Royal Eye Hospital, Manchester, UK; Registrar and Clinical Tutor, Aberdeen<br />
University, UK; Presently Director, Suraj Eye Institute, Nagpur;<br />
Contact: 9890020804.<br />
Optic Disc Size and its Correlates in High<br />
Myopia in Central India<br />
Dr. Vinay Kumar Nangia B, Dr. Rajesh Gupta, Dr. Anshu Khare, Dr. Ajit<br />
Kumar Sinha<br />
The optic disc in myopia shows a variety of features. The disc size is<br />
known to vary significantly. 1 High myopes are thought to have large<br />
discs. 1 Myopic discs are also thought to be more predisposed to glaucoma<br />
and the association between myopia nad glaucoma is well recognized. 2,3,4 The<br />
appearance of the myopic disc, the rim and the cup differs from the optic disc<br />
seen in emmetropes. The presence of peripapillary atrophy similar to the Beta<br />
Zone is known to occur in myopies. The axial length is considered an important<br />
biometric parameter in myopia in addition to the corneal curvature. Data on<br />
the size of the optic disc in myopia from the India are not commonly available.<br />
The current study was done to determine the size of the optic disc in myopes<br />
in Central India and to determine its relationship with ocular parameters.<br />
MATERIALS AND METHODS<br />
73 eyes of 45 subjects (15 males) with a myopia of -8.00D or more underwent<br />
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an eye examination including vision, refraction, slit lamp evaluation,<br />
keratometry, Heidelberg Retina Tomography, applanation tonometry, central<br />
corneal thickness, pupillary dilation, optic disc photography. Confocal<br />
Scanning Laser Ophtalmoscopy was done using the HRT 2 (software version<br />
3). The optic disc contour line was drawn using the optic disc photograph<br />
as a guide. With the automatic reference plane, the computerized algorithm<br />
provides several values of optic disc morphometric parameters including<br />
optic disc area, cup area, cup disc ratio and retinal nerve fiber layer. Data<br />
were analysed using (PASWstatistics V.18)<br />
RESULTS<br />
The mean age was 33.00+-13.96 yrs. The mean spherical equivalent was<br />
-11.15+-2.96D, optic disc area was 2.20+- 0.69 mm2. (range 0.86-4.53). The<br />
mean rim area was 1.84+-0.63mm2, cup area ratio was 0.35+-0.39. The mean<br />
RNFL thickness was 0.19+-0.12 mm. The mean horizontal corneal diameter<br />
was 7.66+0.30mm and the mean vertical horizontal corneal diameter was<br />
7.5+0.31. The mean axial length was 27.42+1.9mm. The anterior chamber<br />
depth was 3.5+0.31mm. The lens thickness was 3.82+0.44 mm. and central<br />
corneal thickness was 530.79+43.33. The Optic disc area showed significant<br />
correlations in high myopic eyes with rim area (p
<strong>Glaucoma</strong> <strong>Free</strong> <strong>Papers</strong><br />
-8.00 Dioptres to be 2.2+-0.69 mm2. The mean The mean spherical equivalent<br />
was -11.15+-2.96D. The optic disc size did not show any correlation with myopic<br />
refractive error and with axial length, lens thickness or anterior chamber<br />
depth. The disc showed significant correlations with cup area and rim area.<br />
The finding of small optic disc in clinic based patients with high myopia<br />
differs from other studies. While it is important to understand that these are<br />
not a population based group of patients, yet the finding is significant. It is<br />
even more surprising that disc area in subjects with myopia of -8.00D or more<br />
did not show any correlation with axial length or refractive error.<br />
One of the important issues, is whether the measurements of Heidelberg<br />
Retina Tomography are valid at these high myopic dioptres since the range of<br />
refractive error varied from -20 to -8 D. However on clinical appearance the<br />
appearance of the discs is indeed small when viewed through a 78 D lens or<br />
on a photograph taken with the Zeiss FF450 fundus camera. It is possible that<br />
above a certain range in the Indian subcontinent, there may be parameters<br />
that may influence and be correlated with the size of the optic disc, other<br />
than axial length and refractive error. It may be important to study the<br />
relevance of this finding, specially since myopic disc are considered to be more<br />
predisposed to being glaucomatous and a smaller myopic disc may be even<br />
harder to diagnose.<br />
REFERENCES<br />
1. Jonas JB, Gusek GC, Naumann GO. Optic disc morphometry in high myopia.<br />
Graefes arch Clin Exp Ophthalmol 1988;226:587-90.<br />
2. Fong DS, Epstein DL, Allingham RR. <strong>Glaucoma</strong> and myopia are they related?.<br />
International Ophhalmol Clinics 1990;30:215-8.<br />
3. Seddon JM, Schwartz B, Flowerdew G. Case-Control study of ocular hypertension.<br />
Arch Ophthalmol 1983;101:891-4.<br />
4. Mitchell P, Hourihan F, Sandbach J, Wang JJ. The relationship between glaucoma<br />
and myopia: the Blue Mounains Eye Study. Ophthalmology 1999;106:2010-5.<br />
5. Britton RJ, Drance SM, Schulzer MD, et. Al. The area of the neuroretinal rim of the<br />
otpic nerve in normal eyes. Am J ophthalmol 1987;103:497-504.<br />
6. Jonas JB, Gusek GC, Naumann GOH: Optic Disc, cup and neuroretinal rim size,<br />
configuration, and corrlations in normal eyes. Invest Ophthalmol Vis Sci 29:1151-8.<br />
7. Jonas JB, Gusek GC, Naumann GOH: Optic disc morphometry in high myopia.<br />
GRaefes Arch Clin Exp Ophthalmol 1988;226:587-90.<br />
8. Varma R, Tielsch JM, Quigley HA, et al: Race, age, gender and refractive error<br />
related differences in the normal optic disc. Arch Ophthalmol 1994;112:1068-76.<br />
9. Vinay Nangia, Arshia Matin, Krishna Bhojwani, Maithili Kulkarni, Monica Yadav<br />
and Jost Jonas. Optic disc size in a population based study in Central India: The<br />
Central India Eye and Medical Study (CIEMS). Acta Ophthalmologica Scandinavia<br />
2008;86:103-4.<br />
383
69th AIOC Proceedings, Ahmedabad 2011<br />
Effect of Intraocular Bevacizumab on Visual<br />
Acuity and Intraocular Pressure in Neovascular<br />
<strong>Glaucoma</strong><br />
Dr. Pooja Prem Aggarwal, Dr. Balekudaru Shantha<br />
Neovascular glaucoma (NVG) is a unique form of secondary glaucoma,<br />
97% of the cases being caused by ocular ischemic disorders. 1 Diabetes<br />
mellitus, central retinal vein occlusion (CRVO) and ocular ischemic syndrome<br />
are the most common causes of NVG. 1,2 Numerous studies support the role<br />
of vascular endothelial growth factor (VEGF-A) in the pathogenesis of ocular<br />
neovascularisation 1,2 and have confirmed the increased levels of VEGF-A in<br />
NVG. 3 Hypoxia is responsible for the release, from ischemic tissue, of VEGF,<br />
a vasoproliferative substance that acts upon healthy endothelial cells of<br />
viable capillaries to stimulate the formation of a fragile new plexus of vessels<br />
(neovascularisation). Abnormal fibrovascular tissue grows on the iris and<br />
drainage angle structures including the trabecular meshwork, the contraction<br />
of which leads to progressive angle closure and intraocular pressure (IOP)<br />
elevation leading to glaucoma which is difficult to treat and has poor visual<br />
prognosis. Currently, this condition is managed by treating the underlying<br />
disease process and IOP reduction by medical and surgical therapy. Its<br />
management is complex and frequently requires the integrated use of<br />
medical, laser and surgical modalities. Bevacizumab (Avastin®; Genentech,<br />
Inc., South San Francisco, CA) is a recombinant humanized anti-VEGF A<br />
monoclonal IgG1 antibody that binds to and inhibits all isoforms of VEGF4<br />
and is approved by the US Food and Drug Administration for metastatic<br />
colorectal cancer in 2004. 5 There is evidence that specific inhibition of VEGF<br />
can inhibit neovascularization in the iris, choroid, cornea and retina. 6,7,8 The<br />
purpose of the current study is to evaluate the effect of intraocular (intravitreal<br />
or intracameral) bevacizumab (IOB) injection on visual acuity and IOP in cases<br />
of NVG.<br />
MATERIALS AND METHODS<br />
We retrospectively reviewed the medical records of 20 eyes of 18 patients who<br />
received IOB to treat NVG caused by ischemic retinal disorders including<br />
diabetic retinopahy(DR), CRVO, branch retinal vein occlusion (BRVO). All<br />
patients were treated at Sankara Nethralaya Hospital, Chennai from June 2006<br />
to January 2010. The mean follow up period was 177 days (176.62).<br />
The medical records of the patients were reviewed for age, gender, cause of<br />
NVG, any systemic illness, past ocular treatment, the best corrected visual<br />
acuity (BCVA), IOP, neovascularisation of the iris and angle, open or closed<br />
angle on gonioscopy, lens status, number of IOP lowering agents, the need<br />
384
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for pan retinal photocoagulation (PRP) or subsequent surgery. Best corrected<br />
visual acuity (BCVA), IOP levels and number of anti glaucoma medications<br />
(AGM) at the time of diagnosis and final visit were compared using the paired<br />
t-test. The success criteria was defined as IOP levels greater than 6 and less<br />
than 21 mm Hg with no further loss of vision(defined as >2 lines) at the final<br />
visit. Failure to treatment was defined as IOP >21 mm Hg despite use of AGM<br />
and loss of light perception. A P value
69th AIOC Proceedings, Ahmedabad 2011<br />
386<br />
12 PDR Diode 1.477 48 3 33 1.477 46 2<br />
CPC, ARC<br />
13 CRVO Diode 2.3 42 2 Diode 18 3.5 50 2<br />
CPC, ARC<br />
CPC+ARC<br />
14 VKH – 3.5 56 3 Diode CPC 346 4 – 0<br />
15 Others – 3.5 40 4 Diode CPC 447 4 10 3<br />
16 Others – 2.3 42 4 ENDO+ 458 3.5 20 3<br />
Diode CPC<br />
17 PDR PRP, 1 38 1 Trab+MMC 159 0.477 26 1<br />
Retinal<br />
Surgery<br />
18 PDR, PRP, 3.5 34 2 – 323 1.3 10 0<br />
BRVO Retinal<br />
Surgery<br />
19 CRVO IVB,PRP, 2.3 40 3 Diode CPC 68 2.3 11 2<br />
Diode CPC,<br />
TRAB,ARC<br />
20 CRVO PRP,ARC 2.3 17 2 Diode CPC 317 2.3 6 0<br />
IOB-intraocular bevacizumab, BCVA-best corrected visual acuity, IOPintraocular<br />
pressure, AGM anti glaucoma medication,PDR-proliferative<br />
diabetic retinopathy, CRVO-central reinal vein occlusion, PRP-panretinal<br />
photocoagulation, Trab+MMC- trabeculectomy with mitomycin C, CPCcyclophotocoagulation,<br />
ARC-anterior retinal cryppexy, IVB-intravitreal<br />
bevaciumab.<br />
DISCUSSION<br />
Currently, trabeculectomy with antimetabolite therapy, aqueous shunt<br />
implants, and trans-scleral laser cyclophotocoagulation are the preferred<br />
surgical treatment options, although the ideal surgical procedure is yet to<br />
be determined. 1 Performing any kind of filtering surgery or cyclodestructive<br />
procedure 9 in a patient with NVG and active NVI is associated with a<br />
significant risk of intraoperative and postoperative complications especially<br />
intraocular haemorrage and failure. Intraocular bevacizumab has been tried<br />
as an adjunct treatment modality in anterior chamber neovascularization<br />
of various etiologies 2,3,5,6 and the short term efficacy of intraocular injection<br />
on iris neovascularization and IOP is well proven. 12-14 Recent retrospective<br />
studies regarding intravitreal bevacizumab for iris neovascularisation and<br />
NVG showed that the IOP lowering effect for NVG was transient because of<br />
the drug’s short half life and the irreversible elevation of outflow resistance<br />
in the angle of NVG patients, requiring subsequent surgery to stabilize IOP<br />
levels. 10,11 Role of bevacizumab in the treatment of advanced NVG is limited<br />
to halting neovascular activities and may be a useful adjunct in the surgical<br />
treatment of NVG. In a retrospective case series 12 that included six eyes
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of three patients, all eyes manifested marked regression up to complete<br />
disappearance of iris and angle neovascularization after a single intravitreal<br />
injection. In three out of six eyes IOP decreased, whereas in the remaining<br />
patients IOP remained refractory and cyclophotocoagulation was needed.<br />
In another retrospective study including 41 eyes with significant Follow-up<br />
(13.3 months), Wakabayashi et al 10 concluded that intravitreal bevacizumab<br />
is well-tolerated, effectively stabilizing NVI and controlling IOP in patients<br />
with NVI alone or early-stage NVG without angle closure. In advanced NVG,<br />
intravitreal bevacizumab could not control IOP but could be used adjunctively<br />
to improve subsequent surgical results. 10<br />
Our study demonstrates the potential of intraocular bevacizumab to affect<br />
regression of new vessels and acts as an adjunct to other treatment modalities<br />
for NVG.<br />
In conclusion, bevacizumab affects the control of NVG by its indirect effect<br />
on the underlying pathologic process i.e. neovascularisation and aids in the<br />
success of the conventional treatment modalities which are associated with a<br />
high rate of failure .<br />
The limitations of this study were its retrospective nature and lack of a control<br />
group. Due to lack of a control group, we cannot speculate whether the<br />
observed results are due to IOB alone.<br />
REFERENCES<br />
1. Sivack-Callcott JA, O’Day DM, Gass JD, et al. Evidence based recommendations<br />
for the diagnosis and treatment of neovascular glaucoma. Ophthalmology.<br />
2001;108:1767–76.<br />
2. In:Allingham RA, Damji KF, <strong>Free</strong>dman S, et al, eds. <strong>Glaucoma</strong>s associated with<br />
disorders of the retina, vitreous and choroid. Shields’ Textbook of <strong>Glaucoma</strong>.<br />
Philadelphia: Lippincott, Williams and Wilkins 2005;5:328–46.<br />
3. Tripathi RC, Li J, Tripathi BJ, et al. Increased level of vascular endothelial growth<br />
factor in aqueous humor of patients with neovascular glaucoma. Ophthalmology.<br />
1998;105:232–7.<br />
4. Ferrara N, Hillan KJ, Gerber HP, Novotny W. Discovery and development of<br />
bevacimab, an anti-VEGF antibody for treating cancer. Nat Rev Drug Discov<br />
2004;3:391-400.<br />
5. Hurwitz H, Fehrenbacher L, Novotny W, et al. Bevacizumab plus irinotecan,<br />
fluorouracil, and leucovorin for metastatic colorectal cancer. N Engl J Med.<br />
2004;350:2335–42.<br />
6. Hayreh SS. Neovascular glaucoma. Prog Retin Eye Res. 2007;26:470–85.<br />
7. Ng WME, Anthony AP. Targeting angiogenesis, the underlying disorder in<br />
neovascular age-related macular degeneration. Can J Ophthalmol. 2005;40:352–68.<br />
8. Gaudreault J, Fei D, Rusit J, Suboc P, Shiu V. Preclinical pharmacokinetics<br />
387
69th AIOC Proceedings, Ahmedabad 2011<br />
of Ranibizumab (rhufabv2) after a single intravitreal administration. Invest<br />
Ophthalmol Vis Sci. 2005;46:726–33.<br />
9. Nabili S, Kirkness CM. Trans-scleral diode laser cyclophotocoagulation in the<br />
treatment of diabetic neovascular glaucoma. Eye 2004;18:352–6.<br />
10. Wakabayashi T, Oshima Y, Sakaguchi H, et al. Intravitreal bevacizumab to treat<br />
iris neovascularization and neovascular glaucoma secondary to ischemic retinal<br />
diseases in 41 consecutive cases. Ophthalmology 2008;115:1571–80.<br />
11. Moraczewski AL, Lee RK, Palmberg PF, et al. Outcomes of treatment of neovascular<br />
glaucoma with intravitreal bevacizumab. Br J Ophthalmol. 2009;93:589-93.<br />
12. Yazdani S, Hendi K, Pakravan M. Intravitreal bevacizumab (Avastin) injection for<br />
neovascular glaucoma. J <strong>Glaucoma</strong>. 2007;16:437–9.<br />
13. Silva Paula J, Jorge R, Alves Costa R, et al. Short-term results Of intravitreal<br />
bevacizumab (Avastin) on anterior segment neovascularization in neovascular<br />
glaucoma. Acta Ophthalmol Scand. 2006;84:556–7.<br />
14. Iliev ME, Domig D, Wolf-Schnurrbursch U, et al. Intravitreal Bevacizumab (Avastin)<br />
in the treatment of neovascular glaucoma. Am J Ophthalmol. 2006;142:1054–6.<br />
Biometry in Primary Angle Closure <strong>Glaucoma</strong><br />
Subjects and in a Population Based Study<br />
Dr. Ajit Kumar Sinha, Dr. Vinay Kumar Nangia B, Dr. Rajesh Gupta,<br />
Dr. Shubhra Agarwal, Dr. Karishma Bhate<br />
Quigley had estimated that by 2000 there would be 66.8 million people with<br />
primary glaucoma, with 6.7 million suffering from bilateral blindness.<br />
An estimated 8 million Asian Indians were projected to have glaucoma by<br />
the year 2000 with equal numbers of open angle and angle closure glaucoma<br />
(Quigley). 1<br />
In the urban population studied in south India among people 40 years of<br />
age or older 1.08% had manifest PACG and another 2.21% had occludable<br />
angles without ACG. 2 This prevalence is close to that reported recently in a<br />
Mongolian population. 3 Primary ACG is considered to be less frequent in the<br />
Caucasian white population. In APEDS 41.7% of those with manifest PACG<br />
had blindness in one or both eyes resulting from PACG. The study in Vellore<br />
in southern India reported the prevalence of PACG as 4.3% (95% CI, 3.0%-5.6%)<br />
and suggested the PACG was many times more common than POAG in that<br />
population. 4<br />
Biometric parameters are thought to play a part in the development of<br />
primary angle closure glaucoma. Several studies have suggested that eyes<br />
with occludable angles and angle closure glaucoma have shorter axial length,<br />
388
<strong>Glaucoma</strong> <strong>Free</strong> <strong>Papers</strong><br />
shallower anterior chambers and a thicker lens. 5-10 In a population based study<br />
in rural Tamil Nadu in southern India, eyes with primary occludable angles<br />
and primary angle closure glaucoma were found to have smaller axial lengths<br />
and shallow anterior chambers compared to normals. The differences were<br />
statistically significant. 9 Biometric parameters may play a role in the evolution<br />
and precipitation of the primary angle closure and primary angle closure<br />
glaucoma. This was a clinic-based study to assess the biometric parameters<br />
of eyes in Central India with a definite diagnosis of primary angle closure<br />
glaucoma in one or both eyes.<br />
MATERIALS AND METHODS<br />
88 eyes of 46 subjects with PACG were included. There were 16 males and<br />
30 females. The mean age was 59.12 +12.01 yrs. Visual Acuity was recorded<br />
in Digital units. (6/6=1). All subjects underwent an ophthalmic evaluation,<br />
including, applanation tonometry, gonioscopy with magna view single view<br />
lens (ocular instruments), sussman 4 mirror indentation gonioscope, biometry<br />
and optic disc evaluation with 78 Dioptre lens and indirect ophthalmoscopy<br />
for retinal assessment. Normative data were obtained from the Central India<br />
eye and Medical study from 4698 subjects and 9366 eyes. The details of<br />
methodology have previously been described for the CIEMS. 11 498 eyes of<br />
249 subjects were randomly included. There were 102 males and 147 females.<br />
Mean age was 49+6.59 yrs.<br />
RESULTS<br />
The mean values for biometry in the PACG subjects were axial length<br />
22.28+1.00 mm. Lens thickness, 4.49+0.70mm, anterior chamber depth<br />
2.56+0.54mm. The mean values from the population based CIEMS were for<br />
axial length 22.6+0.88, lens thickness 4.1+0.54 mm and anterior chamber depth<br />
3.15+0.36mm. The anterior chamber depth was significantly lesser in PACG<br />
(p
69th AIOC Proceedings, Ahmedabad 2011<br />
DISCUSSION<br />
We purposely selected only patients with a definite diagnosis of PACG as to<br />
identify associated biometric parameters and compared them to normals.<br />
There is evidence in literature to suggest that patients with PACG have shorter<br />
axial lengths, shallower anterior chambers and thicker crystalline lens. 5-10<br />
None of the PACG eyes studied was on pilocarpine therapy and therefore there<br />
was no possibility of any alteration of the normal anatomy. The normal eyes in<br />
our study appear to have axial lengths similar to the Chinese, white American<br />
and African American population and appear to be slightly larger than the<br />
population in Tamil Nadu. 9 Normative Data from the population based study<br />
performed in Central India was used for comparison. The average age of<br />
PACG patients was 59.12+12.01 yrs. (range 34-83) and of normals was 49+6.59<br />
yrs. (range 40-60). While the axial length may not change significantly with<br />
age, younger subjects may have thinner lenses and deeper anterior chambers.<br />
This may be kept in mind while considering the degree of difference in the<br />
biometric parameters between the two groups. Further there was a bigger<br />
age range as seen by the standard deviation in PACG patients. Increased lens<br />
thickness is known to be associated with increasing age. Our PACG patients<br />
showed a smaller axial length, shallower anterior chamber and increased<br />
lens thickness compared to normals. It appears that statistically significantly<br />
different biometric parameters are seen in patients of PACG, compared to<br />
normals in central India. These biometric parameters may together play a role<br />
in the pathogenesis and development of PACG. They may serve to identify<br />
patients with occludable angles and with primary angle closure who are at<br />
risk of developing PACG.<br />
REFERENCES<br />
1. Quigley HA. Number of people with glaucoma worldwide. Br J Ophthalmol<br />
1996;80:389-93.<br />
2. Dandona L, Deandeona R, Srinivas M, et al. Angle-Closure glaucoma in an<br />
urban population in southern India – the Andhra Pradesh Eye diseases Study.<br />
Ophthalmology 2000;107:1710-6.<br />
3. Foster PJ, Baasanhu J, Alsbirk PH, et al. <strong>Glaucoma</strong> in Mongolia. A population-based<br />
survey in Hovsgol province, northern Mongolia. Arch Ophthalmol 1996;114:1235-41.<br />
4. Jacob A Thomas R, Koshi SP, et. al. Prevalence of primary glaucoma in an urban<br />
south Indian population. Indian J Ophthalmol 1998;46:81-6.<br />
5. SaxenaS, Agrawal PK, Pratap VB et. al. Antgerior chamber depth and lens thickness<br />
in Primary Angle Closure glaucoma: a case control study. India J Ophthalmol<br />
1993;41:71-3.<br />
6. Panek WC, Christensen RE, lee DA, et. al. Biometric variables in patients with<br />
occludable anterior chamber angles. Am J Ophthalmol. 1990;110:185-8.<br />
390
<strong>Glaucoma</strong> <strong>Free</strong> <strong>Papers</strong><br />
7. Tomlinson A, Leighton DA, Ocular dimensions in the heredity of angle closure<br />
glaucoma. Br J Ophthalmol 1973;57:475.<br />
8. Lee DA, Brubaker RF, Illstrup DM. Anterior chamber dimensions in patients with<br />
narrow angles and angle closure glaucoma. Arch Ophthalmol 1984;102:46.<br />
9. George R, Paul PG, Baskaran M, et.al. Ocular biometry in occludable angles and<br />
angle closure glaucoma: a population based survey. Br J Ophthalmol 2003;87:399-<br />
402.<br />
10. Marchini et.al. Ocular dimensions of PACG. Ophthalmology 1998;105:2091-8.<br />
11. Vinay Nangia, Jost B. Jonas, Ajit Sinha, Arshia Matin, Maithili Kulkarni,<br />
Songhomitra Panda-Jonas. Ocular Axial length and its Associations in an Adult<br />
Population of Central Rural India. The Central India Eye and Medical Study.<br />
Ophthalmology 2010;117:1360-6.<br />
Dr. ARIJIT MITRA: MBBS (1997), Nilratan Sircar Medical College and<br />
Hospital, WBUHS; DO (2005), Medical College Kolata, WBUHS; DNB<br />
(2007), Aravind Eye Hospital and Post Graduate Institute of Ophthalmology,<br />
National Board of Examinations, New Delhi. Presently, <strong>Glaucoma</strong> Fellow at<br />
Aravind –Zeiss Centre for Excellence in <strong>Glaucoma</strong> at Aravind Eye Hospital,<br />
Tirunelveli. E-mail: jeet2712@yahoo.co.in<br />
AGV in Refractory <strong>Glaucoma</strong>-Outcome,<br />
Complications and Management of<br />
Complications—Single Surgeons Experience<br />
Dr. Arijit Mitra, Dr. Ramakrishnan R, Dr. Mohindeen Abdul Kadar P M,<br />
Dr. Anup Das, Dr. Ashish Kumar<br />
To study the outcome of Ahmed <strong>Glaucoma</strong> Valve in cases of refractory<br />
glaucoma.<br />
<strong>Glaucoma</strong> drainage implants are an useful alternative in treating glaucomas<br />
that are resistant to medical therapy and glaucoma filtration surgery. They<br />
have now assumed an important place in our surgical armamentarium for<br />
the treatment of complicated and refractory glaucomas both as a primary<br />
surgical modality and as a secondary procedure where trabeculectomy with<br />
or without adjunctive antimetabolite therapy has either failed or is reported to<br />
have a very low chance of success.<br />
<strong>Glaucoma</strong> drainage implants that have been used extensively include<br />
the nonrestrictive glaucoma drainage devices like Molteno implant, the<br />
Baerveldt implant and the Schocket tube shunt, and the valved, restrictive<br />
drainage devices like the Krupin Denver Valve and the Ahmed <strong>Glaucoma</strong><br />
Valve implants. This study describes our clinical experience with the Ahmed<br />
<strong>Glaucoma</strong> Valve implant in Indian eyes with glaucoma that was refractory to<br />
conventional medical/ laser and surgical treatment.<br />
391
69th AIOC Proceedings, Ahmedabad 2011<br />
MATERIALS AND METHODS<br />
Records of patients who were treated with the Ahmed <strong>Glaucoma</strong> Valve implant<br />
for increased intraocular pressure or glaucoma that was not responsive to<br />
medical treatment, laser treatment, or previous glaucoma surgery were<br />
reviewed. A total of 26 patients (26 eyes) were included in our study. Patients<br />
with less than 4 months of follow-up were excluded from the analysis.<br />
After informed written consent was obtained, the Ahmed <strong>Glaucoma</strong> Valve was<br />
implanted in all cases by a single surgeon Dr. R.K. Patients with neovascular<br />
glaucoma were treated with panretinal photocoagulation before the Ahmed<br />
<strong>Glaucoma</strong> Valve was implanted, when feasible.<br />
Documentation of the following information was carried out for each<br />
patient regarding: age, gender, detailed clinical history along with general<br />
physical, and systemic examination; a comprehensive ocular examination<br />
including quantitative recording of best corrected visual acuity (BCVA) using<br />
Snellens charts, a thorough anterior and posterior segment examination, IOP<br />
measurement with Goldmann applanation tonometer and gonioscopy with<br />
a Goldmann four mirror gonioprism and recording of visual fields using<br />
automated perimetry by Humphrey field analyser.<br />
The primary outcome variable was considered to be successful control of the<br />
elevated IOPs after surgery. Absolute success was defined as an IOP less than<br />
or equal to 22mmHg and more than 5mmHg with no additional glaucoma<br />
surgeries or visually devastating complications postoperatively. Although<br />
postoperative use of antiglaucoma medications was not a criterion for absolute<br />
success or failure, qualified success was defined as IOP less than 22mmHg and<br />
more than 5mmHg with the use of antiglaucoma medications.<br />
Till the IOP was controlled by a maximum of 2 topical and/or 1 systemic<br />
antiglaucoma medication the surgery was not considered to be a failure.<br />
Systemic antiglaucoma medications were used subsequent to the use of the<br />
topical medications. The last follow-up was noted as the last time the patient<br />
was seen or the time at which the surgery failed by our success criteria.<br />
The data were statistically evaluated using student’s t test and paired t-test for<br />
quantitative data and Pearson’s χ2 test for qualitative data as indicated and the<br />
cumulative probability of success was examined by Kaplan–Meier life-table<br />
analysis.<br />
RESULTS<br />
The mean IOP at baseline was 32.37±7.86 mm of Hg and that after the operation<br />
was 12.57±8.86 mm of Hg at 1 week post surgery and 17.42±3.57 mm of Hg at 12<br />
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months post surgery. Pre-and postoperative IOP differences were statistically<br />
significant at all examination periods (P
69th AIOC Proceedings, Ahmedabad 2011<br />
Table 6 :Intraocular Pressure profile before and after placement of<br />
AGV Implant<br />
Time Mean IOP SD Minimun IOP Maximum IOP<br />
(mm Hg) (mm Hg) (mm Hg) (mm Hg)<br />
Pre operative 32.37 7.86 24 64<br />
1 w 12.57 8.86 2 28<br />
1m 19.67 8.95 4 38<br />
2m 20.74 8.88 4 47<br />
4m 18.88 6.70 6 52<br />
6m 17.44 5.88 2 46<br />
12 m 17.42 3.57 4 47<br />
Table 7: Visual Acuity<br />
S No Post op VA Number Percentage<br />
1 Improved or within one Snellen line 23 88.46<br />
2 Worse by more than one Snellen line 3 11.54<br />
Table 8: Success and Failure<br />
S no Success/Failure Number Percentage<br />
1 Complete success 3 11.54<br />
2 Qualified success 19 73.08<br />
3 Failiure 4 15.38<br />
Table 9: Complications after AGV Insertion<br />
S.No Complication Number Percentage<br />
1 Hyphaema 4 15.38<br />
2 Shallow AC 3 11.54<br />
3 Choroidal effusion 2 7.69<br />
4 Plate exposure with leak 1 3.85<br />
5 Scleral patch graft exposure 2 7.69<br />
6 Tube exposure 3 11.54<br />
7 Tube Block 1 3.85<br />
8 Diplopia 1 3.85<br />
Table 10: Management of Complications<br />
S No Complication Management<br />
1 Plate exposure with leak Conjunctival autograft<br />
2 Scleral patch graft exposure Regrafting with anchoring sutures<br />
3 Tube exposure Repositioning and reinforcement with scleral<br />
patch graft<br />
4 Tube block Nd YAG vitreolysis<br />
5 Diplopia Valve removal with replacement<br />
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Table 11: Additional Procedures<br />
S No Procedure Number Percentage<br />
1 5 FU administration 2 7.69<br />
2 Conjunctival autograft 1 3.85<br />
3 Re scleral patch grafting with anchoring sutures 2 7.69<br />
4 Repositioning and reinforcement with scleral patch graft 3 11.54<br />
5 Valve removal with replacement 1 3.85<br />
Table 12: <strong>Glaucoma</strong> Medication profile before and after placement of<br />
Ahmed <strong>Glaucoma</strong> Valve<br />
Time Mean number SEM<br />
Pre operative 2.74 0.14<br />
1 w 0.24 0.06<br />
1 m 0.66 0.11<br />
2 m 0.68 0.11<br />
4 m 0.71 0.12<br />
6 m 0.75 0.11<br />
12 m 1.10 0.13<br />
SEM Standard error of the mean.<br />
DISCUSSION<br />
A variety of aqueous drainage implants have been developed to treat<br />
recalcitrant glaucomas, including open tube and valved designs. 1,2 The AGV<br />
implant has a 185-mm2 polypropylene body, which is larger than the singleplate<br />
Molteno implant and smaller than the Baerveldt implant. Its tapered<br />
chamber valve is designed to provide resistance to aqueous flow.<br />
In our study, a successful outcome was achieved in the majority of eyes<br />
at the most recent follow-up examination, although most eyes required<br />
approximately one antiglaucoma medication postoperatively. The overall<br />
success rate in this study compares favorably with the success rates of other<br />
glaucoma drainage devices. The Molteno implant has had success rates of 58%<br />
to 95% 3-5 and success rates of 64% and 80% were reported with the Krupin-<br />
Denver valve with disk. 6,7<br />
A period of transient elevation of intraocular pressure, termed the<br />
“hypertensive phase,” has been described after glaucoma drainage implant<br />
surgery, appearing approximately 4 weeks after surgery and lasting at least<br />
12 to 16 weeks. 8 In our study, the peak mean intraocular pressure 2 months<br />
postoperatively was significantly higher than the intraocular pressure at 1 and<br />
2 years after surgery. This moderate hypertensive phase may be due to the<br />
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intermediate-sized plate of the Ahmed <strong>Glaucoma</strong> Valve implant.<br />
In our Kaplan-Meier life-table analysis, the cumulative probability of success<br />
following Ahmed <strong>Glaucoma</strong> Valve implant was 84.75% at 6 months and 79.83%<br />
at 12 months.<br />
We found certain complications in a number of patients following this surgical<br />
procedure. Most of the patients were treated conservatively and the early<br />
complications resolved. However certain complications required an additional<br />
surgical procedure to be performed. Seven cases (7/26, 26.92%) required<br />
another surgical intervention where a fresh conjunctival graft or a scleral<br />
patch graft or a valve removal and repositioning had to be done. This number<br />
may seem high considering the few cases included in the study but it must be<br />
kept in mind that almost all the case selected in this study had a history of a<br />
single or more filtering surgeries done previously which had failed over time.<br />
Thus the conjunctiva and the eye per se were already in a compromised state<br />
at the point of being selected for the study.<br />
Thus to conclude it can be said that AGV was found to be very effective in<br />
the management of refractory glaucomas of various etiologies. There may<br />
however be certain complications in cases where AGV was not being done as a<br />
primary procedure but the complications can be managed effectively and the<br />
success outcomes are favorable in case of these refractory glaucomas.<br />
REFERENCES<br />
1. Williams AS. Setons in glaucoma surgery. In: Albert DM, Jakobiec FA, editors.<br />
Principles and practice of ophthalmology: clinical practice. Philadelphia: WB<br />
Saunders 1994:1655–67.<br />
2. Rosenberg LF, Krupin T. Implants in glaucoma surgery. In: Ritch R, Shields MB,<br />
Krupin T, editors. The glaucomas, Philadelphia: Mosby, 1996;2:1783–807.<br />
3. Melaned S, Cahane M, Gutman I, Blumenthal M. Postoperative complications after<br />
Molteno implant surgery. Am J Ophthalmol 1991;111:319-22.<br />
4. Minckler DS, Heuer DK, Hasty B, et al. Clinical experience with the single-plate<br />
Molteno implant in complicated glaucomas. Ophthalmology 1988;95:1181–8.<br />
5. Lloyd MA, Sedlak T, Heuer DK, et al. Clinical experience with the single-plate<br />
Molteno implant in complicated glaucomas: update of a pilot study. Ophthalmology<br />
1992;95:679–87.<br />
6. Fellenbaum PS, Almeida AR, Minckler DS, et al. Krupindisk implantation for<br />
complicated glaucoma. Ophthalmology 1994;101:1178–82.<br />
7. The Krupin Eye Valve Filtering Surgery Study Group. Krupin eye valve with disk<br />
for filtration surgery. Ophthalmology 1994;101:651–8.<br />
8. Lieberman MF, Ewing RH. Drainage implant surgery for refractory glaucoma. Int<br />
Ophthalmol Clin 1990;30:198–208.<br />
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Dr. TANUJA KATE: MBBS (1995), MGM Medical College, Indore; MS<br />
(2000), NSCB Medical College, Jabalpur. Observership in <strong>Glaucoma</strong> (2006)<br />
from New York Eye Hospital, USA. Observership in <strong>Glaucoma</strong> (2008) from<br />
Aravind Eye Hospital, Madurai. Fellowship in Medical Retina (2006) from<br />
Manhattan Eye Hospital, USA. Presently, Consultant (<strong>Glaucoma</strong>), Rajas<br />
Eye Hospital, Indore. E-mail: tanuja_121@rediffmail.com<br />
Neovascular <strong>Glaucoma</strong> – IOP Control by<br />
Avastin and Subsequent Trabeculectomy with<br />
Mitomicin-C<br />
Dr. Tanuja Kate, Dr. Jyoti Singhyai, Dr. Navita Mittal, Dr. Rajiv Choudhary<br />
Neovascular <strong>Glaucoma</strong> (NVG) is a severe form of glaucoma with<br />
devastating visual outcome attributed to new blood vessels obstructing<br />
aqueous humour outflow usually secondary to widespread posterior segment<br />
ischaemia. It is a severely blinding intractable disease. To prevent or reduce<br />
the extent of visual loss caused by NVG, the first essential is to have a high<br />
index of suspicion of its development.<br />
Once diagnosed, PRP is the first line of therapy in almost all cases of<br />
NVG. But if it is not possible due to hazy media then surgical treatment is<br />
attempted first. Trabeculectomy has a high risk of intra operative bleeding<br />
and postoperative failure. It can be overcome by pre – operative use of Avastin<br />
and then Trabeculectomy with the use of anti fibrotic agent. The present study<br />
aimed to evaluate safety and extent of IOP control by Avastin followed by<br />
Trabeculectomy augmented with mitomicin-C (MMC) in the management of<br />
NVG.<br />
MATERIALS AND METHODS<br />
It was an observational retrospective study of 10 cases of NVG. The cases<br />
included had IOP not controlled with laser photocoagulation alone and<br />
cases where photocoagulation was not possible at the time of presentation.<br />
We excluded the cases with history of crerebrovascular accident and cardiac<br />
illness. At the time of presentation panretinal photocoagulation (PRP) had<br />
already been done in 6 cases.<br />
Avastin was given intravitreally or Intravitreally + Intracamerally, the dose<br />
being 1.25 mg through each route.<br />
After 1 wk of Avastin injection, the case was subjected to trabeculectomy<br />
augmented with mitomicin–C (0.2 mg/ml) subsclerally for 1 mt. Baseline<br />
IOP, IOP after 1 wk of avastin and then IOP postoperatively at day 5, 15, 1<br />
month and 2 months was recorded by applanation tonometer. At 1 month<br />
postoperative period, laser photocoagulation was done in patients depending<br />
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upon comprehensive ocular status .<br />
Complete success was labeled to cases with IOP 6 – 21 mm Hg without<br />
glaucoma medication and qualified success to cases with IOP 6 –21 but with<br />
glaucoma medication.<br />
Observation<br />
Total No. of Cases 10.<br />
Table 1: Age Distribution<br />
Age Group<br />
41 – 50 2 (20%)<br />
51 – 60 5 (50%)<br />
61 – 70 2 (20%)<br />
71 – 80 1 (10%)<br />
Table 2: Sex Distribution<br />
Sex<br />
Male 7 (70%)<br />
Female 3 (30%)<br />
Table 3: Cause of NVG<br />
Cause<br />
No. of Patients<br />
No. of Patients<br />
No. of Cases<br />
Central Retinal Vein Occlusion 3 (30%)<br />
Diabetic Retinopathy 6 (60%)<br />
Branch Retinal Artery Occlusion 1 (10%)<br />
Table 4: Visual Acuity at the time of Presentation<br />
Visual Acuity<br />
No. of Cases<br />
PL – HM 3 (30%)<br />
CF – 6/60 4 (40%)<br />
6 / 36 – 6/12 3 (30%)<br />
Table 5: Descriptive Statistics of IOP (mmHg)<br />
IOP at IOP IOP IOP IOP IOP<br />
Presen- Post 5th Post 15th 1 month 2 months<br />
tation Avastin Operative POD<br />
Day (POD)<br />
Mean 46.00 41.40 25.00 18.20 16.60 16.60<br />
Std. Deviation 5.96 4.99 7.96 3.19 1.90 1.90<br />
Median 46.00 40.00 21.00 18.00 16.00 16.00<br />
Minimum 38.00 36.00 18.00 14.00 14.00 14.00<br />
Maximum 54.00 50.00 42.00 26.00 20.00 20.00<br />
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Table 6: Student – Newman-Keuls: Pair wise comparison of IOPs (Yes<br />
indicates significant at 5%.)<br />
IOP at IOP IOP IOP IOP IOP<br />
Presen- Post 5th Post 15th 1 month 2 months<br />
tation Avastin POD POD<br />
IOP at Presentation No Yes Yes Yes Yes<br />
IOP Post Avastin No Yes Yes Yes<br />
IOP 5th POD No Yes Yes<br />
IOP 15th POD No No<br />
IOP 1 month<br />
Table 7: Complications of Treatment Strategy<br />
Complication<br />
Post Operative Hypotony 0 (0%)<br />
No. of Cases<br />
Shallow A.C. 1 (10%)<br />
Hyphaema 2 (20%)<br />
Choroidal Detachment 0 (0%)<br />
Epithelial Corneal Erosion 0 (0%)<br />
Conjunctival Dehiscence 0 (0%)<br />
RESULTS<br />
The inference drawn from table 5 is that the mean IOP is declining as compared<br />
baseline. The non parametric test (Friedman’s test) when applied to table No. 5,<br />
P value was 0.00 meaning the change in IOP was significant.<br />
Table 6 infers that post avastin IOP doesn’t differ from IOP at presentation<br />
significantly. However, the difference between post avastin IOP and<br />
postoperative (Day 15, 1 month and 2 months) IOP is significant. Thus surgery<br />
resulted in significant decline in IOP.<br />
Complete success of the procedure was seen in 6 (60%) cases while qualified<br />
success in 4 (40%) cases.<br />
DISCUSSION<br />
NVG is a serious complication of systemic and retinal diseases. The IOP can<br />
rise rapidly often resulting in extremely high IOP with irreversible and severe<br />
loss of vision. Early PRP for neovascularization is necessary to ameliorate the<br />
devastating sequelae from NVG. However, as in our study, few cases might<br />
present with such a high IOP and hazy media (due to corneal haze and / or<br />
vitreous haze) that PRP as a first measure is not possible.<br />
According to Rauscher et al intravitreal Bevacizumab (Avastin) is a temporizing<br />
measure for causing regression of iris and angle neovascularization (NVI and<br />
No<br />
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69th AIOC Proceedings, Ahmedabad 2011<br />
NVA). In our study also, patients were subjected to surgical intervention after<br />
1 wk of Avastin, so that NVI and NVA regress thereby reducing the incidence<br />
of intra operative bleeding and post operative hyphaema.<br />
In our study mean IOP reduced from 41.40 mm Hg (Post Avastin but<br />
preoperative) to 16.60 mm Hg at 1 month post operative period. This is<br />
supported by a study by Alkawas, Ayman A. etal wherein mean IOP reduced<br />
from 42.9 ± 4.2 mm Hg to 16.3 ± 2 mm Hg at 1 month post operative period. In<br />
the same study shallow A.C. was seen in 11.8% cases and hyphaema in 23.5%<br />
cases. In our study also shallow A.C. was seen in 10% causes and hyphaema<br />
in 20% cases.<br />
Horsley MB et al in their study conclude that anti VEGF agents lead to regression<br />
of both NVI and NVA and IOP control when the angle remains open. And this<br />
point is supported by present study as Avastin injection resulted in mean IOP<br />
reduction from 46 mm Hg to 41.40 mm Hg which is not a significant reduction,<br />
the reason being angle was closed.<br />
The statistical analysis of the present study concludes that surgery results<br />
in significant decline in IOP. Although post Avastin IOP is lower but it is<br />
not significantly different from IOP at presentation. Thus, avastin might be<br />
catalysing the decline which was difficult to prove in the present study as we<br />
didn’t study NVG patients without avastin and only surgery.<br />
Trabeculectomy with MMC after an adjunctive treatment with intravitreal<br />
with or without intracameral Avastin is a safe and effective modality of<br />
controlling IOP in NVG. Thus Avastin extends our therapeutic options in the<br />
management of NVG.<br />
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