5 months ago

April 2018


SPECIAL FEATURE: RANZCO 2018 Calling all Kiwi doctors to AUSCRS 2018 BY DR DAVID KENT* This year’s annual meeting of the Australasian Society of Cataract and Refractive Surgeons (AUSCRS) will be held at Macquarie Conference Centre, Peppers (previously known as the Outrigger), Noosa from Wednesday 17 October to Saturday 20 October. Since its beginnings in 1996, AUSCRS has been the only local Australian and New Zealand annual meeting devoted to cataract and refractive surgery. Despite this, it remains poorly attended by New Zealand ophthalmologists many of whom are refractive surgeons and almost all of us are cataract surgeons. I’d like to encourage more attendance at our local meeting by New Zealand-based ophthalmologists many of whom would find this a useful and very enjoyable meeting to attend. AUSCRS is a much less formal meeting than either the American or European cataract and refractive surgery meetings. Dress has always been casual with no jackets, suits or ties and the meeting has always intentionally been held at “resort” destinations in Australia and New Zealand, making it very “family friendly” to attend. The relaxed and friendly atmosphere, is also more than complemented by the high calibre of speakers drawn from across the world and locally. There’s lots of discussion and debate, and plenty of opportunity to freely discuss topics with both internationally-renowned and local experts, truly unrivalled by similar meetings. Another annual AUSCRS highlight and tradition is the imaginative themes and formats of the sessions, with local and international speakers often dressing up in entertaining costumes, sometimes bordering on the bizarre. It has been very entertaining over the years to see world-renowned YEARS Complete Cataract, Refractive & IOL workstation • Pentacam ® measurements The ‘gold standard’ for measureing and analysing the anterior segment of the eye • Axial measurements For IOL power calculations Barrett Formulas The Barrett formulas are now integrated in the IOL Calculator of the Pentacam ® AXL. The update incorporates the Barrett Universal II, Barrett Toric and Barrett True K. Drs Dean Corbett, Peter Ring, Michael Merrimen and David Kent demonstrating the more relaxed attire favoured at AUSCRS at the 2015 conference in Noosa ophthalmologists dressed up in amusing costumes debating often quite controversial topics. Some New Zealand ophthalmologists appear to be put off attending AUSCRS because of a perception the meeting is largely for refractive surgeons. This has never been the case and most of the meeting remains primarily concentrated on advances in cataract surgery. So any New Zealand ophthalmologist who performs cataract surgery would also find AUSCRS a very useful meeting to attend. Another unique part of AUSCRS is the advanced trainee session on the Wednesday morning where some of the leading Australasian cataract OCULUS PENTACAM ® AXL See DFV at RANZCO 2018 Premium IOL in four easy steps: 1. overall corneal astigmatism 2. total corneal spherical aberrations 3. total corneal irregularities 4. the influence of the posterior corneal surface IOL Caclulator Noosa, venue for AUSCRS 2018 and refractive surgeons present a series of educational lectures and interactive sessions for senior registrars and fellows. Feedback from registrars has always been very positive for this programme. The conference-proper starts with an opening street party on Wednesday evening, then there are three days of academic sessions on Thursday, Friday and Saturday with the Gold Medal Lecture on Thursday morning. The meeting finishes with the AUSCRS Gala Event on Saturday night, leaving Sunday for delegates to sight-see and travel home. The overseas speakers are yet to be announced for this year’s AUSCRS, but usually include some of the world’s leading cataract and refractive surgeons. Professor Graham Barrett continues to preside over AUSCRS and there really isn’t anyone better in Australasia with the experience and academic mana to be the leader of our local cataract and refractive surgery meeting. I believe most New Zealand ophthalmologists should consider attending AUSCRS as they will truly enjoy it and find the calibre of education second-to-none. We should also all be supporting this ‘local’ meeting to keep it sustainable in the long term. So, I hope you’ll join me at AUSCRS 2018 in Noosa this October. For more: please visit *Dr David Kent is a consultant ophthalmologist with Fendalton Eye Clinic and Christchurch Eye Hospital. He has co-authored many papers and presented at many international meetings on laser refractive surgery. He is a member of both the American and Australasian Societies of Cataract and Refractive Surgery, and the New Zealand AUSCRS council representative. VR training at RVEEH KERATOGRAPH 5M DV931-0318 OCULUS Oculus Keratograph 5M is the essential corneal topography and dry eye analysis tool for your practice. Diagnostic Dry Eye Assessment Complete suite of imaging modes Meibo-scan Infra Red LED TF-Scan Non invasive tear breakup analysis Topography Imaging Blue & White LED R-scan Auto redness grading Learn how Keratograph 5M can assist with advanced screening of dry eye patients for cataract and refractive surgery. 0800 338 800 Mobile: 021 990 200 Email: The ONLY system to offer: Spherical, Toric, Post-Refractive and Total Cornea calculations. OCULUS CORVIS ® ST Biomechanical Properties of the Cornea,Tonometry and Pachymetry, for cataract and refractive surgery. • True IOP measurement after refractive surgery • Improved prediction of refractive outcome • Glaucoma risk assessment • Visualisation of the effect of corneal cross-linking • Screening for keratoconus, ectasia and combine with Pentacam/AXL for even greater sensitivity. Dr Jacqui Beltz overseeing new VR training at RVEEH The Royal Victorian Eye and Ear Hospital (RVEEH) has introduced state-of-the-art virtual reality simulators to train the next generation of eye surgeons. The RVEEH’s new Eyesi Surgical simulators allow ophthalmology trainees to learn highly specialised micro-surgery skills in a safe and controlled environment, and the trainer to objectively monitor and track an individual’s progress, said Dr Jacqueline Beltz, RVEEH ophthalmologist and training director for the Victorian Branch of RANZCO. “Practice is vital to learn any skill and microsurgery is no exception. Virtual reality simulation provides a setting that forgives failure, and allows trainees to develop fine motor skills as well as learn from their errors without causing harm.” Studies have shown that patient outcomes are improved when trainees have undertaken virtual reality training. Virtual reality simulation training will be used alongside traditional training methods, including wet and dry labs, to increase the breadth of surgical training for young ophthalmologists, said Dr Beltz. “With the data that is collected, we can track each individual trainee’s progress, identifying and addressing any gaps that may require extra practice or additional teaching. We can also compare trainees’ progress both locally and globally, so we can evaluate and improve our training programme.” The first stage of RVEEH’s virtual reality training programme will focus on preparing first year trainees for cataract surgery. Future programmes will include training for vitreoretinal surgery and complication management. ▀ 18 NEW ZEALAND OPTICS April 2018

Case study: Mycobacterium chelonae keratitis following cataract surgery BY DR LUCY LU, DR JENNIFER COURT AND PROFESSOR CHARLES MCGHEE* Here we present a rare case of postcataract surgery and corneal wound infection caused by the non-tuberculous mycobacterium species Mycobacterium chelonae. This case illustrates the difficulties in diagnosis and treatment of this uncommon condition to increase awareness of this potentially devastating infection among optometrists and ophthalmologists. Case history A usually fit and well, 85-year-old, New Zealand European female presented with redness, pain and reduced vision in her left eye, eight weeks after routine, uncomplicated, cataract phacoemulsification with intraocular lens implantation. Visual acuity OS at presentation was reduced to 6/30 unaided, 6/15 with pinhole (previously 6/7.5 corrected post-op). The left cornea had a 1.0 x 2.8mm stromal infiltrate in the temporal clear corneal wound site, without an overlying epithelial defect. The anterior chamber exhibited 2+ cells but no hypopyon. The vitreous was quiet and the fundus examination was normal. She was admitted to hospital and treated with intensive topical antibiotic drops (hourly cefuroxime 5% and tobramycin 1.36%). However, the intraocular inflammation worsened so she underwent anterior chamber washout, vitrectomy and administration of intravitreal antibiotics (ceftazidime and vancomycin). Oral doxycycline, ciprofloxacin and prednisone were added. Surprisingly, aqueous and vitreous samples were entirely negative for bacterial and fungal culture as well as for viral PCR. After slow improvement, she was discharged on day 16 on topical ciprofloxacin and prednisolone 1%. She was monitored closely as an outpatient and the infection waxed and waned over the subsequent two months (Figs 1 and 2). A large corneal biopsy also failed to identify any causative organism. Therefore, after 13 weeks of treatment, ciprofloxacin was cautiously tapered and stopped, however, the infection recurred with greater severity with an overlying corneal melt and the prospect of corneal perforation. Subsequently, a superficial keratectomy, accompanied by a focal, partial-thickness, tectonic corneal graft (5mm), was performed to excise the majority of the lesion, approximately four months after initial presentation. Two weeks later, white flecks were noted in the graft-host-interface (Fig 3) and a rapidly growing mycobacterium species, Mycobacterium chelonae was also isolated from the superficial keratectomy. This isolate was notably resistant to ciprofloxacin and doxycycline, but sensitive to clarithromycin, tobramycin and linezolid on standard MIC (mean inhibitory concentration) testing. Therefore, intensive topical tobramycin and linezolid were started, and topical prednisolone withheld. Despite intensive, appropriate, dual-antibiotic topical treatment the inflammation increased and the overlying graft became oedematous and opaque (Figs 4a and 4b). Consequently, the lamellar graft was removed to reduce the infective load and allow better drug penetration to the underlying host cornea. After an extended two-month course of treatment, the infection gradually settled, almost 10 months after her initial cataract surgery (Fig 5). Her vision at this stage was 6/15 unaided, 6/9 pinhole and her eye was comfortable. She is expected to continue on low dose topical antibiotics, under close monitoring, for up to a year. Discussion Non-tuberculous mycobacteria (NTM) refers to a group of Mycobacterium species other than the Mycobacterium tuberculosis complex. NTM exist ubiquitously in the environment including in soil and drinking water. They are rare causes of systemic and ocular infections, particularly related to trauma and surgery 1 . The Mycobacterium chelonae species is an insidious yet aggressive pathogen that has been reported as a devastating cause of post-LASIK and post-cataract surgery keratitis and endophthalmitis 2-6 . There are several cases of Mycobacterium chelonae keratitis after clear cornea cataract surgery reported in the literature, many requiring significant intervention such as corneal transplant, but typically with poor visual outcomes 4-6 . Known risk factors for developing mycobacterial keratitis include trauma, ocular surgery, poor tear film integrity, inappropriate use of topical corticosteroids and contact lens use 4 . Systemic conditions such as diabetes mellitus or immunosuppression increase the susceptibility to infection. Our patient did not have any of these risk factors, other than routine postoperative steroid drops. Fig 1. Recurrence of dense stromal infiltrate at the temporal clear corneal wound with keratic precipitates, two weeks after discharge from hospital, while on treatment with topical ciprofloxacin Fig 4a. Progessive infection with development of interface fluid affecting the temporal, lamellar tectonic corneal graft with loosening of sutures (6 weeks post-op) Fig 5. After two months of continuous topical Linezolid and Tobramycin, the base of the previous patch graft site had epithelialised and was clinically free of infection Post-operative Mycobacterium chelonae keratitis has an insidious onset, with variable time between surgery and onset of symptoms, from days to months. The affected cornea may exhibit a “cracked windshield” appearance around the edges of a stromal infiltrate, often without an overlying epithelial defect. Infiltrates may have irregular margins or stellate lesions, mimicking a fungal keratitis 1 . NTM infections are particularly dangerous because most routinely used topical antibiotics are ineffective against them, and antibiotic resistance is a significant issue 7 . A review of in vitro microbiological susceptibilities of NTM showed the following susceptibilities: clarithromycin (93%), amikacin (81%), linezolid (36%), moxifloxacin (21%), and ciprofloxacin (10%). In the M. abscessus/chelonae subgroup, only 1% were susceptible to ciprofloxacin 8 . In addition, Mycobacterium chelonae can be difficult to culture, with fastidious growth requirements, which increases the risk of false negative reports and delayed diagnosis as in this case 7 . Mycobacteria keratitis requires aggressive treatment, ideally with multiple fortified topical antibiotics with consideration of systemic cover (such as oral clarithromycin) if severe 7, 8 . An extended treatment course is required. As illustrated in the presented case, Mycobacterium chelonae keratitis can take a prolonged, waxing and waning course that may falsely reassure the clinician of impending resolution. Negative corneal scrapes in a nonresponding infection warrants surgical biopsy to enable correct diagnosis and prevent complications, such as infective scleritis or endophthalmitis. Surgical debridement of infected tissue may reduce the bacterial load and also improve antibiotic penetration into deep stroma, where organisms may have been seeded into a surgical wound. While mycobacterial ocular infection is rare, it must be kept in mind by all ophthalmic health providers when evaluating any atypical post-laser or post-surgical infection. NTM are a particular diagnostic and treatment challenge compared to other microbes due to delays in pathogen identification, multiple antibiotic resistances and a higher likelihood to require surgical intervention. Therefore, maintaining a high level of suspicion in unusual cases, obtaining early, accurate microbial diagnosis, with aggressive and extended antimicrobial treatment and early surgical intervention are key to minimising morbidity and maximizing visual outcome. ▀ Fig 2. Apparent early control of keratitis after three months of treatment. Note the quiescent eye but suspicious white deposits in stroma. Ciprofloxacin was stopped at this stage Fig 4b. Anterior segment optical coherence tomography (AS-OCT) image through infected graft, demonstrating fluid in the graft-host interface References 1. Kheir WJ, Sheheitli H, Abdul Fattah M, Hamam RN. Nontuberculous mycobacterial ocular infections: A Systematic Review of the Literature. Biomed Res Int. 2015;2015:164989. 2. Freitas D, Alvarenga L, Sampaio J, Mannis M, Sato E, Sousa L, et al. An outbreak of Mycobacterium chelonae infection after LASIK. Ophthalmology. 2003 Feb;110(2):276-85. 3. John T1, Velotta E. Nontuberculous (atypical) mycobacterial keratitis after LASIK: current status and clinical implications. Cornea. 2005 Apr;24(3):245-55. 4. Martinez JD, Amescua G, Lozano-Cárdenas J, Suh LH. Bilateral Mycobacterium chelonae keratitis after phacoemulsification cataract surgery. Case Rep Ophthalmol Med. 2017;2017:6413160. 5. Servat JJ, Ramos-Esteban JC, Tauber S, Bia FJ. Mycobacterium chelonae-Mycobacterium abscessus complex clear corneal wound infection with recurrent hypopyon and perforation after phacoemulsification and intraocular lens implantation. J Cataract Refract Surg. 2005 Jul;31(7):1448-51. 6. Ramaswamy AA, Biswas J, Bhaskar V, Gopal L, Rajagopal Coming soon Fig 3. Appearance of the (5mm) temporal, lamellar tectonic corneal graft post-op, day 19, demonstrating white interface specks on retro-illumination, heralding the return of infection R, Madhavan HN. Postoperative Mycobacterium chelonae endophthalmitis after extracapsular cataract extraction and posterior chamber intraocular lens implantation. Ophthalmology. 2000 Jul;107(7):1283-6. 7. De la Cruz J, Behlau I, Pineda R. Atypical mycobacteria keratitis after laser in situ keratomileusis unresponsive to fourthgeneration fluoroquinolone therapy. J Cataract Refract Surg. 2007 Jul;33(7):1318-21. 8. Girgis DO, Karp CL, Miller D. Ocular infections caused by non-tuberculous mycobacteria: update on epidemiology and management. Clin Exp Ophthalmol. 2012 Jul;40(5):467-75. *Dr Lucy Lu (pictured) is a clinical research fellow and Dr Jennifer Court is a senior corneal fellow with the Department of Ophthalmology at Auckland University. Professor Charles McGhee is department head, a consultant ophthalmologist and chair of RANZCO’s Cornea Society iStent inject is intended to provide safe and effective IOP reduction by addressing OAG at the primary site of resistance to outflow iStent inject: • Re-establishes physiological outflow to significantly decrease IOP • Reduces or eliminates drug burden • Indicated with and without cataract surgery • Developed by Glaukos Corporation, the corporate founder of Micro-Invasive Glaucoma Surgery (MIGS) Toomac Ophthalmic DIVISION OF TOOMAC HOLDINGS LTD 32D Poland Road, Wairau Valley, Auckland Tel: 0508 443 534 Email: ©2018 Glaukos Corporation. Glaukos and iStent inject are registered trademarks of Glaukos Corporation. GL33071 Glaukos iStent Inject QtrPage Adv.indd 1 March 2018 16/3/18 10:28 am NEW ZEALAND OPTICS 19