NHMRC Glaucoma Guidelines - ANZGIG

NHMRC GUIDELINES FOR THE SCREENING, PROGNOSIS, DIAGNOSIS, MANAGEMENT AND PREVENTION OF GLAUCOMA
Chapter 10 – Laser therapy and surgery
The literature indicates that one year after laser therapy, for open angle glaucoma (OAG) the
condition is successfully controlled in approximately 80% of patients (American Optometric
Association [AOA] 2002). After the first year, this rate declines by about 5−15% per year. In general,
glaucoma is successfully controlled in approximately 50% of patients five years after laser therapy
and 10–30% of patients 10 years after laser therapy (AOA 2002). When laser trabeculoplasty is
given as primary treatment, approximately 50% of patients do not require medication for one to
two years after treatment (Tuulonen, Airaksinen, Erola et al 2003). The IOP-lowering effect of laser
trabeculoplasty diminishes by approximately eight percent per year and follow-up of up to seven
years suggests that only 20% of patients manage without medication (Tuulonen et al 2003).
Repeated laser therapy has a lower success rate and a higher risk of poor outcomes than one
administration of laser therapy only (AOA 2002).
Selective laser trabeculoplasty appears to be equivalent to argon laser trabeculoplasty in lowering
IOP. Patients who previously failed to improve with argon laser trabeculoplasty may have a greater
reduction in IOP when treated with selective laser trabeculoplasty (AOA 2002). Usually, medications
should continue following laser therapy, and in only 25% of cases can it be reduced from pre-laser
levels. The risk of failure to control the progression of glaucoma with laser therapy is higher in
younger patients, when pre-treatment IOP is very high, and when glaucoma is more severe
(AOA 2002).
Evidence Statements
• Evidence strongly supports argon laser trabeculoplasty for older patients with glaucoma who are at
risk of visual loss within their lifetime, particularly when the following factors apply:
−−there is difficulty with administering eye drops
−−patients are unresponsive to medication alone, or
−−patients are poor candidates for incisional surgery.
• Expert/consensus opinion suggests that patients undergoing laser therapy require continual
comprehensive glaucoma monitoring due to the diminishing treatment benefit over time.
Communication with patients
Irrespective of the way in which glaucoma is managed, health care providers should continue to
educate patients about the need for monitoring. They should ensure that patients understand
that even if successful, laser therapy does not equate to a cure.
point of note
Expert opinion indicates that the high success rates of argon laser trabeculoplasty obtained in clinical
trials may not be easily achieved in clinical practice.
point of note
After a patient undergoes laser therapy, the health care provider responsible for long-term
monitoring should be clearly identified, particularly when medication is no longer required.
142 National Health and Medical Research Council