Iridotomy to slow progression of visual field loss in angle-closure glaucoma

Citation: Le JTRouse BGazzard GIridotomy to slow progression of visual field loss in angle-closure glaucomaCochrane Database of Systematic Reviews 2018, Issue 6. Art. No.: CD012270. DOI: 10.1002/14651858.CD012270.pub2.

What was the aim of this review?
The aim of this Cochrane Review was to find out whether iridotomy compared to no iridotomy can slow progression of visual field loss in (1) people with primary angle-closure glaucoma, (2) people with primary angle closure, and (3) people who are suspected of having primary angle closure. We collected and analyzed all relevant clinical trials to answer this question and found two studies awaiting full publication of results.

Key messages
At the time of review, it is uncertain whether iridotomy can slow progression of visual field loss. When they become available, full publication of the results from the two studies may clarify the benefits of iridotomy.

What did we study in this review?
Glaucoma is a group of eye diseases that cause damage to the nerve in the eye. If untreated, glaucoma can lead to blindness. Primary angle-closure glaucoma is a type of glaucoma which happens when the drainage canals ("angles") in the eyes get blocked, like a sink with something covering the drain. This blockage may lead to increased eye pressure and hence a decrease of the total area in which objects can be seen in side vision ('visual field').

Iridotomy involves using a laser to create a hole in the eye's iris, the colorful disc around the pupil. This opening allows fluid to flow again, which helps controleye pressure and may slow progression of visual field loss.

What were the main results of this review?
At the time of conducting this review, we identified two trials with publication of the full trial results still under preparation. Both trials recruited participants from Asia. One eye of each participant received iridotomy and the other eye did not receive iridotomy. No data are available to assess the effectiveness of iridotomy on slowing progression of visual field loss. Low- to moderate-quality evidence from one trial suggests that iridotomy increases width of the drainage angle ('angle width') at 18 months post-treatment and may be associated with adverse events, such as 'spikes' of increased eye pressure at one hour post-treatment.

How up to date is the review?
We searched for studies that have been published up to 18 October 2017.