Non-steroidal anti-inflammatory agents for treating cystoid macular oedema following cataract surgery.

BACKGROUND: Cystoid macular oedema (CMO) is the accumulation of fluid in the central retina (the macula) due to leakage from dilated capillaries. It is the most common cause of poor visual outcome following cataract surgery. The exact cause is unclear. Acute CMO, defined as oedema of less than four months duration, often resolve spontaneously. CMO that persists for four months or more is termed chronic CMO. Different types of non-steroidal anti-inflammatory agents (NSAIDs) are used in the treatment of CMO which may be delivered topically or systemically.

OBJECTIVES: To examine the effectiveness of NSAIDs in the treatment of CMO following cataract surgery.

SEARCH METHODS: We searched CENTRAL (which contains the Cochrane Eyes and Vision Group Trials Register) (The Cochrane Library 2011, Issue 7), MEDLINE (January 1950 to August 2011), EMBASE (January 1980 to August 2011), Latin American and Caribbean Health Sciences Literature Database (LILACS) (January 1982 to August 2011), the metaRegister of Controlled Trials (mRCT) (www.controlled-trials.com) (August 2011) and ClinicalTrials.gov (www.clinicaltrials.gov) (August 2011). We searched the reference lists of identified trials. We searched conference abstracts (sessions related to cataract) in The Association for Research in Vision and Ophthalmology (ARVO) 1975 to 2011. We contacted experts in the field and NSAIDs manufacturers for details on published and unpublished trials.There were no language or date restrictions in the search for trials. The electronic databases were last searched on 5 August 2011.

SELECTION CRITERIA: We included randomised controlled trials evaluating the effects of NSAIDs in the treatment of CMO following cataract surgery.

DATA COLLECTION AND ANALYSIS: Two review authors independently extracted data. Since considerable heterogeneity was observed between studies we did not conduct meta-analyses.

MAIN RESULTS: Seven trials involving a total of 266 participants were included. Four trials studied the effects of NSAIDs in chronic CMO while the other three examined the effect of NSAIDs in acute CMO. Of the studies examining chronic CMO, one study enrolled 120 participants, but the remainder had 34 or fewer participants. Four different NSAIDs were used and administered in different ways. Indomethacin was used orally and was found to be ineffective for chronic CMO in one trial. Topical fenoprofen appeared effective but not statistically significantly so for chronic CMO in another small trial. Treatment with topical 0.5% ketorolac for chronic CMO was found to be effective in two trials. Three trials examined the effect of topical NSAIDs on acute CMO. The comparisons among these studies were of an NSAID to placebo, prednisolone or another NSAID. The study design differed between the studies in other important aspects thus they could not be combined in a meta-analysis.

AUTHORS' CONCLUSIONS: This review found two trials which showed that topical NSAID (0.5% ketorolac tromethamine ophthalmic solution) has a positive effect on chronic CMO and two trials which revealed no significant difference between comparative groups. As such, the effects of NSAIDs in acute and chronic CMO remain unclear and needs further investigation.