Prophylactic non-steroidal anti-inflammatory drugs for the prevention of macular oedema after cataract surgery.

backgroundMacular oedema (MO) is the accumulation of extracellular fluid in the central retina (the macula). It may occur after cataract surgery and may give rise to poor visual outcome, with reduced visual acuity and distortion of the central vision. MO is often self-limiting with spontaneous resolution, but a small proportion of people with chronic persistent MO may be difficult to treat. Chronic oedema may lead to the formation of cystic spaces in the retina termed 'cystoid macular oedema' (CMO). Non-steroidal anti-inflammatory drugs (NSAIDs) are commonly used in cataract surgery and may reduce the chances of developing MO.

objectivesThe aim of this review is to answer the question: is there evidence to support the prophylactic use of topical NSAIDs either in addition to, or instead of, topical steroids postoperatively to reduce the incidence of macular oedema (MO) and associated visual morbidity. SEARCH

methodsWe searched a number of electronic databases including CENTRAL, MEDLINE and Embase. Date last searched 2 September 2016. SELECTION CRITERIA: We included randomised controlled trials (RCTs) in which adult participants had undergone surgery for age-related cataract. We included participants irrespective of their baseline risk of MO, in particular we included people with diabetes and uveitis. We included trials of preoperative and/or postoperative topical NSAIDs in conjunction with postoperative topical steroids. The comparator was postoperative topical steroids alone. A secondary comparison was preoperative and/or postoperative topical NSAIDs alone versus postoperative topical steroids alone. DATA COLLECTION AND ANALYSIS: Two review authors independently selected studies for inclusion, assessed risk of bias and extracted data using standard methods expected by Cochrane. We pooled data using a random-effects model. We graded the certainty of the evidence using GRADE and considered the following: risk of bias of included studies, precision of the effect estimate, consistency of effects between studies, directness of the outcome measure and publication bias. MAIN

resultsWe identified 34 studies that were conducted in the Americas, Europe, the Eastern Mediterranean region and South-East Asia. Over 5000 people were randomised in these trials. The majority of studies enrolled one eye per participant; a small subset (4 trials) enrolled a proportion of people with bilateral surgery. Twenty-eight studies compared NSAIDs plus steroids with steroids alone. Six studies compared NSAIDs with steroids. A variety of NSAIDs were used, including ketorolac, diclofenac, nepafenac, indomethacin, bromfenac, flurbiprofen and pranopfen. Follow-up ranged from one to 12 months. In general, the studies were poorly reported. We did not judge any of the studies at low risk of bias in all domains. Six studies were funded by industry, seven studies were funded from non-industry sources, and the rest of the studies did not report the source of funding.There was low-certainty evidence that people receiving topical NSAIDs in combination with steroids may have a lower risk of poor vision due to MO at three months after cataract surgery compared with people receiving steroids alone (risk ratio (RR) 0.41, 95% confidence interval (CI) 0.23 to 0.76; eyes = 1360; studies = 5; I AUTHORS'

conclusionsUsing topical NSAIDs may reduce the risk of developing macular oedema after cataract surgery, although it is possible that current estimates as to the size of this reduction are exaggerated. It is unclear the extent to which this reduction has an impact on the visual function and quality of life of patients. There is little evidence to suggest any important effect on vision after surgery. The value of adding topical NSAIDs to steroids, or using them as an alternative to topical steroids, with a view to reducing the risk of poor visual outcome after cataract surgery is therefore uncertain. Future trials should address the remaining clinical uncertainty of whether prophylactic topical NSAIDs are of benefit, particularly with respect to longer-term follow-up (at least to 12 months), and should be large enough to detect reduction in the risk of the outcome of most interest to patients, which is chronic macular oedema leading to visual loss.