Abstract
Purpose::
Intra- and extra-capsular cataract surgery has been shown to exacerbate existing diabetic retinopathy (DR). Modern phacoemulsification (phaco) cataract surgery is considered less destructive to ocular structures than these earlier techniques. It remains unclear, however, whether phaco surgery also exacerbates DR. In this study, we aimed to assess DR progression in patients aged 65+ years who had undergone phaco cataract surgery at Westemad Hospital, Sydney, from 2004-6.
Methods::
Over the period, 139 cataract surgical patients with diabetes were recruited and followed for at least 6 months postoperatively. Digital retinal photography was performed after dilatation pre- and at 1, 6, 12 and 24 months postoperatively. DR was graded using the ETDRS classification system. Preoperative and 1-month postoperative photos (baseline) were compared to 6- and 12-month photos. Side-by-side grading was conducted to confirm DR status change over time. Progression was defined if DR level was one or more steps severer at follow-up, including progression from none to minimal DR. Odds ratio (OR) and 95% confidence intervals (CI) were assessed after adjusting for baseline age, glucose levels, sex and diabetic duration.
Results::
Of those recruited diabetic patients with gradable photographs, 164 eyes were non-phakic and 86 were phakic at baseline. DR was detected at baseline in 65.2% of the non-phakic and 54.7% of the phakic eyes. The corresponding proportions were 67.5% vs 56.2%, and 63.7% vs 57.5%, respectively, for non-phakic and phakic eyes at 6- and 12-month visits. Non-phakic eyes had non-significantly higher odds of having DR (baseline: OR 1.6, CI 0.95-2.7; 6-month: OR 2.0, CI 1.2-3.3 and 12-month: OR 1.5, CI 0.86-2.5). Of those followed for 6 months or longer, the DR progression rate was 14.2% in non-phakic and 10.8% in phakic eyes, OR 1.9, CI 0.96-3.9 for the progression within 6-12 months. Among 81 of 93 patients with monocular surgery who had complete data, paired comparison analysis confirmed that the proportion with DR progression was higher in non-phakic than phakic eyes of the same subjects within 6-12 months after surgery (27.2% vs 18.5%, OR 1.9 CI 0.9-4.0).
Conclusions::
We document that phaco cataract surgery may still exacerbate DR progression in diabetic patients aged 65+ years, although the extent of such worsening seems to be much less than that documented with older surgical techniques.
Keywords: diabetic retinopathy • clinical (human) or epidemiologic studies: risk factor assessment • clinical (human) or epidemiologic studies: outcomes/complications