Visual outcomes and associated risk factors of cataract surgeries in highly myopic Taiwanese.

Aims: The purposes of this study are to describe the visual outcome of highly myopic eyes undergoing cataract surgery, to investigate associated risk factors for poor postoperative vision and to assess the postoperative complication frequency among the myopic Taiwanese population.

Methods: We conducted a retrospective, noncomparative case series study at the Department of Ophthalmology, Zhongxing Branch, Taipei City Hospital, Taiwan. High myopia was defined as axial length > or =26.0 mm. The main study outcomes were visual acuity for the initial 6-month postoperative period (including visual acuities and improvement of postoperative vision) and postoperative complications (including subsequent cataract formation and postoperative retinal detachment).

Results: Fifty-two highly myopic eyes were enrolled between January 2002 and December 2004. The mean follow-up interval was 43.3 +/- 20.2 weeks (range 25-103). Thirty-two eyes (61.5%) had good postoperative visual improvement (> or =4 lines of Snellen chart). Thirty-seven eyes (71.2%) achieved good postoperative vision (20/40 or better). Fifteen eyes (28.8%) demonstrated poor postoperative vision. Pre-existing maculopathy was an independent risk factor for failure to achieve good postoperative vision [odds ratio (OR): 6.84, 95% confidence interval (CI): 1.12-41.8] and improvement (OR: 16.1, 95% CI: 2.2-119.9). Diabetic history was considered another independent risk factor for poor postoperative vision (OR: 15.6, 95% CI: 0.97-267.6). Six eyes (11.5%) developed subsequent posterior capsular opacification requiring Nd:YAG laser capsulotomy. Two eyes (3.8%) developed retinal detachment during follow-up.

Conclusions: Most highly myopic eyes achieved good visual improvement and good postoperative visual acuity after cataract surgery. Pre-existing maculopathy was an independent risk factor of postoperative visual improvement and status. It is crucial to examine retinal status prior to cataract surgery to prevent poor vision improvement, poor postoperative vision or retinal complications.