Abstract
Abstract: :
Purpose: To evaluate the effect of uncomplicated standard small–incisional cataract surgery on central retinal thickness and on the development of cystoid macular edema. Methods: In a prospective clinical observational study 128 consecutive eyes (117 patients) were assessed preoperatively, one day, one week and four weeks postoperatively by visual acuity measurement, ophthalmoscopy and Optical Coherence Tomography (OCT) (Stratus OCT, Carl Zeiss Meditec). Eyes showing macular edema preoperatively due to diabetic retinopathy, exudative age–related macular degenartion were not included in the study. All eyes underwent uncomplicated small incisional phacoemusification and endocapsular implantation of an acrylic posterior chamber lens under topical anesthesia. Thirty eyes (23,9%) belonged to patients suffering from diabetes mellitus, thirty eyes (23.9%) showed signs of non–exudative age–related macular degeneration. Mean patient age was 72.4 ± 8.7 years. Mean preoperative visual acuity was 0.41 ± 0.15. Mean time of surgery was 11.6 ± 6.3 minutes. Mean foveal minimum retinal thickness (minRT) was 184 ± 30 µm (median, 178 µm; min – max, 132 – 308 µm), mean foveal retinal thickness (circle of 0.5 mm radius around to center of the macula) (fovRT) was 265 ± 34 µm. Results: Eight eyes of seven patients (6.25%) developed cystoid macular edema during follow–up. Four (50%) of these eyes belonged to diabetic subjects. FoMi was 186 ± 34 µm (median, 181 µm; min – max, 123 – 353 µm) at one day postoperatively (p=0.495), and increased significantly to 189 ± 39 µm (median, 182 µm; min – max, 132 – 447 µm) at one week (p=0.003), and 204 ± 68 µm (median, 188 µm; min – max, 125 – 644 µm) at four weeks postoperatively (p<0.001; Wilcoxon–test). Excluding eight eyes with CME at four weeks, these findings were nearly identical. Mean foveal retinal thickness increased to 269 ± 38 µm one day postoperatively (p=0.388), 272 ± 41 µm one week (p<0.001), and 292 ± 70 µm four weeks postoperatively (p<0.001). Four weeks postoperatively, mean visual acuity was significantly improved to 0.79 ± 0.22 (p<0.001). Conclusion: After uncomplicated standard small–incisional cataract surgery, subclinical foveal retinal thickening may occur without development of ophthalmoscopically detectable cystoid macular edema. In the present study 6.25 % "clinically significant" CME developed within 4 weeks after surgery.
Keywords: macula/fovea • cataract