Changes in corneal thickness following vitreous surgery

PURPOSE: We investigated changes in corneal thickness following vitreous surgery and determined whether such changes can be used to evaluate the invasiveness of a vitrectomy. PATIENTS AND METHODS: This retrospective, consecutive, comparative study examined 20 eyes that had undergone 23-gauge vitrectomy. Corneal thickness was measured prior to as well as following 1 week, 1 month, and 3 months after surgery. Measurements were performed at the center and at points 3 mm superior, inferior, nasal, and temporal to the center. RESULTS: Across the 20 cases, postoperative data showed a significant increase at 1 week after surgery at all points, but recovery to preoperative levels was evident only 1 month after surgery (P < 0.05, paired t-test test). In the rhegmatogenous retinal detachment group (n = 9), mean corneal thickness 1 week after vitrectomy showed a significant increase at all points, but had recovered to preoperative levels by 1 month. In the proliferative diabetic retinopathy group (n = 5), mean corneal thickness at 1 week after vitrectomy showed a significant increase at central, inferior, and temporal points, but had recovered to preoperative levels by 1 month. In the epiretinal membrane group (n = 6), a significant difference in thickness was apparent only at the superior point between baseline and at 1 week, but had recovered to preoperative levels by 1 month. In all groups, no significant differences in thickness were apparent at any of the measurement points between preoperative measurements and at 3 months after surgery (P < 0.05, Wilcoxon signed-rank test). CONCLUSIONS: Measurement of corneal thickness is useful for assessing the extent of surgical stress following vitrectomy.