Xu Chen1, Yinghong Ji, Yi Lu. 1. Department of Ophthalmology, Zhongshan Hospital of Fudan University, Shanghai, China.
Abstract
PURPOSE: To compare thermal and mechanical clear corneal incision (CCI) injuries after conventional and torsional phacoemulsification. DESIGN: A prospective, randomized clinical study. METHODS: A total of 80 eyes were evaluated for the profile of the incision at 1 day and 3 months postoperatively. The wound architecture was recorded with anterior segment optical coherence tomography (AS-OCT). The incisional thickness increased by thermal injury, Descemet's membrane detachment (DMD) caused by mechanical injury, the presence of endothelial gaping, loss of coaptation, and wound retraction of the conventional phaco group and the torsional phaco group were compared. RESULTS: The corneal thickness at the incision site of the torsional ultrasound group was significantly lower than the conventional group compared to at the first postoperative visit (1187.55 ± 75.66, 1233.62 ± 85.87, P = .013). However, this thickness was similar between the two groups at 3 months postoperatively. The central endothelial cell loss was significantly lower in the torsional ultrasound group after 3 months (417 ± 143, 322 ± 130, P = .003). There was a positive correlation between cumulated dissipated energy (CDE) and the incisional corneal thickness change that was observed by AS-OCT. Other OCT outcome parameters (such as endothelial gap, DMD, epithelial gap, and uncoaptation) that may be caused by mechanical injury did not differ significantly between the groups on postoperative day one or after 3 months. CONCLUSIONS: The torsional ultrasound mode may provide a lower level of phacoemulsification time and energy and induce less incisional corneal thickness caused by thermal injury in the early postoperative period. The long-term wound healing appeared the same in both ultrasound mode groups.
RCT Entities:
PURPOSE: To compare thermal and mechanical clear corneal incision (CCI) injuries after conventional and torsional phacoemulsification. DESIGN: A prospective, randomized clinical study. METHODS: A total of 80 eyes were evaluated for the profile of the incision at 1 day and 3 months postoperatively. The wound architecture was recorded with anterior segment optical coherence tomography (AS-OCT). The incisional thickness increased by thermal injury, Descemet's membrane detachment (DMD) caused by mechanical injury, the presence of endothelial gaping, loss of coaptation, and wound retraction of the conventional phaco group and the torsional phaco group were compared. RESULTS: The corneal thickness at the incision site of the torsional ultrasound group was significantly lower than the conventional group compared to at the first postoperative visit (1187.55 ± 75.66, 1233.62 ± 85.87, P = .013). However, this thickness was similar between the two groups at 3 months postoperatively. The central endothelial cell loss was significantly lower in the torsional ultrasound group after 3 months (417 ± 143, 322 ± 130, P = .003). There was a positive correlation between cumulated dissipated energy (CDE) and the incisional corneal thickness change that was observed by AS-OCT. Other OCT outcome parameters (such as endothelial gap, DMD, epithelial gap, and uncoaptation) that may be caused by mechanical injury did not differ significantly between the groups on postoperative day one or after 3 months. CONCLUSIONS: The torsional ultrasound mode may provide a lower level of phacoemulsification time and energy and induce less incisional corneal thickness caused by thermal injury in the early postoperative period. The long-term wound healing appeared the same in both ultrasound mode groups.