Authors: Lin Zhibo, Chen Ding, Feng Xiaofen, Huang Fang, Wang Qinmei
To evaluate and compare the subjective and objective visual quality of YAG laser posterior capsulotomy.
A series of case observation study was designed.Twenty-eight patients (38 eyes) underwent Nd: YAG laser posterior capsulotomy in the Eye Hospital of Wenzhou Medical University were retrospectively collected from 2015 to 2016.Patients were divided into circular capsulotomy group (20 patients 23 eyes) and cruciate capsulotomy group (12 patients 15 eyes) based on the capsulotomy technique (round incision of posterior capsule or cross incision of posterior capsule). The uncorrected visual acuity (UCVA) and best corrected visual acuity (BCVA) were examined before and 2 weeks after operation, the intraocular pressure was also measured before operation, 1 hour after operation and 2 weeks after operation.The Strehl ratio (SR), modulation transfer function (MTF) cut-off, objective scatter index (OSI), OQAS values (OVs) were analyzed by Two-channel visual quality analysis system OQAS Ⅱ at 1 h and 2 weeks after operation.The changes of intraocular scattering and visual quality at 1 h and 2 weeks after operation with different posterior capsulotomy methods were compared and analyzed.
At 2 weeks after operation, the UCVA was 0.18±0.15 and 0.16±0.14, and the BCVA was 0.10±0.10 and 0.10±0.11, respectively in the circular capsulotomy group and cruciate capsulotomy group, which was higher than those before operation (all at P<0.05), but there was no significant difference in UCVA and BCVA between the two groups (all at P>0.05). There was no significant difference in intraocular pressure between the two groups at 1 hour and 2 weeks after operation (both at P>0.05). In the circular capsulotomy group, the incidence of black shadow drift was 39.1% and 30.4% respectively at 1 hour and 2 weeks after operation, which was higher than that in the cruciate capsulotomy group (6.7% and 6.7%), with no significant differences between the two groups (P=0.065, 0.177). No significant difference were found in the incidence of black shadow drift before eyes between the two groups (P>0.05), and there was no significant differences in the OQAS parameters OSI, MTF, SR, OV100%, OV20% and OV9% between the two groups (all at P>0.05).
After Nd: YAG laser capsulotomy, the incidence of black shadow drift in the cruciate capsulotomy group is lower than that in the circular capsulotomy group.There is no significant difference in the visual acuity, intraocular pressure, intraocular scattering and visual quality parameters between circular posterior capsulotomy and cross posterior capsulotomy.