Bazzazi Noushin, Barazandeh Behzad, Kashani Mani, Rasouli Maryam
Besat Hospital, Hamedan Medical University, Hamedan, Iran.
J Ophthalmic Vis Res. 2008 Apr;3(2):87-90.
To compare the efficacy of adding an opposite clear corneal incision (OCCI) on the steep meridian versus performing surgery on the steep meridian alone during phacoemulsification in reducing pre-existing corneal astigmatism.
This randomized clinical trial was performed on 120 eyes with corneal astigmatism of >1D undergoing phacoemulsification. Incisions were made based on the type of astigmatism as follows: superior or superior+OCCI for with-the-rule and temporal or temporal+OCCI for against-the-rule astigmatism. Patients were followed with refraction, keratometry and topography. Statistical analysis was performed using one- and two-way ANOVA and Tukey-a test.
Mean corneal astigmatism was 1.82±0.86 D in the superior+OCCI group and 1.74±0.86 D in the temporal+OCCI group preoperatively which decreased to 1.31±0.59(P=0.013) and 1.19±0.64 (P=0.009) postoperatively respectively. No significant change occurred in the amount of astigmatism in any of the two single incision groups.
Paired OCCI on the steep axis is a useful technique to correct mild to moderate pre-existing astigmatism with no need for particular skill or additional instruments.
比较在白内障超声乳化手术中，在陡峭子午线处增加一个相对的透明角膜切口（OCCI）与仅在陡峭子午线处进行手术在减少术前角膜散光方面的疗效。
对120只术前角膜散光大于1D且接受白内障超声乳化手术的眼睛进行了这项随机临床试验。根据散光类型进行切口，如下：顺规散光采用上方或上方+OCCI切口，逆规散光采用颞侧或颞侧+OCCI切口。对患者进行验光、角膜曲率测量和地形图检查随访。采用单因素和双因素方差分析以及Tukey-a检验进行统计分析。
术前，上方+OCCI组平均角膜散光为1.82±0.86 D，颞侧+OCCI组为1.74±0.86 D，术后分别降至1.31±0.59（P=0.013）和1.19±0.64（P=0.009）。两个单一切口组中任何一组的散光量均未发生显著变化。
在陡峭轴线上进行配对OCCI是一种纠正轻度至中度术前散光的有用技术，无需特殊技能或额外器械。
