白内障超声乳化术后角膜厚度变化与术源性散光的相关性

The Relationship between Corneal Thickness and Surgically Induced Astigmatism after Phacoemulsification

目的:探究透明角膜切口白内障超声乳化术后角膜厚度变化与术源性散光(SIA)的相关性。方法:回顾性系列病例研究。连续性纳入2021年9月至2022年3月于西安市第一医院眼科日间手术中心所有行透明角膜切口超声乳化白内障摘除术联合人工晶状体(IOL)植入术患者69例(69眼)。按照患者首次接受手术时的术眼分为右眼组和左眼组,观察并记录术前及术后3个月的中央角膜厚度和5 mm范围上、下、鼻、颞四个方位的角膜平均厚度及变化;通过矢量分析法,分别计算模拟角膜曲率(SimK)及前、后表面3 mm SIA,分析角膜厚度变化对SIA的影响。采用独立样本t检验以及偏相关分析对数据进行分析。结果:术前及术后3个月双眼之间各象限角膜厚度及变化差异均无统计学意义(均P>0.05)。2组之间SimK-YSIA、角膜前表面-YSIA差异有统计学意义(t=2.47,P=0.016;t=3.25,P=0.002),而后表面SIA差异无统计学意义(P>0.05)。右眼中央及各象限角膜厚度变化与后表面SIA呈正相关(r=0.39~0.49,均P<0.05),其余均无相关性(P>0.05)。左眼上方角膜厚度变化与SimK、前表面及后表面YSIA均呈负相关(r=-0.50,P=0.005;r=-0.53,P=0.002;r=-0.55,P=0.001),除上方厚度变化外,其他角膜厚度变化与SimK-XSIA呈正相关(r=0.37,P=0.040;r=0.46,P=0.010;r=0.44,P=0.013),鼻、颞侧厚度变化与前表面YSIA呈负相关(r=-0.46,P=0.009;r=-0.38,P=0.036)。结论:白内障术后3个月角膜厚度恢复至术前,角膜厚度变化与SIA存在相关性,左眼角膜厚度变化的增加可导致SIA更向顺时针方向旋转。

Objective:To investigate the relationship between corneal thickness and surgically induced astigmatism(SIA)after clear corneal incision in phacoemulsification.Methods:This was a retrospective case series study.A total of 69 patients(69 eyes)who underwent phacoemulsification cataract extraction combined with intraocular lens implantation at Xi'an No.1 Hospital's day surgery center from September 2021 to March 2022 were included in this study.Participants were divided into a right eye group and a left eye group based on their first surgery.Central corneal thickness,average corneal thickness,and alternations of the average corneal thickness in upper,lower,nasal,and temporal directions within the 5 mm were observed and recorded pre-and postoperative 3 months.Simulate keratometric power(SimK)and 3 mm SIA of the anterior and posterior surfaces were calculated to analyze the influence of corneal thickness changes on SIA by using vector analysis method.Data analysis was conducted using independent sample t-test and partial correlation analysis.Results:There was no significant difference in corneal thickness and alternations in each quadrant between eyes pre-and postoperative 3 months(P>0.05).SimK-YSIA and corneal anterior surface YSIA had statistically difference between two groups(t=2.47,P=0.016;t=3.25,P=0.002),but no difference in SIA of corneal posterior surface(P>0.05).The changes in corneal thickness in the center and various quadrants of the right eye were significantly positively correlated with the posterior surface SIA(r=0.39-0.49,all P<0.05),while the rest were not correlated(P>0.05).The alternations of corneal thickness above the left eye were negatively correlated with SimK,anterior and posterior surface YSIA(r=-0.50,P=0.005;r=-0.53,P=0.002;r=-0.55,P=0.001).Except for the alternation of upper corneal thickness,other alternations of corneal thickness were positively correlated with SimK-XSIA(r=0.37,P=0.040;r=0.46,P=0.010;r=0.44,P=0.013),while the alternations of nasal and temporal thickness were negatively correlated with YSIA of the anterior surface(r=-0.46,P=0.009;r=-0.38,P=0.036).Conclusions:Three months after cataract surgery,the corneal thickness returned to the preoperative level.There is a correlation between alternations of corneal thickness and SIA.The increase in corneal thickness of the left eye can cause SIA to rotate more clockwise.