摘要
目的比较准分子激光原位角膜磨镶术(LASIK)及飞秒激光制瓣准分子激光原位角膜磨镶术(FS-LASIK)术前与术后角膜形态学及生物力学的变化,评估断层扫描生物力学指数(TBI)值在术前早期圆锥角膜筛查中的应用价值。方法收集2018年5月至12月于山西省眼科医院准分子激光科行LASIK或FS-LASIK手术患者72例(117只眼)的病例资料。其中,男性34例(52只眼),女性38例(65只眼)。根据TBI<0.29及TBI≥0.29分为正常组40例(66只眼)和可疑组32例(51只眼)。收集所有患者的年龄、角膜直径,术前及术后1个月、术后3年的等效球镜屈光度、裸眼视力及最佳矫正视力。应用Pentacam眼前节分析系统测量中央角膜厚度(CCT)、角膜最薄点厚度、角膜最薄点后表面高度、角膜最大曲率(Kmax)上下方曲率不对称指数(I-S value)、前表面高度的标准偏差指数(Df)、后表面高度的标准偏差指数(Db)、厚度变化率的标准偏差指数(Dp)、最薄点厚度的标准偏差指数(Dt)、最薄点相对厚度标准偏差指数(Da)及Pentacam断层扫描综合指数(BAD-D)等指标;应用Corvis ST可视化角膜生物力学分析仪测量Pentacam随机森林指数(PRFI)、角膜第一压平时硬度参数(SP-A1)、综合半径指数(IR)、Ambrosio水平方向上相关厚度(ARTh)、角膜变形幅度比(DA ratio)、Corvis生物力学综合指数(CBI)及TBI等。各参数符合正态分布,以±s表示。两组患者年龄的比较采用χ^(2)检验;术前、术后1个月及术后3年变化的比较采用重复测量方差分析或独立样本t检验;选取术前差异有统计学意义的参数,比较分析其术前与术后3年的差值(Δ);对Δ有差异的参数进行多因素Logistics回归分析。结果可疑组患者术前、术后1个月及术后3年角膜最薄点角膜后表面高度分别为(7.74±1.65)μm、(5.19±1.68)μm及(4.67±1.73)μm,与正常组比较的差异无统计学意义(F=0.120,0.055,0.407;P>0.05)。两组患者术前角膜最薄点后表面高度均高于术后,差异有统计学意义(t=3.731,6.631,3.269,6.166;P<0.05);且两组患者术前及术后角膜后表面高度图形态均为桥型递减型或不完全桥型。两组患者术前、术后1个月及术后3年角膜最薄点后表面高度的组间比较差异均无统计学意义(F=0.120,0.055,0.407;P>0.05)。可疑组患者术前CBI、PRFI、I-Svalue、Kmax、Dp、Da及BAD-D高于正常组,差异有统计学意义(t=-2.564,-5.629,-2.352,-2.551,-3.268,-2.596,-2.124;P<0.05);ARTh低于正常组,差异有统计学意义(t=3.239,P<0.05);术前两组角膜直径、Db、Df、Dt、SPA1、IR及DA Ratio比较的差异无统计学意义(t=0.235,-0.852,-0.898,-0.968,0.427,0.571;P>0.05)。两组患者ΔPRFI、ΔI-S value、ΔKmax、ΔDp、ΔDa及ΔARTh比较的差异均无统计学意义(t=-1.778,1.054,1.407,1.599,-0.628,1.151;P>0.05)。将TBI作为因变量,PRFI、I-S value、Kmax、Dp、Da及ARTh作为协变量进行多因素Logistics回归分析,结果显示PRFI与TBI≥0.29具有相关性且有统计学意义(β=2.717,95%CI:3.104~73.784,P<0.05)。结论在角膜后表面高度图形态为不完全桥型或桥型递减型时,TBI≥0.29主要与PRFI有关。当TBI≥0.29且因PRFI导致时,TBI值对术前筛查圆锥角膜的预测作用仍有待商榷;但若因其他因素导致,则仍应警惕术后角膜扩张的风险。
Objective To evaluate the tomography biomechanical index(TBI)value in early corneal dilatation by observing the morphological and biomechanical changes of laser in situ keratomileusis(LASIK)and femtosecond laser-assisted excimer laser in situ keratomileusis(FS-LASIK).Methods 72 patients(117 eyes)who received LASIK or FS-LASIK in the Excimer Laser of Shanxi Eye Hospital from January to December 2018 and had complete clinical data and routine follow-up after surgery for 3 years were collected.According to the TBI,they were divided into two groups normal group(TBI<0.29)and suspicious group(TBI≥0.29).The patient′s age,the corneal diameter,the vision and refraction before and after surgery were collected.Preoperative and postoperative parameters,including corneal central thickness(CCT),thickness of thinnest point of cornea,surface height behind the thinnest point of cornea,maximum keratometry(Kmax),inferior-superior difference value(I-S value),deviation of front elevation difference map(Df),deviation of back elevation difference map(Db),deviation of average pachymetric progression(Dp),deviation of minimum thickness(Dt),deviation of ARTmax(Da),total deviation value(BAD-D),were measured using Pentacam anterior segment analyzer;Pentacam random forest index(PRFI),stiffness parameter(SPA1),Ambrósio′s relational thickness to the horizontal profile(ARTh),integrated radius(IR),deformation amplitude ratio(DA ratio),Corvis biomechanical index(CBI),were measured using the corneal visualization scheimpflug technology.Parameters conform to normal distribution and were expressed by±s,and compared by ANOVA andttest;the age was compared by chi-square.The preoperative parameters with statistically significant differences were selected and the D-value of preoperative and 3rd postoperative years compared(Δ).The Logistics analysis was performed if variables with statistical significance differences.Results The height of posterior corneal surface at the thinnest point in suspicious group was(7.74±1.65)μm,(5.19±1.68)μm and(4.67±1.73)μm before surgery,after surgery for 1 month and 3 years,respectively.There was no significant difference between them(F=0.120,0.055,0.407;P>0.05).The height of the corneal posterior surface of the thinnest point before surgery were higher than after surgery with statistical significance differences(t=3.731,6.631,3.269,6.166;P<0.05).There was no significant difference in the surface height after the thinnest point between the two groups before surgery,after surgery for 1 month and 3 years(F=0.120,0.055,0.407;P>0.05).Preoperative CBI,PRFI,I-S value,Kmax,Dp,Da and BAD-D in the suspicious group were higher than those of the normal group,and the difference was statistically significant(t=-2.564,-5.629,-2.352,-2.551,-3.268,-2.596,-2.124;P<0.05).ARTh was lower than normal group,and the difference was statistically significant(t=3.239,P<0.05).There was no significant difference inΔPRFI,ΔI-S value,ΔKmax,ΔDp,ΔDa andΔARTh between the two groups(t=-1.778,1.054,1.407,1.599,-0.628,1.151;P>0.05).TBI was taken as the dependent variable,and PRFI,I-S value,Dp,Da,ARTh were used as concomitant variables for multiple Logistic regression analysis.The results showed that PRFI was associated with TBI value changes(β=2.717,95%CI:3.104 to73.784,P<0.05).Conclusions When the height pattern of the posterior corneal surface was incomplete or decreased,TBI≥0.29 was mainly associated with PRFI.The predictive role of preoperative screening for keratoconus remains to be discussed if TBI≥0.29 was caused by PRFI;the risk of postoperative corneal dilation should be vigilant if TBI≥0.29 was caused by others.
作者
刘佳
贺瑞
李晓娜
Liu Jia;He Rui;Li Xiaona(the First Clinical Medical College of Shanxi Medical University,Taiyuan 030001,China;The First Affiliated Hospital of Northwestern University,Xi′an First Hospital,Shanxi Institute of Ophthalmology;Excimer Laser,Shanxi Eye Hospital,Taiyuan 030002,China;College of Biomedical Engineering Taiyuan University of Technology,Taiyuan 030024,China)
出处
《中华眼科医学杂志（电子版）》
2022年第6期341-346,共6页
Chinese Journal of Ophthalmologic Medicine(Electronic Edition)
基金
国家自然科学基金项目(12072218)
作者简介
通信作者:贺瑞,Email:he.r@163.com;刘佳,山西医科大学第一临床医学院2019级研究生.
