眼前段光学相干断层扫描仪CASIA2测量白内障患者角膜曲率和散光的重复性和再现性

Repeatability and reproducibility of corneal curvature and astigmatism measured by optical coherence tomography CASIA2 in cataract patients

目的探讨基于扫频OCT(SS-OCT)原理的眼前段光学相干断层扫描仪CASIA2测量白内障患者角膜曲率和散光的重复性和再现性。方法选取2020年3月至7月在川北医学院附属医院眼科就诊的白内障患者91例114眼(右眼64眼,左眼50眼)进行检测。术前检查者A连续测量受检眼3次,检查者B也连续测量相同受检眼3次,记录模拟角膜陡峭曲率(K_(s))、模拟角膜平坦曲率(K_(f))、模拟角膜平均曲率(K_(m))、模拟角膜散光(J_(0)和J_(45))、角膜后表面K_(s)、角膜后表面K_(f)、角膜后表面K_(m)、角膜后表面J_(0)和J_(45)、全角膜K_(s)、全角膜K_(f)、全角膜K_(m)和全角膜J_(0)和J_(45)。通过组内标准差(S_(w))、重复性限(2.77 S_(w))、组内变异系数(CoV)、组内相关系数(ICC)来评价重复性和再现性。S_(w)、2.77S_(w)、CoV越小,ICC越接近1,说明重复性和再现性越好。结果重复性评价方面,两名检查者测得的各角膜曲率(K_(s)、K_(f)、K_(m))值和散光(J_(0)和J_(45))值的S_(w)、2.77S_(w)、CoV均较小,并且ICC均值均≥0.903,其中各角膜曲率(K s、K f、K m)值的ICC均值均≥0.993(接近于1),说明CASIA2测量白内障患者角膜曲率和散光的重复性较好。再现性评价方面,各角膜曲率(K_(s)、K_(f)、K_(m))值和散光(J_(0)和J_(45))值的S_(w)、2.77S_(w)、CoV均较小,并且ICC均值均≥0.902,其中各角膜曲率(K_(s)、K_(f)、K_(m))值的ICC均值均≥0.991(接近于1),说明CASIA2测量白内障患者角膜曲率和散光的再现性较好。结论基于SS-OCT原理的眼前段光学相干断层扫描仪CASIA2测量白内障患者角膜曲率和散光具有较好的重复性和再现性。

Objective To investigate the repeatability and reproducibility of the measurement of the corneal curvature and astigmatism by optical coherence tomography CASIA2 based on the principle of swept-source optical coherence tomography(SS-OCT)in cataract patients.Methods Totally 91 cataract patients(64 right eyes and 50 left eyes)who were admitted to the Ophthalmology Department of the Affiliated Hospital of North Sichuan Medical College from March 2020 to July 2020 were selected for detection.Examiner A continuously measured the subject’s eyes for 3 times,and examiner B also continuously measured the same subject’s eye for 3 times.The simulated steep keratometry(K_(s)),the simulated flat keratometry(K_(f)),the simulated mean keratometry(K m),the astigmatism(J_(0)and J_(45))of simulated keratometry,the posterior keratometry(K_(s),K_(f),K_(m)),the posterior corneal astigmatism(J_(0)and J_(45)),the total corneal refractive power(K_(s),K_(f),K_(m))and the total corneal astigmatism(J_(0)and J_(45))were recorded.Repeatability and reproducibility were evaluated by within-subject standard deviation(S_(W)),repeatability limit(2.77 S_(W)),intraclass coefficient of variation(CoV)and intraclass correlation(ICC).The smaller S_(W),2.77 S_(W)and CoV are,the closer ICC is to 1,indicating better repeatability and reproducibility.Results In the evaluation of repeatability,the S_(W),2.77 S_(W)and CoV values of corneal curvature(K_(s),K_(f)_(m))and astigmatism(J_(0)and J_(45))measured by the two subjects were all small,and the ICC values were all greater than 0.903,among which the ICC values of corneal curvature(K_(s),K_(f),K_(m))were all greater than 0.993(close to 1),indicating that CASIA2 had a good repeatability in the measurement of corneal curvature and astigmatism in cataract patients.In the evaluation of reproducibility,the S_(W),2.77 S_(W)and CoV of the corneal curvature(K_(s),K_(f),K_(m))values and astigmatism(J_(0)and J_(45))values were all small,and the ICC were all greater than 0.902,among which the ICC of the corneal curvature(K_(s),K_(f),K_(m))values were all greater than 0.991(close to 1),indicating that the reproducibility of CASIA2 in measuring the corneal curvature and astigmatism in cataract patients was good.Conclusion Repeatability and reproducibility are both good in the measurement of corneal curvature and astigmatism in cataract patients by optical coherence tomography CASIA2 based on SS-OCT principle.