FD-OCT、Visante OCT及A超角膜测厚仪测量人中央角膜厚度的比较

目的比较FD-OCT、Visante OCT及A超角膜测厚仪测量人中央角膜厚度的差异,为临床检查提供参考。方法 选取健康志愿者27人(54眼),依次用FD-OCT、VisanteOCT及A超角膜测厚仪测量双眼中央角膜厚度,三种仪器均测量3次,取其平均值,对所得数据进行统计学分析。结果 54眼志愿者中央角膜厚度测量结果:FD-OCT测量值为(530.74±31.74)μm,Visante OCT为(554.06±33.32)μm,A超为(531.61±31.76)μm。三种测量方法结果差异有统计学意义(F=9.053,P<0.01)。两两比较显示:FD-OCT测量结果与A超相比,差异无统计学意义(P>0.05);Visante OCT与A超相比,差异有统计学意义(P<0.05);Visante OCT和FD-OCT相比,差异也有统计学意义(P<0.05),但两种测量结果高度相关(r=0.949),前者所测中央角膜厚度较后者厚(23.32±10.46)μm,两者差值的95%可信区间为20.46～26.17μm。结论 A超作为目前角膜厚度测量的金标准,随着检查舒适度、检查速度等要求的提高,使用渐显局限。新的角膜测厚仪的出现,有望改善这些问题,但是诊断分析时需注意其可能带来的测量结果偏差。

使用Visante OCT评估准分子激光LASIK手术角膜瓣厚度及角膜基质切削深度

目的测量准分子激光LASIK手术术后,角膜瓣厚度以及角膜基质切削深度,评价准分子手术的安全性、可预测性。方法使用Visante OCT测量LASIK近视术后患者的角膜瓣厚度,术前术后中央角膜厚度。对照术前设定值进行统计学分析。结果准分子LASIK手术术后角膜瓣厚度值和残留基质层厚度值与术前设定值经统计学分析无差异(P>0.05)。结论使用角膜板层刀制作角膜瓣厚度以及准分子激光机切削角膜基质深度安全,可预测。

Optovue iVue OCT测量角膜厚度的可重复性及其与Pentacam、Visante OCT的一致性研究

背景 角膜厚度测量对角膜屈光手术和眼病的诊断具有重要意义,Optovue iVue OCT是测量角膜厚度的新型频域OCT,了解其测量角膜厚度的可重复性及其与目前常用的Pentacam、Visante OCT的一致性,有助于对其临床应用价值进行客观评价. 目的 评价Optovue iVue OCT测量角膜厚度的可重复性,分析其与Pentacam三维眼前节分析诊断系统、Visante OCT测量角膜厚度的一致性. 方法 选取45例拟行角膜屈光手术的近视患者的右眼,分别用Optovue iVue OCT、Pentacam、Visante OCT对角膜最薄点、中央点和距角膜中央1 mm的3：00、6：00、9：00、12：00位进行厚度测量,采用组内相关系数（ICC）对Optovue iVue OCT 3次测量的可重复性进行分析,采用Bland-Altman一致性检验分析Optovue iVue OCT与Pentacam、Visante OCT的一致性;对Optovue iVue OCT所测8个象限的平均角膜厚度进行分析. 结果 Optovue iVue OCT在6个点的3次角膜厚度测量结果差异无统计学意义（P=0.546）,角膜最薄点、中央点、距角膜中央半径1 mm的3：00、6：00、9：00、12：00位ICC分别为99.92％、99.99％、99.96％、99.99％、99.99％和99.97％;Optovue iVue OCT、Visante OCT、Pentacam在6个点所测的角膜厚度值组间比较差异均有统计学意义（P=0.000、0.001、0.000、0.003、0.002、0.000）.两两比较结果显示,Optovue iVue OCT所测6个点角膜厚度值比Pentacarm测量值平均低24.20 μm,差异均有统计学意义（P=0.000、0.001、0.000、0.003、0.004、0.000）,一致性检验差异较大.Optovue iVue OCT测量的角膜厚度与Visante OCT比较,除12：00位差异有统计学意义（P=0.016）外,其余各点差异均无统计学意义（P=1.000、0.447、0.239、1.000、1.000）,一致性较好.Pentacam所测角膜厚度值比Visante OCT测量值平均高14.01 μm,除中央点差异无统计学意义（P=0.056）外,其余各点差异均有统计学意义（P=0.009、0.005、0.034、0.017、0.008）,一致性较差.Optovue iVue OCT所测8个象限平均角膜厚度颞下象限最薄者23例,占51.11％,上方和鼻上象限最厚者各21例,分别占46.66％. 结论 Optovue iVue OCT测量角膜厚度重复性好,其测量值与Visante OCT一致性好,但与Pentacam测量角膜厚度一致性差异较大,互相替代使用时应慎重.Optovue iVue OCT所测各象限平均角膜厚度大多数颞下象限最薄,鼻上、上方象限较厚.

Repeatability and agreement of two anterior segment OCT in myopic patients before implantable collamer lenses implantation

AIM: To evaluate the intra-operator repeatability of time domain and swept-source Fourier domain anterior segment optical coherence tomography(AS-OCT), namely, Visante ASOCT and Casia SS-1000 OCT, in measuring the preoperative parameters of implantable collamer lens(ICL) in myopic eyes, as well as the agreement between the two devices.METHODS: A total of 97 eyes from 49 myopes were investigated in this prospective case series study. The anterior chamber depth(ACD), angle-to-angle distance(ATA), pupil diameter(PD) and crystalline lens rise(CLR) in all subjects were measured for three times during one session by the same operator. The repeatability was evaluated using the within-subject standard deviation(Sw), repeatability limits and intraclass correlation coefficients(ICC). The agreement between the two systems was evaluated using the Bland-Altman plots and 95% limits of agreement(Lo A).RESULTS: The repeatability limits of Visante AS-OCT in measuring ACD, ATA, PD and CLR were 0.099, 0.141, 0.304, and 0.079 mm, respectively. The repeatability limits of Casia SS-1000 OCT in measuring ACD, ATA, PD, and CLR were 0.105, 0.127, 0.357, and 0.082 mm, respectively. Excellent repeatability could be attained in both devices, with the ICC>0.8 for all the measured variables. The interdevice agreement was excellent(P>0.05) for ACD and ATA, but poor(P<0.05) for PD and CLR.CONCLUSION: Good repeatability can be attained by time domain and swept-source Fourier-domain OCT for all the measured variables. Moreover, interdevice agreement analysis suggests that interchangeable measurements between two devices can be achieved for ACD and ATA, but not for PD and CLR;but the differences in measurements were not clinically significant.

Measurements of anterior segment parameters using three different non-contact optical devices in keratoconus patients

AIM:To evaluate the measurements of anterior segment parameters using three different non-contact optical devices in keratoconus patients.·METHODS:A hundred and one eyes of 55 keratoconus patients were enrolled in this study.The mean age was26.2 ±8.9 years.The inclusion criteria were keratoconus stage I to III according to the Amsler-Krumeich keratoconus classification.All the measurements were done by the same operator,under the mesopic light condition and repeated with three different optical methods;Visante,Orbscan and Pentacam.The evaluated anterior segment parameters were anterior chamber depth(ACD),central and thinnest corneal thickness(CCT and TCT) and pupil diameter(PD).·RESULTS:The mean CCT measured by Visante,Orbscan and Pentacam were as follows:462.0 ±48.1μm,463.9±60.9μm,476.5±45.3μm,respectively(P =0.873).The mean ACD values were 3.34±0.33mm,3.26±0.33mm,3.49±0.40mm,respectively(P=0.118).The mean PD measurements were 5.11 ±1.14mm,4.80 ±0.85mm,3.80 ±1.38mm,respectively(P <0.001).The mean TCT measurements of Visante,Orbscan and Pentacam were 437.9 ±48.2μm,447.6±60.6μm and 459.9±44.0μm,respectively(P =0.214).The Visante and Orbscan measured CCT similarly,while Pentacam measured CCT thicker than the other two.The Visante measured TCT thinner than the other two devices.In ACD measurements,Orbscan was the one giving the lowest values.PD was measured differently by the devices.·CONCLUSION:Although TCT,CCT and ACD measurements acquired by Visante,Orbscan and Pentacam in keratoconus patients are similar,PDmeasurements show large differences among the devices.