Mai T A, Reus N J, Lemij H G
Rotterdam Eye Hospital, Rotterdam, The Netherlands.
Ophthalmology. 2007 Nov;114(11):1988-93. doi: 10.1016/j.ophtha.2007.01.022. Epub 2007 Apr 24.
To compare the diagnostic accuracy of scanning laser polarimetry (SLP) parameters between images taken with enhanced corneal compensation (ECC) and those with variable corneal compensation (VCC) and to explore the effect of atypical birefringence patterns on this accuracy.
Cross-sectional observational study.
Forty-one healthy subjects and 92 patients with primary open-angle glaucoma.
Variable corneal compensation and ECC images were obtained of 1 eye per subject, selected randomly if both eyes were eligible. For both ECC and VCC, the areas under the receiver operating characteristic curves (AUROCs) and the sensitivity at a specificity of > or =95% were calculated per parameter in all eyes. The analyses were reperformed separately in eyes with and without atypical birefringence patterns (ABP) images.
The AUROCs and sensitivities at a specificity of > or =95% for various SLP parameters in all eyes and in eyes without ABP images.
The diagnostic accuracy for most standard parameters (temporal-superior-nasal-inferior-temporal [TSNIT] average, superior average, inferior average, and TSNIT standard deviation) in all eyes was statistically significantly higher with ECC than with VCC, except for the nerve fiber indicator (NFI). When only eyes without ABP were used for the analysis, the diagnostic accuracy of SLP parameters with VCC improved, and the differences in diagnostic accuracy between ECC and VCC for these parameters lost their statistical significance.
Standard SLP parameters (except for the NFI) generally had a higher diagnostic accuracy when eyes were imaged with ECC than with VCC because there were fewer ABP images with ECC than with VCC. Enhanced corneal compensation therefore may be more reliable than VCC for the detection of glaucoma. A future automated classifier, similar to the current NFI, may perform better if it is trained on data obtained with ECC. Clinically, retinal nerve fiber layer images with marked ABP, acquired with either ECC or VCC, should be viewed with caution.
比较增强角膜补偿（ECC）图像与可变角膜补偿（VCC）图像之间扫描激光偏振imetry（SLP）参数的诊断准确性，并探讨非典型双折射模式对该准确性的影响。
横断面观察性研究。
41名健康受试者和92名原发性开角型青光眼患者。
每个受试者随机选取1只眼睛获取可变角膜补偿和ECC图像，若双眼均符合条件则随机选择。对于ECC和VCC，计算所有眼睛中每个参数的受试者操作特征曲线下面积（AUROCs）以及特异性≥95%时的敏感度。在有和无非典型双折射模式（ABP）图像的眼睛中分别重新进行分析。
所有眼睛以及无非典型双折射模式（ABP）图像的眼睛中各种SLP参数在特异性≥95%时的AUROCs和敏感度。
在所有眼睛中，除神经纤维指数（NFI）外，大多数标准参数（颞上鼻下颞[TSNIT]平均值、上方平均值、下方平均值和TSNIT标准差）采用ECC时的诊断准确性在统计学上显著高于采用VCC时。当仅对无非典型双折射模式的眼睛进行分析时，采用VCC时SLP参数的诊断准确性有所提高，并且这些参数在ECC和VCC之间的诊断准确性差异失去统计学意义。
标准SLP参数（NFI除外）在采用ECC成像时通常比采用VCC成像具有更高的诊断准确性，因为与VCC相比，ECC的非典型双折射模式图像更少。因此，增强角膜补偿在青光眼检测方面可能比VCC更可靠。如果未来的自动分类器类似于当前的NFI，并且基于用ECC获得的数据进行训练，可能会表现得更好。临床上，对于通过ECC或VCC获得的具有明显非典型双折射模式的视网膜神经纤维层图像应谨慎看待。
