Choudhari Nikhil S, Chanda Sanjay, Khanna Rohit, Senthil Sirisha, Garudadri Chandra Sekhar
a V S T Glaucoma Centre, Kallam Anji Reddy Campus , L V Prasad Eye Institute , Hyderabad , India.
b Edward and Soona Brown Eye Centre , L V Prasad Eye Institute , Sattenapalle , India.
Ophthalmic Epidemiol. 2019 Jun;26(3):175-182. doi: 10.1080/09286586.2018.1562083. Epub 2019 Jan 8.
To critically evaluate diagnostic accuracy of the van Herick (vH) technique in detection of gonioscopically occludable angle in a rural population and to explore ways to improve accuracy of the technique Methods: The study cohort was formed by two-stage cluster random sampling. Peripheral anterior chamber depth grading was performed, using both traditional and modified (photographic comparison) vH techniques, under dark adapted and standard lighting conditions by a comprehensive ophthalmologist masked to the clinical features. The cut-off criterion for vH test was 25% of peripheral corneal thickness. The reference standard was dark room 4-mirror indentation gonioscopy performed by an experienced glaucoma specialist. This study adhered to the STARD guidelines for reporting diagnostic accuracy studies.
We studied 111 eyes of 111 participants. The median age was 62 years. The angle was occludable by gonioscopy in 69 (62%) eyes; 58 eyes were primary angle closure suspects and 11 were primary angle closure patients. The likelihood ratio (95% confidence interval (CI)) of the positive (LR+) and negative (LR‒) result by the traditional vH technique was 5.17 (2.43, 11) and 0.30 (0.20, 0.46), respectively. The LR+ by reducing and LR‒ by elevating the cut-off grade of the traditional vH technique were 9.4 (2.3, 37.4) and 0.08 (0.02, 0.31), respectively. The area under receiver operating characteristic curve did not differ significantly by photographic comparison or lighting condition (p = 0.13).
vH grading can be considered as a triage test before gonioscopy. The value of the vH technique to the diagnostic strategy is discussed.
严格评估范赫里克（vH）技术在农村人群中检测前房角镜可关闭房角的诊断准确性，并探索提高该技术准确性的方法。方法：通过两阶段整群随机抽样形成研究队列。由一位对临床特征不知情的综合眼科医生，在暗适应和标准照明条件下，使用传统和改良（照片比较）vH技术进行周边前房深度分级。vH测试的截断标准为周边角膜厚度的25%。参考标准是由一位经验丰富的青光眼专家进行暗室四镜前房角镜检查。本研究遵循诊断准确性研究报告的STARD指南。
我们研究了111名参与者的111只眼。中位年龄为62岁。前房角镜检查显示69只眼（62%）的房角可关闭；58只眼为原发性房角关闭疑似病例，11只眼为原发性房角关闭患者。传统vH技术阳性（LR+）和阴性（LR‒）结果的似然比（95%置信区间（CI））分别为5.17（2.43，11）和0.30（0.20，0.46）。通过降低传统vH技术的截断等级得到的LR+和通过提高截断等级得到的LR‒分别为9.4（2.3，37.4）和0.08（0.02，0.31）。通过照片比较或照明条件，受试者操作特征曲线下面积无显著差异（p = 0.13）。
vH分级可被视为前房角镜检查前的分诊测试。讨论了vH技术对诊断策略的价值。
