Department of Ophthalmology; Beijing Key Laboratory of Restoration of Damaged Ocular Nerve, Peking University Third Hospital, Beijing 100191, China.
Department of Ophthalmology, Qingdao Sanatorium of Shandong Province, Qingdao, Shandong 266071, China.
Chin Med J (Engl). 2018 Oct 20;131(20):2439-2446. doi: 10.4103/0366-6999.243564.
Standard automated perimetry does not sufficiently detect early open-angle glaucoma (OAG) in the clinic. New visual function tests for early glaucoma damage are therefore needed. The present study evaluated whether an isolated-check visual evoked potential (icVEP) could be used to detect visual function abnormalities in early-stage OAG and to explore potential related factors.
This was a cross-sectional study. Thirty-seven OAG patients with early-stage visual field loss (mean deviation ≥ -6.00 dB) detected by the Humphrey Field Analyzer (30-2 SITA program) and 26 controls were included in this study. Optical coherence tomography (OCT) was used to detect retinal nerve fiber layer (RNFL) defects. The icVEP preferentially evaluates the magnocellular-ON pathway. VEPs were recorded and signal-to-noise ratios (SNRs) were derived based on multivariate analysis. Eyes that yielded an SNR ≤1 were considered abnormal. Receiver operating characteristic (ROC) curve analysis was used to estimate the accuracy of group classification. Correlations between SNRs and related factors were analyzed.
Based on an SNR criterion of 1, the icVEP had a sensitivity of 62.2% and a specificity of 92.3% for diagnosing early-stage OAG with 74.6% classification accuracy. The ROC curve analysis, however, suggested that an SNR criterion of 0.93 would produce the highest classification accuracy (77.3%). Both RNFL thinning in the temporal superior quadrant on OCT and number of abnormal test points in the central 11° visual field (pattern deviation, P < 0.5%) significantly correlated with the SNR (P < 0.05).
The icVEP detected visual function abnormalities in approximately 3/5 of eyes with early-stage OAG with greater than 90% specificity. SNR correlated with both a decrease in RNFL thickness and severity of central visual field loss.
标准的自动化视野检查在临床上不能充分检测到早期开角型青光眼（OAG）。因此，需要新的视觉功能测试来早期检测青光眼损伤。本研究评估孤立检查视觉诱发电位（icVEP）是否可用于检测早期 OAG 中的视觉功能异常，并探讨潜在的相关因素。
这是一项横断面研究。纳入了 37 例由 Humphrey 视野分析仪（30-2 SITA 程序）检测到早期视野丧失（平均偏差≥-6.00 dB）的 OAG 患者和 26 例对照者。光学相干断层扫描（OCT）用于检测视网膜神经纤维层（RNFL）缺陷。icVEP 优先评估大细胞 ON 通路。记录 VEP，并基于多元分析得出信噪比（SNR）。SNR≤1 的眼被认为异常。使用受试者工作特征（ROC）曲线分析来估计组分类的准确性。分析 SNR 与相关因素之间的相关性。
根据 SNR 标准为 1，icVEP 对早期 OAG 的诊断敏感性为 62.2%，特异性为 92.3%，分类准确率为 74.6%。然而，ROC 曲线分析表明，SNR 标准为 0.93 时会产生最高的分类准确率（77.3%）。OCT 颞上象限的 RNFL 变薄和中央 11°视野（模式偏差，P<0.5%）中异常测试点的数量均与 SNR 显著相关（P<0.05）。
icVEP 在大约 3/5 的早期 OAG 眼中检测到视觉功能异常，特异性大于 90%。SNR 与 RNFL 厚度减少和中央视野丧失严重程度相关。
