Kaushik Sushmita, Singh Pandav Surinder, Ichhpujani Parul, Gupta Amod, Gupta Pramod
Advanced Eye Centre, Postgraduate Institute of Medical Education and Research, Chandigarh, India.
Eur J Ophthalmol. 2011 Sep-Oct;21(5):566-72. doi: 10.5301/EJO.2011.6289.
To compare retinal nerve fiber layer (RNFL) thickness and diagnostic capability of spectral-domain (CirrusTM) versus time-domain (Stratus®) optical coherence tomography (OCT).
A total of 123 eyes of 123 subjects including 68 normal, 32 glaucoma suspect, and 23 patients with glaucoma were prospectively recruited for the study. All subjects were scanned by Stratus® and CirrusTM OCT in the same session. Average and quadrant peripapillary RNFL measurements by both machines were correlated using Spearman correlation coefficient, and agreement between testing methods was analyzed by Bland-Altman plots. The area under receiver operating characteristic curves (AUC) for glaucoma diagnosis was calculated.
Average RNFL thickness were significantly thinner on the CirrusTM compared to the Stratus® OCT in normal subjects and glaucoma suspects (p<0.001), but thicker on the CirrusTM OCT in glaucoma patients, though the difference was not statistically significant (p = 0.53). There was good correlation between the measurements in all 3 groups. In normal controls, the average, superior, nasal, inferior, and temporal correlations were r = 0.668, 0.601, 0.508, 0.620, and 0.660, p<0.001, respectively. In glaucomatous eyes, the corresponding values were r = 0.560, p = 0.005; r = 0.423, p = 0.04; r = 0.117, p = 0.596; r = 0.742, p<0.001; r = 0.669, p<0.001, respectively. The 95% limits of agreement of average RNFL thickness were -30.2 to 13.8 µm. Area under receiver operating characteristic curves for diagnosing glaucoma were comparable (superior RNFL thickness by CirrusTM 0.925; average RNFL thickness by Stratus® 0.987). Highest correlated AUCs were for inferior and temporal quadrants.
Retinal nerve fiber layer measurements on the CirrusTM and Stratus® OCT correlate well but do not have clinically acceptable agreement between their measurements. The instruments may not be used interchangeably.
比较频域（CirrusTM）与时域（Stratus®）光学相干断层扫描（OCT）对视网膜神经纤维层（RNFL）厚度的测量及诊断能力。
前瞻性招募了123名受试者的123只眼睛，其中包括68名正常人、32名青光眼疑似患者和23名青光眼患者。所有受试者在同一时段接受Stratus®和CirrusTM OCT扫描。两台机器对视乳头周围RNFL的平均测量值和象限测量值采用Spearman相关系数进行相关性分析，并用Bland-Altman图分析检测方法之间的一致性。计算青光眼诊断的受试者操作特征曲线（AUC）下面积。
在正常受试者和青光眼疑似患者中，CirrusTM测量的平均RNFL厚度显著薄于Stratus® OCT（p<0.001），但在青光眼患者中，CirrusTM OCT测量的RNFL厚度更厚，尽管差异无统计学意义（p = 0.53）。所有3组测量值之间均具有良好的相关性。在正常对照组中，平均、上方、鼻侧、下方和颞侧的相关性分别为r = 0.668、0.601、0.508、0.620和0.660，p<0.001。在青光眼眼中，相应的值分别为r = 0.560，p = 0.005；r = 0.423，p = 0.04；r = 0.117，p = 0.596；r = 0.742，p<0.001；r = 0.669，p<0.001。平均RNFL厚度的95%一致性界限为-30.2至13.8 µm。诊断青光眼的受试者操作特征曲线下面积相当（CirrusTM测量上方RNFL厚度为0.925；Stratus®测量平均RNFL厚度为0.987）。相关性最高的AUC位于下方和颞侧象限。
CirrusTM和Stratus® OCT对视网膜神经纤维层的测量相关性良好，但测量值之间在临床上未达到可接受的一致性。这两种仪器不可互换使用。
