Department of Ophthalmology, Univ. Hospital Carl Gustav Carus, TU Dresden, Fetscherstrasse 74, 01307, Dresden, Germany.
National Center for Tumor Diseases (NCT/UCC), German Cancer Research Center (DKFZ), Faculty of Medicine and University Hospital Carl Gustav Carus, Technische Universität Dresden, Helmholtz-Zentrum Dresden-Rossendorf (HZDR), 01307, Dresden, Germany.
Graefes Arch Clin Exp Ophthalmol. 2024 May;262(5):1633-1639. doi: 10.1007/s00417-023-06326-4. Epub 2024 Jan 12.
To compare the results of retinal venous pressure (RVP) measurement performed with contact lens dynamometry (CLD) and with the new IOPstim.
In this cross-sectional study, we included 36 patients with primary open angle glaucoma with a median age (Q25; Q75) of 74 (64; 77) years (m/f = 18/18), baseline intraocular pressure (IOP): 13.9 (12.2; 15.1) mmHg. Median mean defect: - 5.8 (- 11.9; - 2.6) db. Principle of the IOPstim: an empty balloon with a diameter of 8 mm is positioned on the eye, laterally of the limbus. Under observation of the central retinal vein (CRV), the examiner inflates the balloon. As soon as the CRV starts pulsation, the inflation is stopped and the IOP is measured, equaling the RVP at this moment. In the CLD, the pulsation of the CRV is observed with a contact lens. The RVP is calculated from the attachment force applied when pulsation appears.
Three single measurements of RVP in quick succession with both methods. The sequence of the two methods was randomized. The means of the three RVP measurements were compared.
Pressures in mmHg. RVP: IOPstim: 19.4 ± 5.4 (mean ± SD), CLD: 20.3 ± 5.9. Range of three single measurements: IOPstim: 2.9 ± 1.5, CLD: 2.2 ± 1.1. The differences were RVP - RVP = - 0.94 ± 1.15, and approximately normally distributed. Bland-Altman analysis: only one data point was 0.5 mmHg higher than the upper line of agreement. The confidence interval of this line was 0.65 mmHg. Concordance correlation coefficient according to Lin (CCC): 0.96. Intraclass correlation coefficient: both methods, 0.94.
In both methods, the range of the single measurements may be taken as a sign of good reliability, the CCC of 0.96 as a sign of a very good agreement. At the mean, the IOPstim RVP values were 1 mmHg lower than those obtained with the CLD. This difference may be due to the different directions of the prevailing force vectors induced by the instruments. The IOPstim seems applicable in glaucoma diagnostics.
比较接触镜眼压计（CLD）和新型眼压刺激仪（IOPstim）测量视网膜静脉压（RVP）的结果。
在这项横断面研究中，我们纳入了 36 名患有原发性开角型青光眼的患者，中位年龄（Q25；Q75）为 74（64；77）岁（男女比例为 18/18），基线眼压（IOP）为 13.9（12.2；15.1）mmHg。平均缺损中位数：-5.8（-11.9；-2.6）dB。眼压刺激仪的原理：一个直径为 8mm 的空气球放置在眼睛的角膜缘外侧。在观察中央视网膜静脉（CRV）的同时，检查者给气球充气。一旦 CRV 开始搏动，就停止充气并测量眼压，此时眼压等于 RVP。在 CLD 中，通过接触镜观察 CRV 的搏动。当搏动出现时，通过施加的附着力来计算 RVP。
两种方法连续快速测量三次 RVP。两种方法的顺序是随机的。比较三次 RVP 测量的平均值。
以 mmHg 为单位。RVP：眼压刺激仪：19.4±5.4（平均值±标准差），CLD：20.3±5.9。三次单测量范围：眼压刺激仪：2.9±1.5，CLD：2.2±1.1。差值为 RVP-RVP=-0.94±1.15，近似正态分布。Bland-Altman 分析：只有一个数据点比一致性上限高 0.5mmHg。该线的置信区间为 0.65mmHg。根据 Lin 的 concordance correlation coefficient（Lin 一致性相关系数）（CCC）：0.96。组内相关系数：两种方法均为 0.94。
在两种方法中，单次测量的范围可作为良好可靠性的标志，0.96 的 CCC 作为非常好的一致性的标志。平均而言，眼压刺激仪的 RVP 值比 CLD 测量值低 1mmHg。这种差异可能是由于仪器引起的主要力向量的方向不同。眼压刺激仪似乎适用于青光眼的诊断。
