*Department of Ophthalmology, Necmettin Erbakan University School of Medicine, Konya, Turkey; and †Biostatistics Unit, Department of Medical Education and Informatics, Necmettin Erbakan University School of Medicine, Konya, Turkey.
Cornea. 2014 Nov;33(11):1164-7. doi: 10.1097/ICO.0000000000000249.
The aim of this study was to analyze and compare corneal thickness changes during corneal collagen cross-linking procedures performed with isoosmolar riboflavin solution with 20% dextran and without dextran in corneal ectatic diseases.
The patients in this study were analyzed in 2 groups: group 1 receiving riboflavin solution containing 20% dextran and group 2 receiving dextran-free riboflavin solution. Corneal thickness measurements were obtained with ultrasonic pachymetry at 6 different time points: preoperatively and at 0, 15, 30, 45, and 60 minutes after epithelial removal and initiation of ultraviolet A irradiation.
Twenty-seven eyes of 27 patients with progressive keratoconus were included in the study. In group 1 (n = 13), the mean preoperative thinnest pachymetric readings were 469.3 ± 8.5 μm, which decreased to 423.8 ± 8.9 μm after deepithelization and further decreased to 385.9 ± 10.9 μm at 15 minutes. The corneal thickness assumed a steady course at the 30-, 45-, and 60-minute measurements (378.9 ± 9.8 μm, 384.5 ± 10.5 μm, and 396.7 ± 9.4 μm, respectively). The initial change was statistically significant (P < 0.01). In group 2 (n = 14), the corneal thickness decreased from 459.4 ± 3.8 μm to 414.7 ± 2.6 μm with deepithelization, after which it increased steadily with the initiation of the dextran-free riboflavin solution. The final measurement in group 2 was 474.1 ± 9.4 μm; the increase at each time point was statistically significant when compared with the previous measurement (P < 0.01).
Using isoosmolar riboflavin solution without dextran causes a steady increase in the corneal thickness during the cross-linking procedure, as opposed to riboflavin with dextran. This result might be beneficial in broadening the spectrum of cross-linking indications in patients with thin corneas.
本研究旨在分析和比较在角膜扩张性疾病中使用等渗核黄素溶液进行角膜胶原交联（CXL）手术时，含 20%葡聚糖与不含葡聚糖的核黄素溶液对角膜厚度变化的影响。
本研究将患者分为两组：组 1 接受含 20%葡聚糖的核黄素溶液，组 2 接受不含葡聚糖的核黄素溶液。使用超声角膜测厚仪在 6 个不同时间点（术前和上皮去除及紫外线 A 照射开始后 0、15、30、45 和 60 分钟）测量角膜厚度。
本研究共纳入 27 例进展性圆锥角膜患者的 27 只眼。在组 1（n = 13）中，平均术前最薄的角膜测厚读数为 469.3 ± 8.5μm，在去上皮化后降至 423.8 ± 8.9μm，在 15 分钟时进一步降至 385.9 ± 10.9μm。角膜厚度在 30、45 和 60 分钟的测量中保持稳定（分别为 378.9 ± 9.8μm、384.5 ± 10.5μm 和 396.7 ± 9.4μm）。初始变化具有统计学意义（P < 0.01）。在组 2（n = 14）中，角膜厚度从 459.4 ± 3.8μm 在去上皮化后降至 414.7 ± 2.6μm，随后在开始使用不含葡聚糖的核黄素溶液后稳定增加。组 2 的最终测量值为 474.1 ± 9.4μm；与前一次测量相比，每个时间点的增加均具有统计学意义（P < 0.01）。
与含葡聚糖的核黄素溶液相比，使用不含葡聚糖的等渗核黄素溶液在 CXL 过程中会导致角膜厚度稳定增加。这一结果可能有益于拓宽在薄角膜患者中进行 CXL 的适应证范围。
