J Refract Surg. 2014 Jun;30(6):366-72. doi: 10.3928/1081597X-20140523-01.
To report a novel method of contact lens-assisted corneal cross-linking (CACXL) in eyes with thin corneas.
Patients diagnosed as having progressive keratectasia with a minimum corneal thickness less than 400 and greater than 350 μm after epithelial abrasion were included. After epithelial abrasion, the iso-osmolar riboflavin 0.1% in dextran was applied every 3 minutes for 30 minutes. An ultraviolet barrier-free soft contact lens (0.09-mm thickness, 14-mm diameter) soaked in iso-osmolar riboflavin 0.1% for 30 minutes was placed on the cornea. Once the minimum corneal thickness value was confirmed to be greater than 400 μm, the ultraviolet-A irradiance was started along with instillation of iso-osmolar riboflavin 0.1% in the pre-corneal and pre-contact lens region. Intraoperative minimum corneal thickness changes were recorded with ultrasound pachymetry and optical coherence tomography. Postoperative visual acuity, corneal topography (Orbscan; Bausch & Lomb, Rochester, NY), endothelial cell loss (EM-3000; Tomey, Nagoya, Japan), and stromal demarcation line (Visante; Carl Zeiss Meditec, Jena, Germany) were measured.
Fourteen eyes underwent the procedure. Mean preoperative minimum corneal thickness after epithelial abrasion was 377.2 ± 14.5 μm (range: 350 to 398 μm). There was a significant difference in minimum functional corneal thickness (Friedman test, P = .000) intraoperatively, before epithelial abrasion, after epithelial abrasion, and with contact lens and riboflavin film. Mean minimum functional corneal thickness after the contact lens was 485.1 ± 15.8 μm (range: 458 to 511 μm). Mean absolute increase in the minimum corneal thickness along with the contact lens and pre-corneal riboflavin film was 107.9 ± 9.4 μm (range: 90 to 124 μm). Mean depth of stromal demarcation line was 252.9 ± 40.8 μm (range: 208 to 360 μm). There was no significant endothelial loss (P = .063) and the corneal topography was stable at the last follow-up (P = .505).
CACXL technique was effective and safe in performing cross-linking in corneas less than 400 μm after epithelial abrasion and appeared effective based on stromal demarcation line depth.
报告一种新的接触镜辅助角膜交联（CACXL）方法，用于治疗角膜变薄的患者。
纳入上皮刮除术后角膜最小厚度小于 400μm 但大于 350μm 的进行性圆锥角膜患者。上皮刮除后，每 3 分钟应用等渗核糖核酸 0.1% 葡聚糖共 30 分钟。将浸泡在等渗核糖核酸 0.1% 中的紫外线无阻挡软性接触镜（厚度 0.09mm，直径 14mm）置于角膜上。一旦确认角膜最小厚度值大于 400μm，即可开始紫外线-A 辐照，并在前角膜和接触镜区域滴注等渗核糖核酸 0.1%。术中通过超声角膜测厚仪和光学相干断层扫描记录角膜最小厚度变化。术后测量视力、角膜地形图（Orbscan；Bausch & Lomb，罗彻斯特，NY）、内皮细胞丢失（EM-3000；Tomey，名古屋，日本）和基质分界线（Visante；卡尔蔡司 Meditec，耶拿，德国）。
14 只眼接受了该手术。上皮刮除术后平均角膜最小厚度为 377.2±14.5μm（范围：350398μm）。术中术前、上皮刮除后、接触镜和核糖核酸膜时最小功能角膜厚度有显著差异（Friedman 检验，P=0.000）。接触镜后平均最小功能角膜厚度为 485.1±15.8μm（范围：458511μm）。接触镜和前角膜核糖核酸膜时角膜最小厚度平均绝对增加 107.9±9.4μm（范围：90124μm）。基质分界线平均深度为 252.9±40.8μm（范围：208360μm）。内皮细胞丢失无显著差异（P=0.063），角膜地形图在最后随访时稳定（P=0.505）。
上皮刮除术后角膜厚度小于 400μm 时，CACXL 技术可有效、安全地进行交联，且基于基质分界线深度，该技术似乎有效。
