Noor Ophthalmology Research Center, Noor Eye Hospital, Tehran, Iran.
Ophthalmology. 2013 Aug;120(8):1515-20. doi: 10.1016/j.ophtha.2013.01.012. Epub 2013 Apr 12.
To evaluate the long-term results of corneal collagen cross-linking (CXL) in patients with progressive keratoconus.
Prospective case series.
This study was conducted on 40 eyes of 32 patients with progressive keratoconus between 2006 and 2012.
Patients underwent CXL no later than 1 month after baseline examinations. For CXL, ultraviolet irradiation was applied for 30 minutes, during which riboflavin instillation was repeated every 3 minutes.
Patients were tested for best-corrected visual acuity (BCVA), uncorrected visual acuity (UCVA), manifest refraction spherical equivalent (MRSE), and Scheimpflug imaging from which we extracted maximum keratometry reading (max-K), average of minimum and maximum keratometry readings (mean-K), central corneal thickness (CCT), and anterior and posterior elevation at the apex at baseline, at 1, 3, 6 months after CXL, and 1, 2, 4, and 5 years later. We studied results at 5 years after CXL as well as the trend of changes over the 5-year period.
Mean UCVA was 0.67 ± 0.52 logarithm of the minimum angle of resolution (logMAR) at baseline and 0.65 ± 0.51 logMAR at 5 years after the procedure. For mean BCVA, these values were 0.31 ± 0.28 and 0.19 ± 0.20 logMAR, respectively (P = 0.016). The mean MRSE changed from -3.18±2.23 diopters (D) to -2.77 ± 2.18 D, and mean refractive cylinder error changed from -3.14 ± 2.22 to -2.49 ± 1.71 D (P = 0.089). Mean max-K and mean-K decreased by 0.16 ± 2.20 and 0.10 ± 1.69 D, respectively. The CCT increased from 483.87 ± 29.07 to 485.95 ± 28.43 μm. Mean anterior elevation at the apex changed from 13.9 2 ± 8.28 to 11.45 ± 8.18 μm (P = 0.030) and posterior elevation at this point changed from 29.54 ± 18.39 to 26.34 ± 19.59 μm. The mean-K, max-K, UCVA, and astigmatism showed no change over time during these 5 years. After the first year, BCVA, MRSE, and CCT showed no change and stabilized, whereas elevation readings continued to decrease up to 5 years after CXL.
Based on our 5-year results, treatment of progressive keratoconus with CXL can stop disease progression, without raising any concern for safety, and can eliminate the need for keratoplasty.
FINANCIAL DISCLOSURE(S): The authors have no proprietary or commercial interest in any of the materials discussed in this article.
评估角膜胶原交联（CXL）治疗进展性圆锥角膜的长期疗效。
前瞻性病例系列。
本研究纳入了 2006 年至 2012 年间的 32 例进展性圆锥角膜患者的 40 只眼。
患者在基线检查后 1 个月内接受 CXL。对于 CXL，紫外线照射 30 分钟，每隔 3 分钟重复滴注核黄素。
患者在基线、CXL 后 1、3、6 个月以及 1、2、4 和 5 年后接受最佳矫正视力（BCVA）、未矫正视力（UCVA）、角膜散光等效球镜（MRSE）以及Scheimpflug 成像检查，提取最大角膜曲率读数（max-K）、最小和最大角膜曲率读数的平均值（mean-K）、中央角膜厚度（CCT）以及顶点前、后高度。我们还研究了 CXL 后 5 年的结果以及 5 年内的变化趋势。
基线时，平均 UCVA 为 0.67 ± 0.52 对数最小分辨角视力（logMAR），CXL 后 5 年时为 0.65 ± 0.51 logMAR。平均 BCVA 分别为 0.31 ± 0.28 和 0.19 ± 0.20 logMAR（P = 0.016）。平均 MRSE 从-3.18±2.23 屈光度（D）变为-2.77 ± 2.18 D，平均屈光柱误差从-3.14 ± 2.22 变为-2.49 ± 1.71 D（P = 0.089）。平均 max-K 和 mean-K 分别降低了 0.16 ± 2.20 和 0.10 ± 1.69 D。CCT 从 483.87 ± 29.07 μm 增加到 485.95 ± 28.43 μm。顶点前高度从 13.92 ± 8.28 μm 变为 11.45 ± 8.18 μm（P = 0.030），后高度从 29.54 ± 18.39 μm 变为 26.34 ± 19.59 μm。在这 5 年中，mean-K、max-K、UCVA 和散光均未随时间发生变化。CXL 后 1 年，BCVA、MRSE 和 CCT 未发生变化且趋于稳定，而前、后顶点高度则持续下降，直至 CXL 后 5 年。
基于我们的 5 年结果，CXL 治疗进展性圆锥角膜可阻止疾病进展，且不会引起安全性问题，可避免角膜移植。
作者未声明与本文内容相关的经济利益。
