Baksoellah Zainab, Lavy Itay, Baydoun Lamis, Hooijmaijers Hilde C M, van Dijk Korine, Melles Gerrit R J
*Netherlands Institute for Innovative Ocular Surgery, Rotterdam, the Netherlands; and †Melles Cornea Clinic Rotterdam, Rotterdam, the Netherlands.
Cornea. 2017 Dec;36(12):1498-1502. doi: 10.1097/ICO.0000000000001345.
To evaluate changes in maximum keratometry (Kmax), corneal higher-order aberrations (HOAs), and densitometry (backscattered light) up to 1 year after UV cross-linking and their possible relation with changes in the visual outcome.
Retrospective cohort study on 18 eyes of 16 patients, who underwent UV cross-linking after the Dresden protocol for progressive keratoconus or ectasia after laser-assisted in situ keratomileusis. Corrected distance visual acuity (CDVA), Scheimpflug-based corneal tomography, mean image brightness (corneal densitometry) from the anterior 120 μm of the midcornea, and posterior 60 μm of the central 6 mm of the cornea, and HOAs were evaluated.
Kmax at 1 month (59.7 ± 6.0D) after UV cross-linking resembled preoperative Kmax (59.3 ± 6.4D, P = 0.368), decreased until 3 months postoperatively (58.3 ± 6.3D, P = 0.002), and stabilized thereafter (P > 0.227). All postoperative corneal densitometry values were higher than preoperative values in all measured depths (P < 0.05). One-month anterior and total corneal HOAs (4.28 ± 1.64 μm and 3.87 ± 1.62 μm, respectively) resembled preoperative values (4.10 ± 1.70 μm and 3.67 ± 1.62 μm, respectively; P > 0.221) and then decreased until 12 months postoperatively (3.86 ± 1.84 μm and 3.40 ± 1.80 μm, respectively; P < 0.005). Thinnest point thickness decreased from before (442 ± 25 μm) to 3 months postoperatively (427 ± 25 μm, P < 0.001), with no difference at 12 months postoperatively compared with preoperative values (437 ± 29 μm, P = 0.149). CDVA and endothelial cell density remained unchanged (P > 0.345 and P > 0.257, respectively). No relations were found between CDVA and the evaluated parameters (P > 0.05).
One year after UV cross-linking, the observation of stable CDVA and thinnest point thickness, together with reduced Kmax suggests no ectasia progression within the study period in these cases. Although HOAs showed a trend toward improvement, corneal densitometry remained elevated.
评估紫外线交联术后长达1年的最大角膜曲率（Kmax）、角膜高阶像差（HOAs）和密度测量（后向散射光）的变化及其与视觉结果变化的可能关系。
对16例患者的18只眼进行回顾性队列研究，这些患者在采用德累斯顿方案进行紫外线交联后，用于治疗进展性圆锥角膜或准分子原位角膜磨镶术后角膜扩张。评估矫正远视力（CDVA）、基于Scheimpflug的角膜断层扫描、角膜中央前120μm和角膜中央6mm后60μm的平均图像亮度（角膜密度测量）以及HOAs。
紫外线交联术后1个月时的Kmax（59.7±6.0D）与术前Kmax（59.3±6.4D，P = 0.368）相似，术后3个月时下降（58.3±6.3D，P = 0.002），此后稳定（P>0.227）。在所有测量深度，所有术后角膜密度测量值均高于术前值（P<0.05）。术后1个月时角膜前表面和全角膜的HOAs（分别为4.28±1.64μm和3.87±1.62μm）与术前值相似（分别为4.10±1.70μm和3.67±1.62μm；P>0.221），然后在术后12个月时下降（分别为3.86±1.84μm和3.40±1.80μm；P<0.005）。最薄点厚度从术前（442±25μm）降至术后3个月（427±25μm，P<0.001），术后12个月与术前值相比无差异（437±29μm，P = 0.149）。CDVA和内皮细胞密度保持不变（分别为P>0.345和P>0.257）。未发现CDVA与评估参数之间存在相关性（P>0.05）。
紫外线交联术后1年，观察到CDVA和最薄点厚度稳定，同时Kmax降低，表明在研究期间这些病例中没有角膜扩张进展。尽管HOAs显示出改善趋势，但角膜密度测量值仍保持升高。
