Accelerated corneal collagen cross-linking in eyes with incurable bullous keratopathy

Objective To evaluate the efficacy of accelerated corneal collagen cross-linking (a-CXL) in patients with incurable bullous keratopathy. Methods This was a retrospective, nonrandomized study. Patients with incurable bullous keratopathy who were consecutively diagnosed at the hospital of the Affiliated Xiamen Eye Center of Xiamen University from March 2011 to March 2013 were included in the study. Patients received accelerated CXL surgery. The following parameters were accessed preoperatively and 1 week, 1 month and 3 months postoperatively: ocular pain index using the Numeric Rating Scale (NRS), visual acuity, noncontact tonometer measurement, slit-lamp examination for corneal epithelium defects and corneal opacity, and anterior-segment OCT for corneal thickness. Differences between groups were analyzed using one-way ANOVA. Results Thirteen eyes were chosen and underwent a-CXL. The ocular pain index was 7.6±1.2 on average preoperatively and significantly decreased to 5.3±1.6 at 1 month and to 5.5±1.7 at 3 months postoperatively (F=8.593,P<0.01). The corneal epithelial staining score was 4.5±0.5 preoperatively and was significantly reduced to 3.4±0.6 at 1 week and to 2.8±0.9 at 1 month (F=12.580,P<0.01) postoperatively. The corneal transparency score was 2.7±0.5 preoperatively and improved significantly to 1.9±0.5 at 1 week and 2.2±0.6 at 1 month (F=6.122,P<0.01) postoperatively. Preoperative corneal thickness was 862.2±146.4 μm and decreased significantly to 707.5±92.7 μm at 1 week and 718.8±47.2 μm at 1 month (F=5.859 ,P<0.01) postoperatively. At 3 months postoperatively , the corneal epithelial staining score, corneal transparency score and corneal thickness were not significantly different from preoperative conditions. Conclusion Accelerated CXL significantly reduces ocular pain, improves corneal epithelium defects, corneal transparency and corneal thickness within a short period postoperatively. However, a-CXL do not seem to have long-lasting effects in patients with bullous keratopathy. Key words: Corneal collagen cross-linking; Bullous keratopathy; Corneal endothelium; Therapy outcome