Abstract
Purpose :
In the current standard corneal collagen crosslinking treatment method, the epithelial debridement can cause severe pain and visual loss during the first few days after treatment. We developed the novel technology of violet light (VL) emitting glass which has the potential to prevent the progression of corneal ectasia without epithelial removal. We also defined the combination of VL irradiation and riboflavin treatment as KeraVio. To evaluate the clinical results of KeraVio in patients with progressive corneal ectasia.
Methods :
Patients with a history of progressive corneal ectasia were recruited in this prospective case series study. Eyes exposed to VL (peak wavelength: 375 nm, irradiance: 310 μW/cm2) emitting glasses for 3 hours daily for 6 months, during which riboflavin solution (flavin adenine dinucleotide 0.05%) was simultaneously repeated 6 times during the VL irradiation under epithelium-on cornea. Corneal topography, uncorrected and corrected distance visual acuity, cylindrical refraction, slit-lamp examination, and measurement of endothelial cell density were evaluated at baseline and at 1, 3, 6 months after KeraVio. We compared the results at 6 months after KeraVio treatment with those from the baseline as well as the trend of changes over the 6-month study period.
Results :
The study enrolled 8 patients. Anterior maximum K (Kmax), posterior average K values, thinnest corneal thickness, as well as visual acuity and cylindrical refraction remained stable over the 6-month follow-up (ANOVA, p≥0.870). No significant decrease in endothelial cell density was observed and corneal and lens transparency remained unchanged. The mean increase in Kmax over the preceding 1 year before baseline and the during 6-month observation period was 2.67 ± 2.23 diopters (D) and 0.31 ± 1.41 D (p=0.031). Similarly, the mean change in corrected distance visual acuity over time was 0.14 ± 0.19 logMAR and -0.06 ± 0.15 logMAR, respectively (p=0.214).
Conclusions :
Based on our 6-month results, daily treatment of progressive corneal ectasia with KeraVio can halt disease progression, without raising any concern for safety. KeraVio may be another minimally invasive treatment option for patients with corneal ectasia. Further studies are needed to confirm these findings and to determine the optimal dosage protocol of VL and riboflavin.
This abstract was presented at the 2019 ARVO Annual Meeting, held in Vancouver, Canada, April 28 - May 2, 2019.