Prognostic Factors For Long-Term Efficacy Of Pulsed-Light Accelerated Corneal Collagen Cross-Linking With Retention Ring-Assisted Continuous Riboflavin Application In Keratoconus
Published 2023 - 41st Congress of the ESCRS
Reference: PP17.03 | Type: Free paper | DOI: 10.82333/t3vr-aq39
Authors: Chung Young Kim 1 , Seonghwan Kim 2 , Won Jong Choi 1 , Chang Ho Yoon* 1 , Mee Kum Kim 1
1Department of Ophthalmology,Seoul National University Hospital,Seoul,Korea, Republic Of, 2Department of Ophthalmology,Seoul Metropolitan Government Seoul National University Boramae Medical Center,Seoul,Korea, Republic Of
Purpose
We assessed the prognostic factors that impact the long-term efficacy of pulsed-light accelerated corneal collagen cross-linking with retention ring-assisted continuous riboflavin application for 10 minutes in eyes with keratoconus.
Setting
We conducted a retrospective review of medical records of 18 eyes of 16 patients with progressive keratoconus who received accelerated CXL and were followed up for over 3 years at Seoul National University Hospital.
Methods
After epithelial removal, riboflavin (0.1%) containing hydroxypropyl methylcellulose (Vibex Rapid, Avedro Inc. USA) was continuously applied for 10 minutes using an 8.0 mm retention ring. Pulsed-ultraviolet light (wavelength; 365 nm) was irradiated for 8 minutes (1 second on/1 second off; 30mW/cm2, cumulative dose of 7.2 J/cm2). Visual acuity, refractive error, topographic indices (maximal/average/astigmatic keratometric values; Kmax/Kavg/Kastig), central and thinnest corneal thickness (CCT/TCT), and endothelial cell density (ECD) were evaluated for 3 years. Regression analyses were conducted to explore prognostic factors that affect flattening of Kmax in successfully treated eyes.
Results
The success rate was 89% over 60 months, with significant improvements in both best-corrected visual acuity (preop logMAR 0.43 to logMAR 0.22), and spherical equivalent (preop -10.83 ± 2.20 to -9.05D ± 2.99). Topographic indices (Kmax and Kavg) showed a significant decrease, while CCT, TCT, and ECD showed no statistical difference before and after the surgery. In 16 patients with successful halting of progression for 3 years, preoperative Kmax, Kavg, and Kastig were associated with greater Kmax flattening in univariate analysis. Furthermore, preoperative Kastig remained significantly associated with Kmax flattening in multiple regression analysis. The higher the preoperative Kastig, the greater the flattening of Kmax over a 3-year period.
Conclusions
Retention ring-assisted continuous application of riboflavin in pulsed-light accelerated CXL is safe and effective for preventing keratoconic progression for up to 3 years. Preoperative Kastig can serve as a prognostic factor for predicting the flattening efficacy of Kmax three years after the procedure.