Who is getting clinically significant haze after Corneal Crossolinking for Keratoconus? A Save Sight Keratoconus Registry study

Abstract

Purpose : Following corneal cross-linking (CXL) haze may occur commonly with no long-term impacts on vision. In some patients haze maybe persistent and reduce vision. Further data is needed to understand who is at risk of such ‘clinically significant’ haze. We report the characteristics of patients undergoing CXL for keratoconus in routine clinical practice who developed clinically significant haze.

Methods : The database, the Save Sight Keratoconus Registry, collected data from routine clinical practice in Australia, New Zealand and Europe. Patient demographics, medical history and index visit characteristics, such as visual acuity (VA, in Logarithm of the Minimal Angle of Resolution [logMAR] letters), maximum keratometry [Kmax], pachymetry, as well as treatment parameters (epithelial status, riboflavin type, UV duration), outcomes (VA, Kmax, pachymetry) were recorded in the prospectively designed electronic database along with the occurrence of clinically significant haze.

Results : For the cohort of patients with 12-months follow-up (688 eyes), there were 161 cases of clinically significant haze in 95 eyes. Patients developing haze within 12 months had mean age 22.5 years (SD = 7.0), 26.2% female, baseline vision 63.2 letters (SD = 20.8), Kmax 57.1 dioptres (SD = 6.7), K2 49.8 dioptres (SD = 4.3), and pachymetry 463.1µm (SD = 33.7). Of the eyes that developed haze, 69.5% of eyes underwent short CXL (≤10 minutes) versus 61.9% in eyes that did not develop haze. Univariable analysis suggested patients that developed haze were younger, and had slightly higher Kmax than those that did not develop haze (22.5 vs. 26.8 years, P < 0.001; 57.7D vs. 55.7D, P = 0.045). No other variables were significantly associated with clinically significant haze.

Conclusions : Clinically significant haze was more common in patients who were younger and had steeper keratometry. Post-operative treatment protocols, including the frequency of topical steroid use, may need to be tailored to individual patients such as those at higher risk of clinically significant haze to preserve vision.

This is a 2020 ARVO Annual Meeting abstract.