One-year Observational Study of an Iris Camera Corneal Opacification Measurement and Pentacam Densitometry in Keratoconus after Corneal Crosslinking

Abstract

\n Purpose: To investigate levels of corneal haze in adult patients with keratoconus treated by corneal crosslinking, using Iris camera and Corneal densitometry imaging. Methods: This was a prospective, observational cross-sectional study on patients attending the Manchester Royal Eye Hospital outpatient department. Iris camera, Pentacam densitometry and visual acuity measurements were collected from patients in two groups. In group A, patients were assessed before and after crosslinking (CXL), whereas in group B, measurements were made for an extended period after their CXL had been performed. Results: Group A consisted of 13 eyes of 13 patients, and group B consisted of 41 eyes of 41 patients. In group A average age was 26.69 (7.19) years. Average time of measurements taken before CXL was 1.85 (0.80) months and after CXL 12.69 (0.63) months. When comparing values before CXL and after, there was a significantly decreased COM score (P=0.001) and Pentacam Corneal densitometry measurement (P=0.003) representing improved corneal clarity. There was a corresponding significant improvement in vision in all eyes in group A after CXL procedure, and 100% of eyes reached a BCVA of ≤20/50 (≤0.4 LogMAR) (P=0.002). In group B, the mean first examination time was post-treatment 3.24 (1.48) months and for the second examination, post-treatment 12.56 (0.81) months. Between these two visits, there was a significant decrease in COM score (P=0.002) and corneal densitometry (P=0.0004) as well as improvement in BCVA (P=0.0002). In this group also, 100% of eyes reached a BCVA of ≤20/50 (≤0.4 LogMAR) by the time of their last follow up. Conclusion: There is a significant improvement in corneal opacification measures using both Iris camera and densitometry when assessing before and after CXL and also sequentially 3 and 12 months after the procedure. The iris camera represents a promising, portable and practical means of assessing and monitoring corneal clarity for this purpose.