MAASTRICHT, Netherlands — In a study performed at the University of Frankfurt, Germany, an age-dependent curve of predicted keratoconus progression was developed to help select patients for corneal cross-linking.
“While methods for diagnosing keratoconus have advanced considerably, there is no single validated method for evaluation of progression,” Mehdi Shajari, MD, said at the European Society of Cataract and Refractive Surgeons winter meeting. “This is a concern because progression is a key factor in deciding whether a patient could benefit from cross-linking.”
The study retrospectively analyzed 352 keratoconus eyes of patients aged 17 years to 57 years. Two Scheimpflug images were taken 1 year apart, and changes in the parameters that are conventionally used to evaluate keratoconus, namely Kmax, pachymetry, D-value, and anterior and posterior radius of curvature (ARC and PRC), were plotted against age.
“We found that most of the variables we are using for detection lack consistency and do not respond to clinical findings. The only reliable parameters appear to be D-value, ARC and PRC,” Shajari said.
Using the median as a cut-off value, a curve of age-dependent predicted progression was designed, and based on it, patients were distributed in three cohorts.
“Our recommendation in Frankfurt is to adjust diagnostics, frequency of visits and treatment decisions to the predicted progression rate of these three cohorts,” Shajari said.
While the risk-benefit ratio is in favor of cross-linking in the first cohort of patients up to 25 years of age with the fastest progression, a more critical evaluation is required in the second group, and cross-linking is not an indication in the third cohort of patients over the age of 35 years. – by Michela Cimberle
Shajari M, et al. Keratoconus progression evaluation. European Society of Cataract and Refractive Surgeons winter meeting; Feb. 10-12, 2017; Maastricht, Netherlands.
Disclosure: Shajari reports no relevant financial disclosures.