Keratoconus: classification scheme based on videokeratography and clinical signs.

Area of Science:

• Ophthalmology
• Corneal Imaging
• Keratoconus Research

Background:

• Keratoconus is a progressive corneal thinning disorder.
• Early detection of keratoconus is crucial for timely intervention.
• Videokeratography offers quantitative measures of corneal topography.

Purpose of the Study:

• To assess the correlation between videokeratography indices and clinical keratoconus signs.
• To evaluate the utility of these correlations for practicing clinicians.
• To determine if quantitative videokeratography can aid in detecting subclinical keratoconus.

Main Methods:

• A longitudinal study followed eyes classified as normal, keratoconus suspect, early keratoconus, or keratoconus.
• Quantitative videokeratography indices including central keratometry (K), inferior-superior (I-S) value, and keratoconus percentage index (KISA) were measured.
• Discriminant analysis was used to evaluate classification rates based on these indices and age over 1-8 years of follow-up.

Main Results:

• Significant baseline differences were observed in K, I-S, and log(KISA) across all groups (P<.001).
• Over a median of 4.1 years, 28% of keratoconus suspects and 75% of early keratoconus cases progressed.
• A classification model using the three indices and age achieved a 68.9% overall accuracy.

Conclusions:

• Longitudinal and cross-sectional data confirm significant differences in videokeratography indices between keratoconus groups.
• The findings suggest that videokeratography-based classification schemes can aid in identifying subclinical keratoconus.
• These quantitative measures may prove valuable for clinicians in diagnosing and monitoring keratoconus.