POSTERIOR KERATOCONUS - AN EXPANDED CLASSIFICATION SCHEME BASED ON CORNEAL TOPOGRAPHY

Objective: The purpose of the study was to evaluate corneal changes in posterior keratoconus. Design: A retrospective review. Results: Disti nct topographic patterns were identified. Generalized posterior kerato conus showed uniform corneal steepening. Localized central and paracen tral posterior keratoconus showed corneal steepening, and localized pe ripheral posterior keratoconus showed corneal flattening overlying the area of corneal change. The changes in central and paracentral poster ior keratoconus appear to progress with an increase in patient age. Un ilateral disease may have more amblyogenic potential. Conclusions: Pos terior keratoconus manifests significant corneal surface alterations. The distinct topographic patterns seen probably warrant a further clas sification of localized posterior keratoconus into central-paracentral and peripheral varieties.