FEASIBILITY OF FITTING CONTACT-LENSES WITH APICAL CLEARANCE IN KERATOCONUS

Despite the wide variety of rigid contact lens fitting philosophies fo r the visual correction of keratoconus, questions remain, including wh ich approach-flat, divided support, or steep-contributes the most towa rd the preservation of a clear cornea, One goal of the Collaborative L ongitudinal Evaluation of Keratoconus (CLEK) Pilot Study was to determ ine the feasibility of managing early keratoconus patients with apical clearance rigid contact lenses, Of 30 keratoconus patients identified with at least 1 nonscarred cornea, 17 patients (30 eyes) were randoml y assigned to a steep lens fitting protocol, After trial fitting with a standardized lens design demonstrating minimum apical clearance, len ses were dispensed whose base curve was 0.2 mm steeper than the minimu m apical clearance lens, Patients were re-evaluated on a quarterly sch edule concluding at 12 months, Changes in keratometry between baseline and 12 months identified unequal steepening of the flat and steep cor neal curvatures, suggestive of corneal molding, Best corrected rigid l ens visual acuity measures illustrated no significant changes over the course of the study. Clinically significant corneal compromise was tr ansiently observed in some patients, Only 1 of 22 eyes completing the pilot study and fitted with apical clearance developed mild corneal sc arring.