[Functional results of contact lens correction and penetrating keratoplasty in keratoconus. Report 1. Analysis of resolution ability of the eye].

Comparative analysis of functional results of contact lens correction and penetrating keratoplasty (PKP) in keratoconus are presented. To assess resolution ability we considered visual acuity and contrast sensitivity. 117 patients (219 eyes) with stage I-IV keratoconus, wearing rigid gas-permeable contact lenses (RPCL), and 60 patients (64 eyes) after PKP were examined. In 69% patients after PKP non-corrected visual acuity (NCVA) was 0.1 or more and mean best corrected visual acuity (BCVA) was 0.63, that is similar to efficacy of contact lens correction in stage III-IV keratoconus. In 31% patients NCVA after PKP was less than 0.1 due to significant refractive arrow, visual rehabilitation of these patients required use of RPCL or refractive surgery. Contrast sensitivity in medium frequencies after PKP was almost similar to that of contact lens correction in stage III keratoconus, and in high frequencies it was close to that of stage IV.