BACKGROUND: Three case reports of successful rigid gas permeable fittings for patients suffering from delayed onset keratectasia following LASIK will be discussed. LASIK is currently the most common refractive surgical procedure. Despite a high success rate, reports of iatrogenic or delayed onset keratectsia have recently increased. It appears that keratectasia may be a possible late complication of LASIK
CASE REPORT(S). Three patients that had undergone LASIK for high myopia presented with similar complications of keratectesia many years postoperatively to LASIK. All three patients reported rapid decrease in visual acuity and subsequent development of ghost images. Topographies revealed irregular corneas with marked steepening in the inferior portion of the corneas with variable degrees of encroachment of the central visual axis. All three patients were fit with rigid lenses of different designs which included conventional spherical, keratoconic and reverse geometry lenses. Each patient showed adequate fits and achieved improved visual acuities with reduced symptoms of monocular diplopia. In all cases, large diameter lenses were utilized to overcome peripheral corneal irregularities and improve centration. In addition, we noted that particular areas of corneal steepening demonstrated more success with specific lens designs. Corneas with steep zones within 5 mm of the visual axis were most successful with keratoconic design lenses. In some cases, corneas demonstrating peripheral steepening required reverse geometry designs to establish lens fits.
CONCLUSIONS. Rigid gas permeables proved to be an excellent alternative to restore visual acuity and minimize monocular diplopic symptoms for patients with late onset keratectasia following LASIK. Success was found utilizing large diameter spherical, keratoconic and reverse geometry lenses. This poster will present topographical maps for each patient, details of the contact lens parameters chosen for each fit and explain why specific lens designs were selected for each case. Keratoconic lenses were successful for corneas with steepening within 5 mm of the visual axis and reverse geometry lenses achieved good fits with peripheral corneal steepening.