The use of the same size host and donor trephine in penetrating keratoplasty for keratoconus.

The results of a retrospective analysis of 49 eyes (40 patients) that underwent penetrating keratoplasty for keratoconus are presented. All grafts had the same size trephine for both host and donor corneas. Ninety-eight per cent of eyes achieved a post-operative visual acuity of 6/12 or better; 43% of eyes attained this level of acuity unaided, although more than half of these required spectacles or contact lenses to reach their best corrected acuity. The average post-operative spherical ametropia was -0.5 dioptre (SD 2.97 dioptres) and the average post-operative cylinder was -3.8 dioptres (SD 2.63 dioptres). Three eyes (6%) required keratorefractive surgery to reduce astigmatism. Wound integrity was satisfactory using the same (size) trephine for both host and donor, with no patient suffering a post-operative wound leak or iris prolapse. The reduction of post-operative myopia and astigmatism is discussed.