Same-Size Donor Corneas for Myopic Keratoconus

Objective: To determine the efficacy of using same-size donor grafts for keratoconus patients with axial myopia. Methods: A prospective noncomparative interventional case series was performed on 142 eyes of 136 consecutive keratoconus patients. Penetrating keratoplasty (PKP) was performed by 3 skilled surgeons using the same technique with a single running 10-0 nylon suture. Donor button size was determined by a study protocol, where a same-size donor was used for eyes with an axial length (AXL) longer than 24.50 mm, whereas a 0.25-mm-oversized donor was used for eyes shorter than 24.49 mm. Postoperative spherical equivalent (SE) and incidence of postoperative complications were analyzed. Results: Of the 142 consecutive eyes, 123 eyes were operated according to protocol. The average postoperative SE on last visit was -3.94 ± 3.21 D, with an average uncorrected visual acuity of 0.28 (0.90 average corrected). Postoperative SE correlated inversely (r = 0.46) with preoperative axial length (AXL) expressed by the equation: SE = -0.15 (AXL) ² + 6.40 (AXL) - 71.82. Graft rejection was observed in 7 eyes (5.7%), and glaucoma in 2 eyes that required surgery. Conclusions: Using same-size donor grafts in keratoconus patients with a long visual axis is a safe and effective procedure in reducing postoperative myopia.