Abstract
Purpose:
To evaluate the structural, refractive and visual outcomes of pachymetry assisted lamellar keratoplasty in patients with corneal ectasia.
Methods:
Prospective, non-randomized consecutive case series. Patients with corneal ectasia who underwent unilateral surgery using custom pachymetry assisted lamellar keratoplasty (PALK) were evaluated. Host corneas were treated using transepithelial excimer laser ablation planned to leave 100µm of stromal residual bed. Donor cornea endothelium and Descemet membrane were removed mechanically and then secured to the host cornea with 16 interrupted 10-0 nylon sutures. Eyes were examined preoperatively, day 1, month 1, 3, 6 and 12 postoperatively. Outcome measures were corrected distance visual acuity (CDVA), manifest and keratometric refraction, endothelial rejection episodes, conversion to penetrating keratoplasty (PKP), corneal thickness and endothelial cell density (ECD).
Results:
Five patients with keratoconus grade III and IV (Amsler-Krumeich) and one patient with post-LASIK ectasia were treated with PALK. Average follow up was 3.8 months. The mean postoperative CDVA was LogMAR 0.44 (±0.37)(p=0.02). The mean postoperative manifest spherical equivalent was -3.00±1.01 (p=0.01) and the mean postoperative keratometric reading was 41.51±2.60 (p=0.01). Postoperative central corneal thickness improved to 689.16±29.64 (p<0.001). No endothelial rejection episodes or statistically significant changes in mean ECD were observed. None of the cases had conversion to PKP.
Conclusions:
PALK is an effective, predictable, reproducible and safe technique; dodges the surgeon learning curve and the intraoperative complications that can emerge from other deep anterior lamellar keratoplasty techniques. Further assessment is focused on guaranteeing the long-term safety and stability of the visual outcomes.
Keywords: 479 cornea: clinical science •
741 transplantation •
574 keratoconus