automated lamellar therapeutic keratoplasty for surgical treatment of keratoconus

purpose: to evaluate the visual and refractive outcomes of automated lamellar therapeutic keratoplasty (altk) in patients with keratoconus. methods: in this prospective noncomparative clinical trial, altk was performed in 14 eyes of 14 patients with moderate to severe keratoconus. all patients were spectacle and contact lens intolerant.  uncorrected visual acuity (ucva), best corrected visual acuity (bcva), spherical equivalent refraction (se), and refractive, keratometirc and topographic astigmatism were evaluated preoperatively and at one, three, and six months postoperatively and also at least 2 months after complete suture removal. minimum duration of follow up was 8 months. results: the study included 9 male and 5 female subjects with mean age of 26.2±5.5 years (18-36 years). mean ucva was 1.2±0.16 logmar (20/300) preoperatively and 0.55±0.2 logmar (20/70) at the last visit. (p<0.001) mean bcva was 0.8±0.2 logmar (20/120) preoperatively and reached 0.34±0.15 logmar (20/40) at the last visit. (p<0.001) mean se was -6.0±2.4 diopter preoperatively and -2.6±2.0 diopter at last visit. (p<0.001) bcva> 20/40 was achieved in 64.3% of the cases and refractive astigmatism was within 4 diopter in 57% of the subjects at last visit. conclusion: although altk can be used for lamellar keratoplasty in patients with keratoconus, high post-op astigmatism is the major drawback.