Comparison between femtosecond laser mushroom configuration and manual trephine straight-edge configuration deep anterior lamellar keratoplasty

Aim: To compare outcomes and complications of femtosecond laser (FSL) mushroom con figuration and manual trephine (MT) straight-edge configuration deep anterior lamellar keratoplasty (DALK). Methods: A cohort of 19 consecutive eyes that underwent FSL DALK was compared with 19 consecutive eyes that underwent MT DALK. Surgery was performed for eyes with keratoconus, corneal ectasia and scarring. Patient demographics, best-corrected visual acuities (BCVAs), refraction and complications were compared. Results: Groups were comparable for age, gender and preoperative BCVA. Rates of intraoperative and postoperative complications were low and comparable between the groups. These included intraoperative Descemet's membrane (DM) perforation which did not require conversion to penetrating keratoplasty; stromal rejection successfully treated with topical steroids; postoperative DM detachment; delayed epithelial healing and increased intraocular pressure which resolved with topical anti-glaucoma drops. At 3 months, the mean BCVA was significantly better in the FSL group compared with the MT group (p=0.00002). At 6 months and 1 year, there was no significant difference between mean BCVA between the two groups. Mean spherical equivalent, cylindrical astigmatism and keratometric cylinder preoperatively and at 3, 6 and 12 months postoperatively were similar between the two groups. Conclusions: FSL or trephine DALK are viable options for keratoconus, ectasia and corneal scars. Earlier visual recovery occurs with FSL mushroom configuration compared with MT straight-edge DALK.