visual function after deep anterior lamellar keratoplasty: descemitic versus pre-descemetic dissection

purpose: to evaluate the effect of posterior residual stroma on visual function after unsuccessful anwar's deep anterior lamellar keratoplasty (dalk). methoods: in this parallel historical cohort, visual acuity and refractive status were evaluated after descemetic dalk (group 1) and compared with those of pre-descemetic dalk (group 2). results: one hundred and ten keratoconic eyes were enrolled. a bare descemet’s membrane (dm) was successfully achieved in 93 (84.5%) eyes in group (1) and 17 (15.4%) eyes in group (2). mean follow-up period was 20±8 and 20±7 months in groups (1) and (2), respectively (p= 0.08). postoperative best spectacle-corrected visual acuity (bscva) was significantly better in group (1) than in group (2) at 1, 3, 6 and 12 months. however, there was no significant difference between study groups at final examination. the two groups were comparable in terms of keratometric astigmatism and spherical equivalent refractive error throughout the follow-up period. conclusion: retention of posterior corneal stroma delays visual recovery after dalk using anwar's technique; however, both descemetic and pre-descemetic methods have acceptable and comparable visual acuity levels at final follow-up.