Factors Predictive of Double Anterior Chamber Formation Following Deep Anterior Lamellar Keratoplasty

Purpose: To identify risk factors predictive of postoperative double anterior chamber formation after deep anterior lamellar keratoplasty (DALK). Design: Retrospective institutional cohort study. Methods: The study group included all consecutive eyes undergoing primary DALK between May 2015 and October 2018 at Villa Igea private hospital (Forli, Italy). The indications for surgery were categorized as (1) keratoconus without scarring; (2) keratoconus with scarring; (3) non-keratoconus without scarring; and (4) non-keratoconus with scarring. Multivariate binary logistic regression analysis was performed, introducing, as independent variables, those that reached a significance level of less than.05 in univariate analysis. The main outcome measure was whether or not postoperative double anterior chamber (AC) occurred. Results: A total of 591 eyes of 591 patients were included. The main indication for DALK was keratoconus (67.2%, n = 397), and pneumatic dissection was achieved in 72.9% (n = 431) of patients. Postoperative double AC was observed in 8.1% (n = 48) of cases. Age, intraoperative central DM perforation, type 2 bubble formation, and presence of scar in keratoconic and nonkeratoconic corneas were all associated with an increased risk of postoperative double AC formation in the univariate analysis. Manual dissection was not associated with double AC formation. The factors that remained significant in multivariate analysis were keratoconus with scarring (odds ratio [OR] = 3.56, P =.02), non-keratoconus with scarring (OR = 5.09, P =.002), intraoperative central perforation (OR = 6.09, P =.03), and type 2 bubble formation (OR = 14.17, P <.001). Conclusions: Scarred corneas of both normal and abnormal shape are independent risk factors for double AC formation following DALK, along with intraoperative perforation and the occurrence of a type 2 bubble.