Deep Anterior Lamellar Keratoplasty: Can All Ruptures Be Fixed?

Purpose: The aim of this study was to report our experience in managing different types of Descemet membrane (DM) ruptures during deep anterior lamellar keratoplasty (DALK). Methods: This study was a retrospective, consecutive, interventional case series of 1573 DALK procedures conducted on 1244 patients, performed between 2002 and 2017. Inclusion criteria consisted of a minimum of 24-month follow-up. DM rupture incidence, location, and surgical approach for repair were recorded. Postoperative measures were investigated only in eyes that experienced DM ruptures and included best spectacle-corrected visual acuity, endothelial cell loss, double anterior chamber, pupillary block, need for rebubbling, graft clarity, and rejection episodes. Results: One thousand four hundred forty-three eyes met the inclusion criteria. DM ruptures occurred in 119 eyes (8.25%). Seventy-eight percent of DM ruptures were microruptures (≤2 mm), and they occurred more frequently during manual DALK cases. Macroruptures were less frequent (22%), and they occurred more frequently during subtotal and total anterior lamellar keratoplasty (STALK-TALK) cases. In general, DM ruptures mainly occurred in the peripheral cornea (95% of cases). One hundred (84%) of the 119 ruptures resolved by the first postoperative day. Nineteen cases (16%) developed double anterior chamber; all resolved by using different strategies. No intraoperative penetrating keratoplasty conversion was recorded. Pupillary block occurred in 7 cases (5.9%), but no Urrets-Zavalia syndrome was observed. The average postoperative endothelial cell loss was 410 ± 39 cells/mm2 (19%) at 1-year follow-up, and there was no significant difference between cases requiring a rebubbling and cases that did not (P = 0.896). All grafts but one were clear at the last follow-up. Graft failure from endothelial decompensation occurred in this lone case (0.8%). Conclusions: It is worth trying to repair all DM ruptures in DALK, and immediate penetrating keratoplasty conversion should be avoided. Understanding the physiomechanical mechanisms in DALK allows to correctly choose a proper rescue strategy to successfully repair DM ruptures.