gms | German Medical Science

Objective: To define and evaluate various Descemet-graft unfolding techniques in Descemet membrane endothelial keratoplasty (DMEK).

Setting/Venue: Retrospective surgical video analysis at a tertiary referral center.

Method: The surgical videos of 100 consecutive DMEK cases (100 patients) with at least six months of follow up were reviewed by a masked observer. Descemet-graft unfolding methods were categorized into four basic and three auxiliary techniques and their efficacy was evaluated using linear regression analysis. Best corrected visual acuity (BCVA), endothelial cell density and postoperative complications at six months were assessed.

Result: All DMEK surgeries could be completed using four Descemet-graft unfolding techniques: Technique I: standardized ‘no-touch’ graft unfolding using a ‘double-roll’, Technique II: carpet-unrolling while fixating one graft-edge (‘Dirisamer technique’), Technique III: small air-bubble assisted unrolling (‘Dapena maneuver’), and Technique IV: the ‘single sliding cannula maneuver’. Additional maneuvers included: ‘flushing’: turning-over the graft when oriented upside-down; manual graft centration with a cannula; and ‘bubble-bumping’ to unfold peripheral ‘inward folds’. In 73% of surgeries Technique I was used. In 44% a combination of techniques was used, and auxiliary techniques were used in 62%. None of the techniques correlated with the BCVA, endothelial cell density or postoperative complication rate (P>0.1).

Conclusion: DMEK may be further facilitated by using controlled techniques for unfolding the Descemet-graft inside the recipient anterior chamber, either as stand-alone techniques or used in various combinations.