Introduction

The advent of the femtosecond laser in ophthalmology allows precise and customised corneal graft configurations at the graft-host junction. Recent studies have yielded a variety of wound shapes, all of which increase the surface area at the graft-host junction, resulting in better wound approximation, faster healing and earlier suture removal with comparable or reduced astigmatism.1–5 Among them, the mushroom and top hat configurations have been shown to be mechanically more stable than the traditional penetrating keratoplasty (PK) and other wound shapes when sutures were applied.5 This enhanced stability was attributed to the peripheral flange that acts as a valve and prevents wound leakage.

In this study, we developed a novel ‘lock-and-key’ configuration for PK …