Large-Diameter Modified Big-Bubble Deep Anterior Lamellar Keratoplasty in Post–Radial Keratotomy Eyes

Abstract

To report the outcomes of our modified large-diameter (9 mm) big-bubble deep anterior lamellar keratoplasty (DALK) technique with improved success rates of pneumatic dissection in post-radial keratotomy (RK) eyes. Ospedali Privati Forlì, "Villa Igea", Forlì, Italy. Retrospective case series. Modified big-bubble DALK was performed in consecutive post-RK eyes. The technique included large diameter (9-mm) diameter deep partial thickness trephination based on the thinnest anterior segment optical coherence tomography pachymetry value at 9 mm; air injection through a cannula advanced 2 mm centripetally from the base of the trephination; limited stromal clearance of the central 6 mm optical zone; suturing of a 9-mm anterior lamellar graft prepared by microkeratome dissection. Success rate of pneumatic dissection, corrected distance visual acuity (CDVA), keratometric astigmatism and complications were recorded. 8 eyes of 7 patients were included. Pneumatic dissection succeeded in 7 cases (87.5%). CDVA significantly improved from 0.94 ± 0.43 to 0.14 ± 0.06 logMAR (P <.001). All eyes reached Snellen CDVA ≥ 20/40, while 3 eyes (37.5%) reached ≥ 20/25. At the last follow-up, 5 eyes (62.5%) had a final keratometric astigmatism ≤4 D, while 2 eyes (25.0%) had ≤ 2 D. Big-bubble DALK can be successfully performed in post-RK eyes with our standardized technique.