Office-based relaxing incision procedure for correction of astigmatism after deep anterior lamellar keratoplasty

Abstract

Purpose: To report the outcomes of a simple and effective office-based procedure for the correction of astigmatism after deep anterior lamellar keratoplasty (DALK). Methods: This study enrolled 24 consecutive keratoconic eyes that developed an intolerable amount of graft astigmatism after DALK. The location and extension of steep semi-meridians were determined using corneal topography. Office-based relaxing incision procedures were performed at the slit-lamp biomicroscope using a 27-gauge needle. Relaxing incisions were made at the donor-recipient interface on one side of the steepest meridian with an arc length of 45° to 60° and an initial depth of approximately 70–80% of the corneal thickness. Topography was performed after 30–40 minutes and the initial incision was enhanced in depth and length. If an acceptable amount of astigmatism was not achieved, another incision was created at the opposite semi-meridian during the same session. Results: Mean follow-up period was 13.1 ± 7.4 months. Mean preoperative best spectacle corrected visual acuity was 0.26 ± 0.14 logMAR, increasing to 0.22 ± 0.09 logMAR after the procedure (P = 0.20). Mean spherical equivalent refractive error increased from − 4.64 ± 3.06 diopters (D) preoperatively to −6.06 ± 3.15 D postoperatively (P = 0.01). Mean keratometric astigmatism was reduced by 2.95 ± 3.43 D and 5.16 ± 2.97 D measured using subtraction and vector analysis methods, respectively (P < 0.001). Microperforation occurred in one eye, which spontaneously improved with no sequelae. Conclusion: Office-based relaxing incision is a safe and effective procedure for the treatment of corneal graft astigmatism after DALK. This approach effectively decreases the need for the more costly alternative in the operating room.

Keywords

• Astigmatism; Deep Anterior Lamellar Keratoplasty; Office-based Relaxing Incision