Abstract
Purpose :
To describe the use of intraoperative anterior segment optical coherence tomography (iAS-OCT) as a useful tool to help surgeons better visualize midstromal dissection for Bowman layer (BL) transplantation, and ultimately alter surgical decision making for patients with Keratoconus.
Methods :
21 consecutive eyes of 20 patients with Keratoconus underwent Bowman layer transplantation. Midstromal dissection was facilitated using an operating microscope (Lumera 700; Carl Zeiss Meditec, Inc) fitted with iAS-OCT (Callisto; Carl Zeiss Meditec, Inc). Intra- and postoperative complications (up to 6 months follow-up) were recorded.
Results :
In 19 eyes, BL transplantation aided with iAS-OCT enabled visualization of the dissection plane even in cases for which blood, edema, or scarring otherwise would have obscured the surgeon’s view of the air-endothelial reflex. This allowed dissections proceeding too anteriorly or posteriorly to be course-corrected before inadvertent perforation occurred and proper placement and total unfolding of the donor graft could be confirmed. In 2 eyes, intraoperative perforation during stromal dissection resulted in the operation being aborted. 89% of patients (16/18) demonstrated a reduction in Kmax 1 day postoperatively, which was maintained in 86% of patients (12/14) at 6 months postoperatively. No immediate postoperative complications occurred.
Conclusions :
Particularly during the surgical learning curve, or for surgeons not experienced with manual dissection deep anterior lamellar keratoplasty (DALK), iAS-OCT may enable corneal surgeons to be more confident and comfortable with their stromal dissections and to achieve better results with BL transplantation.
This abstract was presented at the 2019 ARVO Annual Meeting, held in Vancouver, Canada, April 28 - May 2, 2019.