A Pilot Study on Feasibility and Effectiveness of Intraoperative Spectral-Domain Optical Coherence Tomography in Glaucoma Procedures.

Abstract

To demonstrate the use of a spectral-domain optical coherence tomography (SDOCT) integrated surgical microscope in glaucoma surgery. An SDOCT system was used to interface directly with an ophthalmic surgical microscope, to allow real-time intraoperative SDOCT (iOCT) imaging during glaucoma procedures like phaco-trabeculectomy, Ahmed glaucoma valve (AGV) implantation, gonio-synechiolysis, and bleb needling. The various surgical steps during glaucoma surgeries where iOCT can be of potential help in guiding the surgeon were recorded. High-resolution, cross-sectional images of the relevant structures were achieved with the iOCT system in all procedures. The surgeon could determine the depth of the scleral dissection, the intrastomal bed, the path of the AGV tube in the eye, the release of peripheral anterior synechiae and the efficacy of needling with respect to breakage of loculations; most of these are technically 'blind' procedures, where the outcomes are determined postoperatively. Metallic instruments cast a shadow on tissues below, thereby restricting the use of the device in its current state. The iOCT system provided high quality, intraoperative, real-time imaging, which could possibly improve the safety and efficacy of the surgical procedures in glaucoma. Further studies and modifications to the iOCT are required to better understand and increase the uptake of this technology in daily practice. The iOCT, with further advancements in its technology, could potentially provide the surgeon both quantitative and qualitative, real-time depth and tissue proximity details, thus improving the safety and accuracy of glaucoma surgery.