INTRAOPERATIVE OPTICAL COHERENCE TOMOGRAPHY (OCT) GUIDANCE OF VITREORETINAL SURGERY

Background: Multiple studies have described the utility of intraoperative spectral-domain OCT (SD-OCT) with two dimensional (2D) B-scan imaging in the management of numerous vitreoretinal disorders including macular holes, vitreomacular traction disorders, epiretinal membranes and retinal detachment. Some of these studies also described post-processing of the 2D B-scans to obtain 3D images. With the advancement of intraoperative OCT technology, live volumetric (4D, i.e. 3D over time) visualization of different anterior and posterior segment surgeries has been described in recent studies using intraoperative swept-source microscope-integrated OCT (SS-MIOCT). Our study aims to explore the potential utility of SS-MIOCT during vitrectomy for complications of proliferative diabetic retinopathy. Aim of the work: To evaluate the use of live volumetric (4D) intraoperative swept-source microscope-integrated OCT (SS-MIOCT) in vitrectomy for proliferative diabetic retinopathy (PDR) complications.Patient and Methods: In this prospective study, we analyzed a subgroup of cases with PDR complications that required vitrectomy and that were imaged by the research SS-MIOCT system. In near real time, images were displayed in stereo heads-up display facilitating intraoperative surgeon feedback. Postoperative review included scoring image quality, identifying different diabetic retinopathy (DR)-associated pathologies and reviewing the intraoperatively documented surgeon feedback.Results: Twenty eyes were included. Indications for vitrectomy were tractional retinal detachment (TRD, 16 eyes), combined tractional-rhegmatogenous retinal detachment (2 eyes) and vitreous hemorrhage (2 eyes). Useful, good quality 2D (B-scans) and 4D images were obtained in 16/20 eyes (80%). In these eyes, multiple DR pathologies could be imaged. SS-MIOCT provided surgical guidance, e.g. in identifying dissection planes under fibrovascular membranes, and in determining residual membranes and traction that would benefit from additional peeling. In 4/20 eyes (20%) acceptable images were captured, but they were not useful due to high TRD elevation which was challenging for imaging.Conclusion: SS-MIOCT can provide important guidance during surgery for PDR complications through intraoperative identification of different pathologies and facilitation of intraoperative decision making.