The DISCOVER Study 3-Year Results: Feasibility and Usefulness of Microscope-Integrated Intraoperative OCT during Ophthalmic Surgery

Abstract

Purpose: To report the 3-year assessment of feasibility and usefulness of microscope-integrated intraoperative OCT (iOCT) during ophthalmic surgery.

Design: Prospective, consecutive case series.

Participants: Adult participants undergoing incisional ophthalmic surgery with iOCT imaging who consented to be enrolled in the Determination of Feasibility of Intraoperative Spectral-Domain Microscope Combined/Integrated OCT Visualization during En Face Retinal and Ophthalmic Surgery (DISCOVER) study.

Methods: The DISCOVER study is a single-site, multisurgeon, institutional review board-approved investigational device prospective study. Participants included patients undergoing anterior or posterior segment surgery who underwent iOCT imaging with 1 of 3 prototype microscope-integrated iOCT systems (i.e., Zeiss Rescan 700, Leica EnFocus, or Cole Eye iOCT systems). Clinical characteristics were documented, iOCT was directed by the operating surgeon at predetermined surgical time points, and each surgeon completed a questionnaire after surgery to evaluate the usefulness of iOCT during surgery.

Main outcome measures: Feasibility of iOCT based ability to obtain an OCT image during surgery and usefulness of iOCT based on surgeon reporting during surgery.

Results: Eight hundred thirty-seven eyes (244 anterior segment cases and 593 posterior segment cases) were enrolled in the DISCOVER study. Intraoperative OCT demonstrated feasibility with successful image acquisition in 820 eyes (98.0%; 95% confidence interval [CI], 96.8%-98.8%). In 106 anterior segment cases (43.4%; 95% CI, 37.1%-49.9%), the surgeons indicated that the iOCT information impacted their surgical decision making and altered the procedure. In posterior segment procedures, surgeons reported that iOCT enabled altered surgical decision making during the procedure in 173 cases (29.2%; 95% CI, 25.5%-33.0%).

Conclusions: The DISCOVER iOCT study demonstrated both generalized feasibility and usefulness based on the surgeon-reported impact on surgical decision making. This large-scale study confirmed similar findings from other studies on the potential value and impact of iOCT on ophthalmic surgery.

Conflict of interest statement

Conflict of Interest Statement: JPE and SKS have a license agreement with Bioptigen for an external mount system related to intraoperative OCT and a license option agreement with Synergetics related to the development OCT compatible surgical instruments. WJD performs sponsored research with Zeiss related to computational modeling of laser refractive surgery that is unrelated to the current study. None of these relationships are specifically related to the contents of this report. This relationship is not specifically relevant to the findings of the study. No other specific conflicts of interest exist related to this study for any of the other authors.

Copyright © 2018 American Academy of Ophthalmology. Published by Elsevier Inc. All rights reserved.

Figures

Figure 1

Intraoperative Optical Coherence Tomography (iOCT) in Anterior Segment Surgery. (A) iOCT during corneal inlay procedure evaluating channel dissection depth (arrowhead). (B) iOCT following corneal inlay placement (arrow) within the cornea. (C) iOCT during deep anterior lamellar keratoplasty (DALK) following injection of air bubble for big bubble creation. (D) iOCT during DALK following anterior stromal removal revealing minimal stromal bed and Descemet membrane (arrowhead). (E) iOCT during Descemet stripping automated endothelial keratoplasty (DSAEK) following graft placement an dair infusion demonstrating small persistent fluid interface visible on iOCT (arrowhead) but subclinical on microscope view. (F) Intraoperative evaluation of corneal thickness prior to initating the surgical procedure demonstrating severe central corneal thinning on iOCT (arrowhead). (G) iOCT confirmation of intraocular lens placement with visualization of the posterior capsule (arrow). (H) iOCT during Descemet membrane endothelial keratoplasty (DMEK) procedure providing visualization of the graft within the anterior chamber (arrow).

Figure 2

Intraoperative Optical Coherence Tomography (iOCT) with Deep Range Systems and Real-time Feedback. (A) Deep range system provides excellent visualization of the entire anterior chamber from anterior cornea to the anterior surface of the intraocular lens. (B) iOCT during a Descemet membrane endothelial keratoplasty (DMEK) procedure demonstrating excellent visualization of the graft (arrowhead) as well as extensive debris (asterisk) in the anterior chamber. (C–E) iOCT during membrane peeling procedure that demonstrates the pre-peel OCT with epiretinal membrane (arrowhead, C), post-peel with residual membrane (arrow, D) and post-second peel iOCT (E) demonstrating complete membrane removal.

Figure 3

Intraoperative Optical Coherence Tomography (iOCT) in Posterior Segment Surgery. (A) Real-time iOCT during retinal detachment repair visualizing perfluorocarbon liquid placement with progressive displacement of subretinal fluid (arrowhead). Small amounts of residual fluid (asterisk)remain under perfluorocarbon liquid. (B) Following air-fluid exchange, significant reaccumulation of subretinal fluid (asterisk) with associated retinal elevation (arrow) is noted on iOCT that was not clinically apparent, resulting in additional surgical maneuvers to address the subretinal fluid. (C) During macular hole surgery, iOCT is able to identify epiretinal membrane (arrowhead) at hole edge prior to peeling. (D) Following membrane peeling, iOCT confirms complete peel and also demonstrates changes in hole contour and size (arrowhead). (E) After elevating the hyaloid a small subclinical potential full-thickness macular hole was noted on iOCT (arrow). This resulted in additional internal limiting membrane peeling and gas tamponade placement. (F) Real-time iOCT-guided epiretinal membrane removal (arrow).

Figure 4

Intraoperative Optical Coherence Tomography (iOCT) in the Retinal Periphery. (A–B) During scleral depression an area of lattice with mild retinal traction was noted on surgical view. However, iOCT demonstrates what was appeared to be a traction retinal detachment (arrowhead, A), but with additional iOCT inspection a definitive retinal break is noted (arrow, B) which resulted in additional laser photocoagulation and tamponade placement. (C) During vitrectomy for blunt trauma, surgical view demonstrated whitening at the retinal surface that was initially thought to be severe commotion. However, iOCT confirmed that this area of whitening was dehemoglobinized preretinal hemorrhage with underlying shadowing (arrowhead). (D) Intraoperatively, an area of hemorrhage was noted in the inferotemporal quadrant. Initially this was thought to be subretinal based on clinical appearance. iOCT demonstrated that this was actually a small suprachoroidal hemorrhage with expansion of the choroidal space (arrowhead). (E–F) Following air-fluid exchange during retinal detachment repair, a focal fluid pocket (arrowhead) is noted adjacent to the retinal tear (asterisk). iOCT confirms that the pocket is subretinal perfluorocarbon liquid (arrowheads) which was subsequently addressed during the surgery.

Figure 5

Intraoperative Optical Coherence Tomography (iOCT) in Proliferative Diabetic Retinopathy. (A–C) Complex tractional retinal detachment with suspected full-thickness macular hole on iOCT with associated significant vitreomacular traction (A). Real-time iOCT was utilized during membrane removal to visualize dissection plane (B). Following maximal membrane removal, the fovea is inspected and no full-thickness macular hole is visualized (C), which impacted positioning and tamponade choice. (D–E) Extensive tractional detachment with associated thick fibrovascular multi-layer membrane at nerve (D) and throughout the macula (E). iOCT is utilized to differentiate dissection planes where detached retina is adherent to the membrane and areas where the retina is attached and separated from the membranes (E). (F) iOCT is utilized to inspect an area of fibrovascular traction with associated schisis (double arrow) and retinal detachment (asterisk).

Figure 6

Intraoperative Optical Coherence Tomography (iOCT) During Argus Placement. (A) iOCT visualization of Argus array following placement in the eye. Cross-sectional imaging demonstrates significant distance between inner retina and array (arrowhead). Shadowing is noted from the electrodes (asterisk). (B) Second case of iOCT visualization of Argus array following placement. Cross-sectional imaging demonstrates minimal distance between inner retina and array with good apposition to the retinal surface (arrowhead). (C) Immediately prior to tacking, iOCT demonstrates array with tack hole visible (arrowhead). (D) iOCT during tacking process demonstrates shadowing from tack. The compressed integrated springs are visible on OCT during placement (arrowhead).

Figure 7

Integrating Intraoperative Optical Coherence Tomography (iOCT) into a New Surgical Theater. (A) Operating room layout of 3-dimensional 4K monitor for surgical manipulation (B–D) Examples of iOCT overlay on 3-dimensional monitor (arrowhead, B) for simultaneous surgical visualization of OCT datastream and surgical field, including with wide-angle viewing lens (B) and flat high magnificent contact lens (C, D). Excellent visualization of full-thickness macular hole is noted with iOCT (arrow, C) and residual membrane (arrowhead, D).