Surgically integrated swept source optical coherence tomography (SSOCT) to guide vitreoretinal (VR) surgery

Abstract

 

Purpose

 

To investigate the application and utility of surgically integrated real-time SSOCT to guide VR surgery

 

Methods

 

We developed a microscope-integrated high speed swept-source OCT system capable of live full volumetric imaging at 2-10 volumes/sec with 4D (3-dimensional + time) heads-up display and surgeon control of scanning and display during surgery. In a research lab, we tested all aspects of the system in real-time use during model/porcine eye VR surgical maneuvers including: 1) conventional intraoperative viewing augmented by MIOCT during macular VR maneuvers, 2) same maneuvers with fiberoptic illumination turned off (in the dark) for MIOCT guidance alone; 3) Stereo viewing MIOCT display through both surgical microscope oculars versus with 3D goggles viewing a 3D display screen. In the operating room (OR), under an approved protocol with informed consent, the MIOCT system was utilized in patients as in 1) above.

 

Results

 

In the OR, surgeons: a) viewed macular surgical maneuvers (1C) simultaneous with a high-contrast 4D MIOCT visible directly in the microscope oculars in real-time (1A) while operating, b) pivoted and tilted the 4D MIOCT view in real time via foot control, c) viewed simultaneous B-scans of a selected location within the 3D volume (1B), d) turned OCT images on and off without affecting the surgical view. Surgeons preferred heads up 4D display in the microscope oculars versus cross-sectional B-scans alone. Retinal deformation was visible across the macular area in the 4D view during maneuvers. Changes in specific deep retinal structures such as photoreceptor-retinal pigment epithelium interface were more easily viewed in B-scans, in replay and after further image processing.<br /> In the wetlab, surgeons performed all of the above, and without endoillumination operated with only the 4D MIOCT view. Both within the oculars and on an external screen, 4D heads up display provided information to perform precise macular surgical tasks. Orientation and alignment of the image to the surgeon and surgical instruments were useful for accurate, smooth maneuvers at and across the retinal surface.

 

Conclusions

 

An integrated 4D MIOCT system with surgeon control of scanning and view is a useful adjunct in macular surgery. True OCT-guided VR surgery without need for a conventional microscope view is achievable in the laboratory.  

 

Intraoperative 3D (A) & B-scan (B) MIOCT & membrane peeling (C).