Visualization of cataract workflow utilizing four-dimensional microscope-integrated optical coherence tomography in an ex vivo porcine eye model

Abstract

Purpose : Optical Coherence Tomography (OCT) is not regularly used in clinical practice in cataract surgeries, due to high costs and lack of demonstrated purposes compared to white light microscopes. It is mostly employed as a pre-and postoperative tool for checkup. We present various forms of visualizations of our microscope-integrated four-dimensional OCT (mi4D-OCT) engine during mock cataract surgery in ex vivo porcine eyes. We provide 4D videos, as well as volume captures and B-scans.

Methods : We performed several mock cataract surgeries in wet labs with ex vivo porcine eyes. Each phase of the surgery was visualized with a novel surgical microscope-integrated MHz SS-OCT engine. The entire cataract procedure was captured, utilizing live 4D-OCT video recordings, live B-scan displays, offline reconstructed B-scan series, and volume capture scans.

Results : We were able to record corneal incision, ophthalmic viscosurgical device injection, and capsulorhexis with the live 4D-OCT rendering display (10 vols/s) at an effective A-scan rate of 1.2 MHz and an imaging depth of 6 mm (see Figure 1). Utilizing the larger imaging depth, we recorded the phacoemulsification (phaco), intraocular lens injection, and the closing of the incision with a live B-scan mode at an A-scan rate of 100 kHz with an imaging depth of 29 mm (see Figure 2 (i) & (ii)). The postoperative position of the IOL in the capsular bag is clearly identifiable (Figure 2 (iii)).

Conclusions : We have demonstrated novel anterior segment visualization capabilities of a fast mi4D-OCT engine during entire mock cataract surgeries. Although no clear verdict exists as to how and at what stage of cataract procedures 4D-OCT visualization is beneficial, we believe that early adaptation will include 4D-OCT derived assistance functions and various forms of live visualization will follow from then on.

This abstract was presented at the 2023 ARVO Imaging in the Eye Conference, held in New Orleans, LA, April 21-22, 2023.

 

Figure 1: 4D-renderings of the piercing for an initial opening for capsulorhexis (i), pulling point at the anterior capsular bag (ii), insertion of tweezers into the anterior chamber (iii), and the start of rhexis (iv). Volumes are displayed in false colors.

 

Figure 2: Visualizations of various late steps during cataract surgery. Capture of live B-scan display including phaco tip (i), a full depth image of postoperative anterior segment including IOL's final position (ii). Rendering of entire segment after surgery (iii).