Assessment of Microarchitectural Changes During Vitrectomy Surgery for Vitreomacular Traction Syndrome Utilizing Intraoperative Optical Coherence Tomography

Abstract

 

Purpose

 

To assess the microarchitectural changes that occur during surgery for vitreomacular traction (VMT) utilizing intraoperative optical coherence tomography (iOCT).

 

Methods

 

Retrospective case series of eyes undergoing pars plana vitrectomy (PPV) for VMT with concurrent iOCT was collected. A microscope-mounted portable spectral domain OCT system (Bioptigen) was used for intraoperative imaging with a standard acquisition protocol (e.g., preincision, following hyaloid elevation). IRB approval was obtained. Qualitative and quantitative assessment of the retinal microarchitectural features was performed.

 

Results

 

Eleven eyes of 11 patients were included with a mean preoperative visual acuity (VA) of 20/72 and improving to 20/46 postoperatively (p = 0.04). No surgical complications were noted. For 2/11 eyes, the preincision iOCT scans showed interval development of subclinical full-thickness macular holes (FTMH). Following hyaloid elevation, one eye showed definitive FTMH formation and an additional eye showed possible FTMH. In all four of these eyes (4/11, 36%), iOCT impacted the surgical procedure to address the subclinical findings (e.g., internal limiting membrane peeling, gas tamponade). Other microarchitectural changes noted with iOCT following hyaloid elevation included increased inner segment-outer segment (IS-OS) disruption and increased subretinal hyporeflectivity with expansion of the distance between the RPE and outer retina (e.g., IS-OS, cone outer segment tips).

 

Conclusions

 

Intrasurgical imaging utilizing iOCT during VMT can impact surgical planning through the detection of subclinical changes (e.g., small FTMH formation). Architectural changes occur following surgical maneuvers that are particularly noted in the outer retina. The functional significance of these changes is currently unknown.

 

 

Figure 1. Intraoperative ophthalmic coherence tomography (iOCT) scans showing (A) vitreomacular traction (arrowheads) with large foveal cyst prior to incision and (B) elevation of IS-OS and COST line following hyaloid removal (box) with reduction in foveal height.

 

 

Figure 2. (A) OCT scan in clinic showing VMT (arrowheads) with outer retinal elevation and (B) intraoperative OCT scan showing interval development of full-thickness macular hole (*) prior to surgical intervention.

 

Keywords: 762 vitreoretinal surgery • 550 imaging/image analysis: clinical • 552 imaging methods (CT, FA, ICG, MRI, OCT, RTA, SLO, ultrasound)