Physics-Based iOCT Sonification for Real-time Interaction Awareness in Subretinal Injection

2026-05-14

AI Summary

This study addresses the challenge in subretinal injection surgery wherein surgeons struggle to perceive needle tip position and retinal deformation in real time, risking irreversible damage to the non-regenerative retinal pigment epithelium. To mitigate this, the authors propose a physics-based real-time sonification framework that, for the first time, integrates intraoperative optical coherence tomography (iOCT) video streams with a physically inspired acoustic model. By segmenting retinal layers, tracking the needle tip, and detecting injection-induced deformations, the system generates a structured and scalable auditory mapping. Evaluated on 34 participants, the framework achieved an overall event identification accuracy of 83.4%, significantly outperforming the baseline (60.6%, p<0.001), with particularly strong performance in deformation detection. Its clinical utility was further endorsed by four expert ophthalmologists as promising for intraoperative use.

Abstract

Subretinal injection is a delicate vitreoretinal procedure requiring precise needle placement within the subretinal space while avoiding perforation of the retinal pigment epithelium (RPE), a layer directly beneath the target with extremely limited regenerative capacity. To enhance depth perception during cannula advancement, intraoperative optical coherence tomography (iOCT) offers high-resolution cross-sectional visualization of needle-tissue interaction; however, interpreting these images requires sustained visual attention alongside the en face microscope view, thereby increasing cognitive load during critical phases and placing additional demands on the surgeon's proprioceptive control. In this paper, we propose a structured, real-time sonification framework designed for extensible mapping of iOCT-derived anatomical features into perceptual auditory feedback. The method employs a physics-inspired acoustic model driven by segmented retinal layers from a stream of iOCT B-scans, with needle motion and injection-induced retinal layer displacements serving as excitation inputs to the sound model, enabling perception of tool position and retinal deformation. In a controlled user study (n=34), the proposed sonification achieved high retinal layer identification accuracy and robust detection of retinal deformation-related events, significantly outperforming a state-of-the-art baseline in overall event identification (83.4% vs. 60.6%, p < 0.001), with gains driven primarily by enhanced detection of injection-induced retinal deformation. Evaluation by experts (n=4) confirmed the clinical relevance and potential intraoperative applicability of the method. These results establish structured iOCT sonification as a viable complementary modality for real-time surgical guidance in subretinal injection.

Problem

• subretinal injection
• intraoperative optical coherence tomography
• surgical guidance
• retinal deformation
• cognitive load

Innovation

• iOCT sonification
• real-time auditory feedback
• physics-based acoustic model
• subretinal injection
• retinal deformation detection