Intelligent Virtual B-Scan Mirror (IVBM)

Swept-Source Optical Coherence Tomography (SS-OCT) allows surgeons to perform certain ophthalmic procedures under the exclusive guidance of real-time volumetric optical coherence tomography (4D OCT). In such scenarios, surgeons are no longer limited to rigid views through an operating microscope. Instead, direct volume rendering (DVR) of 4D OCT enables surgical maneuvers to be performed from arbitrary viewpoints. While 4D OCT maximizes the use of the depth-resolved OCT data by displaying it from an oblique perspective, performing complex instrument maneuvers from such views places a higher mental demand on the surgeon. In this work, we propose an Intelligent Virtual B-scan Mirror (IVBM), a novel concept for surgical 4D OCT visualization to provide additional guidance for targeted instrument interactions. The IVBM integrates a virtual mirror into a selected cross-section of the OCT volume. This mirror acts intelligently by only being sensitive to voxels associated with surgical instruments. Furthermore, volume structures aligned with the IVBM are highlighted, while structures behind the IVBM are preserved through an adaptive opacity transfer function. Unlike previous perceptual OCT visualization concepts, which primarily address depth perception in axial OCT direction, this novel approach aids surgical interactions from arbitrary views. This paper presents the definition and implementation of an IVBM in a 4D OCT integrated microscope. Our user study in a virtual simulation environment confirms the benefits and provides insights into the interaction with the concept.