Feasibility of a markerless tracking system based on optical coherence tomography

TL;DR

This paper explores a novel markerless tracking system using high-speed optical coherence tomography (OCT) to track moving objects in medical applications, offering high resolution and the ability to identify natural landmarks.

Contribution

It introduces a new OCT-based markerless tracking approach capable of high-speed, high-resolution tracking of subsurface structures in moving biological tissues.

Findings

Tracked motion up to 20 mm/s with 0.2 mm error

Effective on structured and homogeneous phantoms

Promising for fast, precise medical tracking

Abstract

Clinical tracking systems are popular but typically require specific tracking markers. During the last years, scanning speed of optical coherence tomography (OCT) has increased to A-scan rates above 1 MHz allowing to acquire volume scans of moving objects. Thorefore, we propose a markerless tracking system based on OCT to obtain small volumetric images including information of sub-surface structures at high spatio-temporal resolution. In contrast to conventional vision based approaches, this allows identifying natural landmarks even for smooth and homogeneous surfaces. We describe the optomechanical setup and process flow to evaluate OCT volumes for translations and accordingly adjust the position of the field-of-view to follow moving samples. While our current setup is still preliminary, we demonstrate tracking of motion transversal to the OCT beam of up to 20 mm/s with errors around 0.2 mm and even better for some scenarios. Tracking is evaluated on a clearly structured and on a homogeneous phantom as well as on actual tissue samples. The results show that OCT is promising for fast and precise tracking of smooth, monochromatic objects in medical scenarios.