Initial results of finger imaging using Photoacoustic Computed Tomography

TL;DR

This study demonstrates the capability of photoacoustic computed tomography to visualize detailed blood vessel structures in a human finger, providing a foundation for future disease detection such as rheumatoid arthritis.

Contribution

The paper introduces a specialized imaging system for finger vascularity, achieving detailed visualization of blood vessels and vascular layers in healthy human fingers.

Findings

Rich detail of digital blood vessels with diameters between 100 μm and 1.5 mm

Visualization of vascular layers including the subpapillary plexus

Detection of acoustic reflections from finger bones and skin

Abstract

We present a photoacoustic computed tomography investigation on a healthy human finger, to image blood vessels with a focus on vascularity across the interphalangeal joints. The cross-sectional images were acquired using an imager specifically developed for this purpose. The images show rich detail of the digital blood vessels with diameters between 100 $\mu$m and 1.5 mm in various orientations and at various depths. Different vascular layers in the skin including the subpapillary plexus could also be visualized. Acoustic reflections on the finger bone of photoacoustic signals from skin were visible in sequential slice images along the finger except at the location of the joint gaps. Not unexpectedly, the healthy synovial membrane at the joint gaps was not detected due to its small size and normal vascularization. Future research will concentrate on studying digits afflicted with rheumatoid arthritis to detect the inflamed synovium with its heightened vascularization, whose characteristics are potential markers for disease activity.