Thermoacoustic Tomography of In Vivo Human Finger Joints

Objective: the purpose of this study was to demonstrate the potential of thermoacoustic tomography (TAT) to reveal anatomic structures of in vivo human finger joints. Methods: all the participating volunteers provided written informed consent. Eight healthy middle and index fingers from five volunteers were imaged in vivo by our TAT imaging system. Axial T1-weighted MR imaging (3.0 T) was used to validate the TAT findings. Comparative analyses between TAT and MRI images were performed in two dimension for all the fingers imaged. Three-dimensional (3-D) images and animations were also obtained for some of the fingers thermoacoustically scanned. Results: various intra- and extra-articular tissues were identified in TAT images in high fidelity. These TAT images matched well with the MRI images. Both the 3-D images and animations effectively displayed the extension and transformation of the entire finger along the axis. Conclusion: TAT can noninvasively visualize anatomic structures of the finger joints based on the electrical properties of the joint tissues. The results obtained indicate that TAT may have the potential to contribute to the detection of joint and bone diseases. Significance: this study represents the first for TAT of in vivo human joints and fingers. This study reveals that TAT can effectively recover both soft and hard tissues of the healthy interphalangeal joints, which provides a foundation for its clinical application to detection and diagnosis of joint and bone diseases.