Developing a wireless stereoscopic optical palpation probe towards cost effective intraoperative breast cancer detection

Optical coherence tomography (OCT)-based elastography techniques, such as optical palpation, have shown promise for breast tumor margin assessment. However, the high cost and bulk of OCT systems may limit their clinical feasibility. Here, we present a wireless optical palpation probe utilizing stereoscopic cameras, offering a cost-effective and portable alternative. This stereoscopic optical palpation (SOP) probe measures the deformation of a silicone layer embedded with phosphorescent microparticles. Under UV illumination, these particles emit visible light, allowing the cameras to capture 2D strain images of the layer when compressed against the tissue. These strain images are then converted into stress maps based on the pre-characterized mechanical properties of the silicone layer. The probe is constructed with a 3D-printed case, housing the cameras, a Wi-Fi transceiver, and a rechargeable battery. Real-time video feeds are transmitted to a laptop for stress image processing. We demonstrated the SOP probe on silicone inclusion phantoms, identifying the location of embedded stiff silicone inclusions based on elevated stress measurements caused by increased mechanical contrast. The SOP probe offers a compact, cost-effective solution for real-time breast tumor margin assessment on excised specimens and also holds potential for in vivo detection of residual tumor in the surgical cavity. The low cost, portability, and accessibility of the probe make it suitable for widespread application, including in resource-limited settings. Future work will focus on enhancing measurement accuracy and estimating tissue elasticity to further improve clinical utility.