Validation of a new 3D-US imaging robotic system to detect and quantify lower limb arterial stenoses

Stenosis degree is the most common criterion used to assess the severity of atherosclerosis. This form of peripheral arterial disease (PAD) is often present in lower limb arteries. However, to detect and quantify distributed arterial stenoses in lower limbs, a high precision is required over a long segment. Moreover, to plan the appropriate therapy, a 3D representation of the vessel is desirable. Most 3D-ultrasound (US) developments are not optimally adapted for this application. A new 3D-US imaging robotic system that can control and standardize the 3D-US acquisition process for any scanning distance is presented. A calibration study is performed to determine the spatial transform to relate the US probe image plane attached to the robotic system, to the robot coordinates. Additionally, 3D-US reconstructions of in-vitro stenoses were obtained with the robotic scanner and the spatial calibration transform computed. Thereafter, stenoses were detected and quantified from the 3D reconstructed model. Altogether, these results demonstrate the potential of the robot for the clinical evaluation of lower limb vessels over long and tortuous segments starting from the iliac artery down to the popliteal artery below the knee.