A New Ultrasound Elastography Displacement Estimation Method for Mobile Telemedicine

Traditional medicine requires doctors and patients to engage in face-to-face palpation, which is a great challenge in underdeveloped areas, especially in rural areas. Telemedicine provides an opportunity for patients to connect with doctors who may be thousands of miles away via mobile devices or the Internet. When using this method, elastography is a crucial medical imaging modality that maps the elastic properties of soft tissue, which can then be sent to doctors remotely. Ultrasound elastography has become a research focus because it can accurately measure soft tissue lesions. Displacement estimation is a key step in ultrasound elastography. The phase-zero search method is a popular displacement estimation method that is accurate and rapid. However, the method is ineffective when the displacement is more than a 1/4 wavelength. The block-matching method can address this shortcoming because it is suitable for large displacements, although it is not accurate. Notably, the quality-guided block matching method has exhibited good robustness under complex mutational conditions. In this paper, we propose a novel displacement estimation method that combines the block-matching method and the phase-zero search method. The block-matching method provides prior knowledge to increase the robustness of the phase-zero search under large displacement conditions. The experimental results show that our method exhibits stronger robustness, more accurate results, and faster calculation speed.