Ultrasonic Renal-Stone Tracking with Mesh Regularization

• Main Authors: Jia-Hong He, 何嘉浤
• Other Authors: Jen-Ho Tsao
• Format: Others
• Language: zh-TW
• Published: 2007
• Online Access: http://ndltd.ncl.edu.tw/handle/12954007746159106870

碩士 === 臺灣大學 === 電機工程學研究所 === 95 === The efficacy of Extracorporeal Shock Wave Lithotripsy (ESWL) depends greatly on the capability to focus shock waves on renal stone. To achieve automatic focusing on moving target, the target must be under tracking. A mesh-based block matching algorithm is proposed for renal stone tracking using ultrasound image sequence. Since multiple targets are tracked together, the mesh-based tracking algorithm can provide a function of contextual regularization for solving the target missing and image degradation problems in renal stone tracking. Recorded ultrasound images of kidney during ESWL treatment are modified for demonstrating the capability of this algorithm. We regard the soft tissue of the body as elastic in order to analyze the relationship of stress, strain, deformable energy and displacement. On the basis of the optimal design, we also define the initial displacement of block-matching to minimum the function of matching error energy and the deformable energy by displacement vector to solve the optimal value of displacement of mesh grid nodes. Therein, we figure out the stiffness matrix of deformable energy by finite element method. In order to simplify the calculation, we choose a regular quadrilateral element as the mesh model to achieve the tracking of real time. According to the optimal design, we amend the performance of block-matching to avoid the damage of renal caused by stone breakers.