碩士 / 國立中央大學 / 機械工程研究所 / 100 / Ultrasonic guided biopsy is the most popular approach to diagnose whether tumor is benign or malignant. However, biopsy by free-hand or using probe-attached guidance device cannot avoid needle deflection and misalignment due to external forces. In addition, the biopsy direction must follow and along the plane of ultrasound image which restrict the flexibility to adjust the needle direction to avoid critic tissues. Therefore, it is hard for physicians to do deep and small tumor biopsy clinically.
In this research, an ultrasound-assisted biopsy navigation system has been developed. By using electromagnetic tracking system and ultrasound positioning technology, the positions of ultrasound images, tumors, and biopsy needle are transferred to the same coordinate system. Real-time image display of the relative position of tumor and biopsy needle tip will assist the physician to plan and guide biopsy direction. Moreover, a biopsy assistive device, using a stepping motor to enable the rotation of the needle, is designed to reduce needle deflection due to external forces. To reduce the influence of liver displacement and deformation to biopsy accuracy due to respiration, a Laser Range Finder is applied to measure the ups and downs of the patient’s chest to control the breath status during insertion is identical to that during ultrasound scanning.
In the experiments, pork liver and pork belly are applied as biopsy phantoms. The results of several experiments show that the average and maximum distance errors of using 18 Gauge needle are 3.17mm and 4.38mm respectively, while the average and maximum distance errors of using 21 Gauge needle are 3.36mm and 4.62mm respectively. It indicates that the developed system should be able to `assist physicians to biopsy deep tumor with a diameter greater than 1cm.
| Identifer | oai:union.ndltd.org:TW/100NCU05489021 |
| Date | January 2012 |
| Creators | Wen-chun Tu, 杜文鈞 |
| Contributors | Ching-shiow Tseng, 曾清秀 |
| Source Sets | National Digital Library of Theses and Dissertations in Taiwan |
| Language | zh-TW |
| Detected Language | English |
| Type | 學位論文 ; thesis |
| Format | 81 |
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