Motion Artifacts in CT Scans: A Study by Computer Simulation and Mechanical Phantom

利用電腦模擬與機械假體於電腦斷層掃瞄影像之移動假影之研究

莊賀喬(Ho-Chiao Chuang) ； 邱君洋(Chun-Yang Chiou) ； 田德之(Der-Chi Tien) ； 吳任弘(Ren-Hong Wu) ； 許仲賢(Chung-Hsien Hsu)

《中國機械工程學刊》 32卷2期 (2011/04) Pp. 147-154

https://doi.org/10.29979/JCSME.201104.0007

摘要

電腦斷層掃描在診斷胸部腫瘤時是一項重要的影像工具，然而在進行電腦斷層掃描時，腫瘤會因呼吸運動產生位置及形狀的變化，導致掃描結果會因呼吸運動產生移動假影的現象。這可能造成腫瘤的大小及形狀會受到誤診，進而影響到治療的效果。本研究即發展一套電腦模型，用於模擬腫瘤在電腦斷層掃瞄時，因呼吸運動而產生的移動假影現象。從研究的結果可證明，在正常呼吸下當調整電腦斷層掃瞄時的切層厚度，即可決定量測目標的運動中心與最大位移量。本研究所發展的電腦模型可應用於臨床放射治療時電腦斷層掃描的成像過程，有助於從電腦斷層掃瞄得到的移動假影影像，確定肺腫瘤的實際位置。

並列摘要

Computed tomography (CT) is one of the most important imaging tools in the diagnosis of thoracic tumors. However, during the scanning process, respiratory motion causes changes in the position and shape of the tumor, creating motion artifacts in the CT scan. This can lead to misdiagnosis of the size and position of the tumor, and can influence the effectiveness of treatment. This study develops a computer model of the movement of the thorax, and simulates the movement of a lung tumor caused by breathing during a CT scan. We show that adjusting the CT slice thickness is sufficient to determine the center of motion and the maximum displacement of a target during normal breathing. This model can be applied to clinical CT imaging processes of radiotherapy, and could assist in determining the position of lung tumors from motion artifacts in CT scans.

並列關鍵字

computed tomography ； computer simulation of images ； motion artifact