Motion artifact detection in four-dimensional computed tomography images

17th International Conference on the Use of Computers in Radiation Therapy

物理学;计算机科学

Bouilhol, G.^1,2 ; Ayadi, M.^2 ; Pinho, R.^2 ; Rit, S.^1,2 ; Sarrut, D.^1,2

University of Lyon, CREATIS, University Lyon 1, Villeurbanne, France^1

Department of Radiation Oncology, Leon Berard Cancer Center, Lyon, France^2

关键词: Acquisition parameters;    Automatic Detection;    Four-dimensional computed tomography;    Image quality assessment;    Image quality improvements;    Patient breathing;    Radiation therapy treatment planning;    Respiratory phasis;   

Others  :  https://iopscience.iop.org/article/10.1088/1742-6596/489/1/012024/pdf
DOI  :  10.1088/1742-6596/489/1/012024

学科分类：计算机科学（综合）

来源: IOP

【 摘 要 】

Motion artifacts appear in four-dimensional computed tomography (4DCT) images because of suboptimal acquisition parameters or patient breathing irregularities. Frequency of motion artifacts is high and they may introduce errors in radiation therapy treatment planning. Motion artifact detection can be useful for image quality assessment and 4D reconstruction improvement but manual detection in many images is a tedious process. We propose a novel method to evaluate the quality of 4DCT images by automatic detection of motion artifacts. The method was used to evaluate the impact of the optimization of acquisition parameters on image quality at our institute. 4DCT images of 114 lung cancer patients were analyzed. Acquisitions were performed with a rotation period of 0.5 seconds and a pitch of 0.1 (74 patients) or 0.081 (40 patients). A sensitivity of 0.70 and a specificity of 0.97 were observed. End-exhale phases were less prone to motion artifacts. In phases where motion speed is high, the number of detected artifacts was systematically reduced with a pitch of 0.081 instead of 0.1 and the mean reduction was 0.79. The increase of the number of patients with no artifact detected was statistically significant for the 10%, 70% and 80% respiratory phases, indicating a substantial image quality improvement.