Differences of internal target areas delineated from maximum intensity projection image versus four-dimensional computed tomography image of lung tumor(PDF)
《中国医学物理学杂志》[ISSN:1005-202X/CN:44-1351/R]
- Issue:
- 2018年第2期
- Page:
- 135-140
- Research Field:
- 医学放射物理
- Publishing date:
Info
- Title:
- Differences of internal target areas delineated from maximum intensity projection image versus four-dimensional computed tomography image of lung tumor
- Author(s):
- SONG Mengmeng1; WANG Yunlai2; HUANG Xiang2; JU Zhongjian2; DAI Xiangkun2; WU Qingnan1
- 1. School of Physics and Technology, Wuhan University, Wuhan 430072, China; 2. Department of Radiotherapy, Chinese PLA General Hospital, Beijing 100853, China
- Keywords:
- ; lung tumor; internal target area; four-dimensional computed tomography; maximum intensity projection image; dice coefficient; maximum Hausdorff distance
- PACS:
- R734.2
- DOI:
- DOI:10.3969/j.issn.1005-202X.2018.02.003
- Abstract:
- Objective To evaluate the differences of the volume and shape of lung tumor delineated from maximum intensity projection (MIP) image and four-dimensional computed tomography (4DCT) image of patients with lung tumors located at different positions. Methods Twelve patients with lung tumor were selected, whose tumor located in the central lungs, near the chest wall, close to the thorax, near the blood vessels and heart, and accompanied with lung atelectasis and lymph node metastasis. MIM software was used to process 4DCT images which were acquired by spiral scanning during free breathing for obtaining MIP images and average intensity projection (AIP) images. After being delineated by the same doctor based on the 4DCT images, the gross tumor target areas (GTV0%, GTV10% and GTV90%) were combined as an inner tumor volume (ITV4D). Simultaneously, ITVMIP and GTVAIP were delineated in MIP images and AIP images. The volume and centroid coordinate of ITVMIP and ITV4D were read; the dice coefficient and maximum Hausdorff distance of ITVMIP and ITV4D were also calculated. Results Both the dice coefficient and volume ratio between ITVMIP and ITV4D were beyond 0.9, and the average difference was 0.06 for 7 patients whose tumors were in the central lungs or close to the chest wall; the maximum Hausdorff distance and centroid displacement were 3.20 and 0.65 mm, respectively. The dice coefficient and volume ratio between ITVMIP and ITV4D were 0.85 and 0.80, and the average difference was 0.13 for the other 5 patients whose tumors were close to the blood vessels, heart, liver and accompanied with lymph node metastasis and lung atelectasis; the maximum Hausdorff distance and cnetroid displacement were 9.4 and 3.0 mm, respectively. Conclusion ITV from MIP images and 4DCT images is similar for distinguishable boundary tumors. Significant volumetric differences exist in the target areas delineated from MIP images and 4DCT images when the tumors are adjoined to tissues with similar densities.
Last Update: 2018-01-29