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个体化塑形的鼻咽癌多感兴趣区图像配准摆位误差 被引量:1
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作者 曹潘潘 王维青 +5 位作者 成宇 雷金艳 李师 施小龙 彭海燕 靳富 《中国医学物理学杂志》 CSCD 2024年第2期151-157,共7页
目的:探究鼻咽癌个体化塑形多感兴趣区图像配准对摆位误差的影响。方法:随机选取43例鼻咽癌放疗的患者,采用发泡胶个体化塑形联合头颈肩热塑膜对其进行体位固定,每周一次CBCT摆位校准。在CBCT图像上,将感兴趣区(ROI)划分为临床使用的全R... 目的:探究鼻咽癌个体化塑形多感兴趣区图像配准对摆位误差的影响。方法:随机选取43例鼻咽癌放疗的患者,采用发泡胶个体化塑形联合头颈肩热塑膜对其进行体位固定,每周一次CBCT摆位校准。在CBCT图像上,将感兴趣区(ROI)划分为临床使用的全ROI(ROI_(PTV))和7个包含不同颈段结构的局部ROI(ROI_(蝶窦)、ROI_(寰枢椎)、ROI_(颈3)、ROI_(颈4)、ROI_(颈5)、ROI_(颈6)、ROI_(颈7)),分别与定位CT图像配准,记8个ROI在头脚(SI)、左右(LR)、腹背(AP)、Pitch、Roll、Yaw方向的配准误差。结果:SI方向ROI_(颈7)的摆位误差在0.3 cm以内的占89.74%,其余ROI在0.3 cm以内均占90%以上。LR方向随着颈段往上,摆位误差在0.3 cm以内的占比逐渐增加,ROI_(颈7)、ROI_(颈6)、ROI_(颈5)摆位误差在0.3 cm以内的占比分别为76.78%、81.70%和85.26%,其余ROI占比均在90%以上;AP方向除ROI_(寰枢椎)和ROI_(颈3)外,其余ROI摆位误差在0.3 cm以内的占比均低于90%。ROI_(蝶窦)、ROI_(寰枢椎)、ROI_(颈3)、ROI_(颈4)与ROI_(PTV)在SI方向的摆位误差均呈显著正相关(R=0.94、0.95、0.90、0.83);ROI_(蝶窦)与ROI_(寰枢椎)、ROI_(颈3),ROI_(PTV)与ROI_(颈3)在LR方向的摆位误差均呈显著正相关(R=0.95、0.91、0.91);AP方向ROI_(PTV)与ROI_(寰枢椎)、ROI_(颈3)的摆位误差均呈显著正相关(R=0.88、0.90)。8个ROI的外扩为0.38~1.01 cm,其中ROI_(颈6)与ROI_(颈7)在AP方向的外扩均超过0.90 cm,ROI_(颈7)在SI方向的外扩达到0.95 cm。结论:ROI_(PTV)与ROI_(蝶窦)、ROI_(寰枢椎)、ROI_(颈3)在SI、LR和AP方向均存在显著相关性;随着颈段从第三颈椎往下,鼻咽癌患者分段摆位误差逐渐增大;头颈部鼻咽癌患者用发泡胶进行个体化塑形时,鼻咽部和颈椎区域需分段进行外扩。 展开更多
关键词 鼻咽癌 个体化塑形 多感兴趣区 摆位误差
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The Study of Image Segmentation Based on the Combination of the Wavelet Multi-scale Edge Detection and the Entropy Iterative Threshold Selection 被引量:3
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作者 ZHANG Qian HE Jian-feng +3 位作者 MA Lei PAN Li-peng LIU Jun-qing CHEN Hong-lei 《Chinese Journal of Biomedical Engineering(English Edition)》 2013年第4期154-160,共7页
This paper proposes an image segmentation method based on the combination of the wavelet multi-scale edge detection and the entropy iterative threshold selection.Image for segmentation is divided into two parts by hig... This paper proposes an image segmentation method based on the combination of the wavelet multi-scale edge detection and the entropy iterative threshold selection.Image for segmentation is divided into two parts by high- and low-frequency.In the high-frequency part the wavelet multiscale was used for the edge detection,and the low-frequency part conducted on segmentation using the entropy iterative threshold selection method.Through the consideration of the image edge and region,a CT image of the thorax was chosen to test the proposed method for the segmentation of the lungs.Experimental results show that the method is efficient to segment the interesting region of an image compared with conventional methods. 展开更多
关键词 wavelet multi-scale ENTROPY iterative threshold lung images
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