Original article: Esophageal motion during radiotherapy: quantification and margin implications

摘要: The purpose was to evaluate interfraction and intrafraction esophageal motion in the right-left (RL) anterior-posterior (AP) directions using computed tomography (CT) cancer patients. Eight patients underwent CT simulation CT-on-rails imaging before after radiotherapy. Interfraction displacement defined as differences between pretreatment images. Intrafraction posttreatment Images were fused bone registries, adjusted carina. mean, average of absolute, range calculated RL AP directions, above below Thirty-one image sets obtained. incidence > or =5 mm 24% =10 3%; 13% 4%. 1.8 +/- 5.1 mm, favoring leftward movement, 0.6 4.8 posterior movement. Average absolute 4.2 less directions. Motion greatest direction Coverage 95% mobility requires 12 left, 8 right, 10 posterior, 9 anterior margins. In all less. These results support a margin for internal target volume (ITV) can guide margins future intensity modulated radiation therapy (IMRT) trials account organ set up error three-dimensional planning.