The therapeutic ability of endoscopic ultrasound has expanded, especially in assisting with radiation planning for image guided radiation techniques such as stereotactic body radiation therapy. Endoscopic ultrasound enables precise placement of fiducial markers into pancreatic cancers to accurately delineate the position of the target lesion as it moves with respiration. The authors summarize t...

background: to reduce uncertainties of patient positioning, the computerized tomography (ct) images acquired at the treatment planning time can be compared with those images obtained during radiation dose delivery. this can be followed during dose delivery procedure as image guided radiotherapy (igrt) to verify the prescribed radiation dose delivery to the target as well as to monitor radiation...

CONTEXT Daily setup errors and changes in body habitus during external beam radiotherapy can result in interfraction variation, contributing to uncertainties in treatment delivery. The conventional method of patient positioning using external skin markings is inadequate in reducing these interfraction variations. OBJECTIVE To evaluate use of on-board imaging with daily kV-kV image matching to...

A simple phantom was designed, constructed, tested, and clinically implemented for daily quality assurance (QA) of an ultrasound-image-guided radiation therapy (US-IGRT) system, the Restitu Ultrasound system (Resonant Medical, Montreal, QC). The phantom consists of a high signal echogenic background gel surrounding a low signal hypoechoic egg-shaped target. Daily QA checks involve ultrasound im...

The use of image-guided patient positioning requires fast and reliable Quality Assurance (QA) methods to ensure the megavoltage (MV) treatment beam coincides with the integrated kilovoltage (kV) or volumetric cone-beam CT (CBCT) imaging and guidance systems. Current QA protocol is based on visually observing deviations of certain features in acquired kV in-room treatment images such as markers,...

Background: Based on the radiation biology model of prostate cancer, hypofractionated radiotherapy can improve the treatment outcomes without increasing toxicity. Although hypofractionated radiotherapy is implemented over a short period of time, it is more convenient and cheaper compared with conventional fractionated treatment. The aim of this study was to investigate the early toxicity of mod...