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Slide courtesy of U. van der Heide
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Question 2: inter- and intrafraction mobility
MRI is particularly useful to measure motion variability due to its excellent soft
tissue visualization, the absence of radiation, the availability of multiplanar
imaging and fast 4D imaging. Using serial MRIs during external beam
radiation for cervical cancer demonstrates that the uterus, cervix, vagina
and even pelvic lymph nodes have considerable motion between treatments
due to changes in bladder filling, rectal filling and other internal motion.