Basic Treatment Planning

QUANTEC Segmentation Rectum

• The rectum should be segmented from above the anal verge to the turn into the sigmoid colon (this anterior inflection is best appreciated on saggital CT). including the rectal contents.  Although there can be variation in defining these landmarks, the superior limit is where the bowel moves anteriorly, close to the inferior level of the sacroiliac joints, and the inferior limit is commonly at the bottom of the ischial tuberosities.