Cancer Treatment Tools
The different imaging technologies each provide different types of information. The CT scan may show the bones the best and have the least geometric distortion but the MRI may give much better soft tissue definition and the PET scan may be the most reliable in separating cancer tissue from normal tissue. Often, the most accurate way to target the cancer and avoid the normal tissue is to scan the patient in the actual treatment position using several different techniques (CT, MRI or PET) and then fuse the images on the treatment planning computer, so that all the information is being used to best target the cancer. This process is called image fusion. It is most reliable when the imaging devices have been equipped with the same type of laser targeting equipment that is mounted on the radiation treatment machines.