Image fusion using CT, PET, MRI and nuclear medicine
CT, PET, MRI, and nuclear medicine are four distinct technologies that generate images of the internal structures and organs of a patient. These four technologies yield complementary information about the location, physiology and physical properties of diseased or injured tissue and the surrounding healthy organs.

CT reveals bones very well, which help in positioning the patient. CT also generates physical data necessary for calculation of suitable radiation dosage. Physicians delineate certain types of tumors and some healthy tissues on a CT scan, but sometimes rely on MRI or PET to evaluate other types of tumors or organs. MRI helps with soft-tissue visualization, while PET can locate regions where sugar is being preferentially metabolized, such as in tumors.

CT, MRI, PET and other imaging devices can quickly acquire 3D images, which can be further computed to merge into a single volume that combines the information from all modalities. Using all that consolidated information enables the most informed, advanced planning for precisely where and how radiation dosages should be delivered.