One of the best techniques in imaging nowadays is the PET/CT. Specifically efficient in oncology for tumor diagnosing, defining the percentage of tumor spreading area and radio-therapy planning, this technique can on certain occasions determine the malignant or benign state of the tumor. PET/CT comes from combination of CT (Computerized Tomography), which gives anatomical information in detail; and PET (Poistron Emission Tomography), which gives a view to tissue and organ metabolic function. This instrument can be very helpful for other reasons too. For example, to determine Alzheimer disease which is of neurological nature, also epilepsy, and to point at healthy tissue after the heart attack.