Indications for nuclear imaging

The scans offered in nuclear medicine are numerous, diverse, and cover all organ systems.  Presently, the most commonly performed studies are FDG PET-CT, myocardial perfusion scans and bone scans.

FDG PET-CT
FDG is fluoro-deoxy glucose (a glucose analog labeled with a radioactive isotope of fluorine, F-18).  Scanning with FDG gives a depiction of glucose metabolism throughout the body.  A majority of malignancies are highly dependent on glucose for energy and avidly pick up this tracer.  This includes such common tumors as lung, breast cancer, and lymphoma. FDG PET-CT has proven highly valuable for diagnosis, the evaluation of treatment response and the monitoring of recurrence.

The images shown are from a PET-CT in a smoker with an indeterminate lung nodule.  The coronal PET image (right) shows intense activity in the right upper lobe corresponding to a nodule demonstrated on the accompanying CT (left).  This indicates the presence of markedly increased glucose metabolism, consistent with (and subsequently biopsy proven to be) lung cancer.  (Also note the intense tracer uptake by the myocardium, since cardiac muscle can utilize glucose for metabolism).