Abstract
Pancreatic scanning has been subjected to more modifications than any other nuclear medicine procedure, yet it continues to be a challenge for most nuclear medicine departments with standard instrumentation. Our method enables us to obtain consistently reliable images of high quality in routine pancreatic scanning, using a rectilinear scanner. The lowest activity area in the abdomen—the coldspot—is chosen as the scanner setup point. The light source voltage is adjusted so that coldspot is just above the lower knee (light grey) of the density curve. The selected range differential must vary with coldspot percentage of scale to achieve an equivalent of 40% suppression. These setup factors ensure high contrast and controlled background sensitivity for all pancreatic scans using a rectilinear scanner. Better enhancement of image quality is achieved by use of two overlapping films in the cassette to record the photo scans with scanning done at double speed and half-line spacing, which results in averaging of density fluctuations due to random counting rate. The second film with its filtered image gives better anatomic definition of pancreas and liver. The routine pancreatic study includes scanning at 10 min and 40 min after injection of Se-75; a Tc-99m sulfur colloid liver scan is done while the patient is in the same position.
