Nuclear scintigraphy, or scanning, is a form of diagnostic imaging designed to detect areas of increased bone metabolism that may signal orthopedic diseases. It is especially helpful in identifying multiple areas in the skeletal system that may be contributing to lameness. Bone scans enable veterinarians at the Hospital for Large Animals at Cummings Veterinary Medical Center at Tufts to look at regions of the body, such as the back, pelvis and hips of the horse, that are inaccessible to other imaging modalities.
During the procedure a patient is injected with a radioactive dye (radioisotope) that accumulates around inflamed bones. After the injection, the horse is placed in a stall for a few hours to allow the isotope to settle into the affected areas. The horse is then scanned with a gamma camera, which is similar to a large Geiger counter. The gamma camera detects the isotope signal as it emanates from the horse and produces an image that highlights specific areas of inflammation. From these images, the clinician is able to determine the affected areas and narrow down the potential causes of lameness.