We are thrilled to have gotten a state-of-the-art Gamma camera that will allow us to perform many new studies that were not possible previously. We are the first pet hospital in the USA to purchase a Syngula Scintron from MiE and we are very excited about the potential that this new machine will bring us.
Nuclear scintigraphy is a common imaging modality used in human medicine, its application in veterinary medicine is still considered limited. Few facilities have the capability to offer this service, which is typically reserved for Universities. We are one of a few Specialty Hospitals in the USA to have this capability.
Nuclear scintigraphy uses very small amounts of radioactive compounds attached to drugs that travel to a specific organ or tissue and the emitted gamma radiation is captured by the gamma camera. This allows us to use physiology to diagnose diseases for instance.
Thyroid scintigraphy is very helpful not only to diagnose hyperthyroidism, but also to help rule out a thyroid carcinoma as well as to aid in the I-131 dosing protocol.
Bone scintigraphy can be used to help diagnose lameness for an unexplained reason by localizing the lesion. It may also help to localize bone metastasis as well.
Pulmonary perfusion (thromboembolism)
Pulmonary study to identify pulmonary thromboembolism. This is a quick and non-invasive way of identifying pulmonary thromboembolism in dogs and cats. The radionuclide is injected intravenously. Because of its predilection for the lungs, it accumulates in the pulmonary tissue. However, it will be impossible for the radionuclide to accumulate in the lungs if a clot were to be present in the lungs. This would present itself as a void (lack of contrast uptake) in areas of the lungs.
Glomerular filtration rate (GFR)
It is used to evaluate kidney function. Nuclear scintigraphy when determining individual kidney function is important. If a kidney mass is found and the clinician is trying to predict the likelihood that the patient will develop kidney disease post kidney removal.
Normal kidney function
Early kidney disease (more pronounced on the left kidney)
Moderate chronic kidney disease (more pronounced on the left kidney)
Portosystemic shunt scintigraphy
This is a great tool to rule out a portosystemic shunt, especially when there is a low suspicion of a shunt. Abdominal ultrasound has an approximate 70% sensitivity in finding portosystemic shunts. Therefore, not identifying a portosystemic shunt on ultrasound does not rule it out and it would prompt the recommendation of either an abdominal CTA (computed tomography angiogram) or nuclear scintigraphy. Nuclear scintigraphy can be done quicker, it is cheaper, and does not require anesthesia.
In the absence of a portosystemic shunt, the radionuclide will accumulate in the liver instead of going to the systemic circulation.
The radionuclide is injected directly into the spleen. The blood flow will take the radionuclide to the liver or the heart depending on the absence or presence of a portosystemic shunt respectively.
In the presence of a portosystemic shunt, the radionuclide will travel to the heart, then lungs, back to the heart, and then the systemic circulation.
A composite image of all the frames shows the accumulation of radioactivity in the thorax. No accumulation is noted in the liver since the blood from the spleen bypassed the liver to go to the heart.
Biliary outflow scintigraphy
Biliary outflow obstruction can occasionally be challenging to diagnose. Tc99-mebrofenin is excreted via the bile. Therefore, it should appear in the duodenum after injection as shown below. The absence of Tc99-mebrofenin excretion into the duodenum is supportive of biliary obstruction.
Other applications of nuclear scintigraphy
Gastrointestinal motility scintigraphy
Scintigraphic imaging of inflammation
Receptor, monoclonal antibody, and peptide imaging
Future applications in veterinary medicine may include targeted therapy for metastatic tumors, for instance.
For more information
Book an appointment with Dr. Galvao or Dr. Otoni in the Nuclear Medicine Department.
Please ask to speak to Jenny Day (Internal Medicine Care Coordinator)