Positron emission tomography (PET) scans are advanced imaging tests that offer a detailed look into the metabolic activity within your pet’s tissues and organs. Much like in human medicine, a PET scan for your pet utilizes a radioactive tracer to highlight both normal and abnormal biological functions. This powerful diagnostic tool can often detect diseases at their earliest stages, sometimes even before they become visible on standard imaging tests like X-rays, CT scans, or MRIs.
During a pet PET scan, your animal will be carefully positioned, usually under sedation or anesthesia to ensure they remain still, on a specialized table that gently slides into the PET scanner. The scanner then works to create detailed images reflecting the metabolic activity throughout your pet’s body. This process typically takes around 30 to 60 minutes.
How Does Pet Positron Emission Tomography Work?
A pet PET scan relies on a special radioactive substance called a tracer, which is usually administered through an injection. This tracer is designed to accumulate in areas of the body where there is heightened metabolic or biochemical activity, which is often indicative of disease processes. Think of it as highlighting areas of increased activity within your pet’s body at a cellular level.
The images generated by the PET scan are frequently combined with those from a CT (computed tomography) or MRI (magnetic resonance imaging) scan. This fusion creates what’s known as a PET-CT or PET-MRI scan, providing a more complete and detailed picture for veterinarians to interpret.
Why is a Pet PET Scan Performed?
Pet PET scans are invaluable tools for diagnosing and managing a wide range of conditions affecting animals, including cancer, heart problems, and neurological disorders. Veterinarians utilize the information from PET scans to:
Cancer Detection and Management in Pets
Cancer cells often exhibit a higher metabolic rate compared to normal cells, causing them to appear as bright spots on PET scans. In veterinary oncology, PET scans can be crucial for:
- Early Cancer Detection: Identifying tumors and cancerous growths, sometimes before they are detectable by other methods.
- Staging Cancer: Determining if and where cancer has spread (metastasized) within your pet’s body.
- Monitoring Treatment Effectiveness: Assessing how well cancer treatments like chemotherapy or radiation therapy are working.
- Detecting Cancer Recurrence: Identifying if cancer has returned after treatment.
It’s important to note that while PET scans are powerful, interpretation requires expertise. Some non-cancerous conditions can also show increased metabolic activity. Moreover, not all types of cancer are detectable by PET scans. However, many solid tumors commonly found in pets can be effectively assessed using PET-CT and PET-MRI, including cancers affecting the:
- Brain
- Breast (Mammary Glands)
- Cervix (in females)
- Colon and Rectum
- Esophagus
- Head and Neck
- Lungs
- Lymph Nodes (Lymphoma)
- Pancreas
- Prostate (in males)
- Skin (Melanoma, etc.)
- Thyroid
Heart Disease Evaluation in Pets
PET scans can also play a role in evaluating heart conditions in pets. They can reveal areas of reduced blood flow to the heart muscle. This information can be vital in deciding the best course of action, such as whether a pet might benefit from surgery or other interventions to improve blood flow.
Neurological Disorders in Pets
In veterinary neurology, PET scans can be used to investigate various brain disorders, including brain tumors and seizure disorders. They can help assess brain activity and identify abnormalities that might be causing neurological symptoms in your pet. While Alzheimer’s disease as in humans is not directly applicable to pets, PET scans can assist in evaluating cognitive dysfunction syndrome and other age-related brain changes in older animals.
Are There Risks Associated with Pet PET Scans?
For a pet PET scan, the radioactive tracer is administered in a very small dose. Consequently, the risk of adverse effects from radiation exposure is considered minimal. However, it’s worth being aware of potential, though rare, risks:
- Radiation Exposure: While low, there is some radiation exposure from the tracer. The benefits of diagnosis typically outweigh this minimal risk.
- Allergic Reactions: Allergic reactions to the tracer are rare but possible.
- Effects on Pregnancy/Nursing: This is less relevant for typical pet scenarios but important to discuss with your vet if your pet is a breeding animal.
Always discuss any concerns you have about the risks and benefits of a PET scan with your veterinarian.
Preparing Your Pet for a PET Scan
Your veterinarian will provide specific instructions on how to prepare your pet for their PET scan. General guidelines often include:
- Fasting: Typically, food is withheld for a few hours before the scan, often around 4 hours, as indicated in the original article.
- Informing your Vet: Tell your veterinarian about any pre-existing conditions your pet has, especially diabetes or kidney issues, and any medications or supplements your pet is taking.
- Calm Environment: Minimize stress for your pet before the procedure.
- Sedation/Anesthesia: As pets need to remain perfectly still during the scan, sedation or general anesthesia is usually necessary. Your vet will discuss the safest and most appropriate option for your pet.
What to Expect During Your Pet’s PET Scan
The PET-CT or PET-MRI scanner used for pets resembles the human versions, a large, doughnut-shaped machine. The process generally takes a couple of hours from start to finish, including preparation and scan time.
Upon arrival, you may be asked to confirm fasting status and discuss any last-minute concerns. A veterinary technician or assistant will administer the tracer injection. There is usually a waiting period of 30 to 60 minutes to allow the tracer to distribute throughout your pet’s body.
During the scan itself, your pet will be carefully positioned and monitored while the scanner takes images. The scanner may produce buzzing or clicking sounds, which are normal. The scan duration is typically around 30 minutes for a PET-CT and slightly longer for a PET-MRI. Throughout the procedure, your pet will be under the close supervision of veterinary professionals.
Understanding the Results of Your Pet’s PET Scan
A veterinary radiologist, a specialist trained in interpreting imaging studies, will analyze your pet’s PET scan images. They will then provide a report of their findings to your primary veterinarian.
The radiologist may compare the PET scan images with any previous imaging studies your pet has had, such as X-rays or ultrasounds, to gain a comprehensive understanding of your pet’s condition. The combined information from PET-CT or PET-MRI scans offers a detailed diagnostic assessment to guide the best treatment plan for your beloved animal.
References:
- Positron emission tomography — Computed tomography (PET/CT). Radiological Society of North America. https://www.radiologyinfo.org/en/info.cfm?pg=PET. Accessed April 6, 2021.
- What is PET? Society of Nuclear Medicine and Molecular Imaging. https://www.snmmi.org/AboutSNMMI/Content.aspx?ItemNumber=5649. Accessed April 6, 2021.
- Umterrainer M, et al. Recent advances of PET imaging in clinical radiation oncology. Radiation Oncology. 2020; doi:10.1186/s13014-020-01519-1.
- Adam A, et al., eds. Adrenal imaging. In: Grainger and Allison’s Diagnostic Radiology. 7th ed. Elsevier; 2021. https://www.clinicalkey.com. Accessed April 6, 2021.
- ACR-SPR practice parameters for performing FDG-PET/CT in oncology. American College of Radiology. https://www.acr.org/Clinical-Resources/Practice-Parameters-and-Technical-Standards/Practice-Parameters-by-Modality. Accessed April 6, 2021.
- Cervical cancer. Radiological Society of North America. https://www.radiologyinfo.org/en/info.cfm?pg=cervicalcancer. Accessed April 8, 2021.
- Morrow ES. Allscripts EPSi. Mayo Clinic. April 6, 2021.
- Collins DA (expert opinion). Mayo Clinic. April 24, 2021.
