Computed Tomography (CT Scans)

Computed Tomography is commonly referred to as a CT scan. This technology is very useful when looking at parts of the body such as the lungs and thorax, nasal passage and sinuses, ears, abdomen and some orthopedic structures. CT scans are non-invasive and are not painful. The table on which the animal is laying is slowly advanced into the part of the machine that performs the scan (called the gantry). An x-ray tube rotates 360° around the patient to record the x-rays from many angles, creating slices (or images). The number of images taken depends on the area and size of the suspected problem. When the computer finishes processing the information, the slices are stacked together to create a cross sectional images of your pet without superimposition of organs or other tissues. The University of Minnesota Veterinary Medical Center utilizes a state-of-the-art 64 slice CT scanner. For each rotation of the tube, 64 slices are obtained which results in much faster scanning (often less than 10 seconds) and much thinner slices for excellent detail. After the study has been completed and the patient has left the CT scanner, the information can be used to create other images, including 3D images, for exquisite detail of the internal structures of the patient.

Animals who are candidates for a CT scan include those with lung disease, screening the lungs for metastatic cancer prior to surgery, nasal disease, ear disease, abdominal and some orthopedic conditions and patients with metal implants that cannot be imaged with MRI. CT can also be used to guide tissue sampling of deep structures, particularly within the thorax. CT scans provide better differentiation of bones and soft tissues than conventional radiographs (x-rays) because this slice-based x-ray technology avoids the superimposition of structures that occurs with radiology, and because CT can differentiate between fluid and soft tissue. An iodine-based contrast media is usually injected intravenously to further increase the differentiation of tissue and to evaluate the vessels of the body. The results of the CT scan will help your veterinarian make a more definitive diagnosis and offer you the best options for treating your pet.

CT scans are considered safe, but they do utilize ionizing radiation (like an x-ray). There can be some side effects associated with the iodine-containing contrast which may be injected during the procedure. If your pet has seizures, kidney disease, or cardiac disease, we may elect to use a different type of contrast or not give contrast at all. If CT is used to guide tissue sampling, side effects can include bleeding or a leak of air from lung which leads to air around the lung (pneumothorax).

Pets having a CT scan must be anesthetized or heavily sedated so that they remain still for the procedure, which lasts about 30-40 minutes, including induction of anesthesia, transport, positioning for the procedure, and the actual CT scan. In preparation for general anesthesia or heavy sedation, your pet should not eat after 8:00 pm the night before the exam. Please continue to provide free access to fresh water. Ask your veterinarian for instructions if your pet is on any medications.

We will ask your veterinarian to fax us a copy of the medical record with required bloodwork so that you do not need to be responsible. However, if your veterinarian has any x-rays that they are unable to mail to us in time for the appointment, we ask that you please bring those to the appointment.

Your pet will be anesthetized approximately 30-40 minutes for the CT scan. Before any anesthesia is given, we will make sure that your pet is healthy enough to undergo anesthesia. We will place an intravenous catheter for fluid administration throughout the procedure. In order to place the intravenous catheter safely and in a sterile manner, a small amount of fur will need to be shaved on a leg. Your pet's vital signs will be carefully monitored during and after anesthesia.

After the CT scan, your pet will be disoriented and off balance for about half an hour. We will watch your pet closely until he/she has recovered. Once your pet is standing and able to move around safely, he/she will be hospitalized in our wards. Your pet should be able to be discharged after 3:00 pm. You will be notified as to when you may pick up your pet.

Your pet may urinate a large amount after they get home because of the fluids given during the anesthesia. Once home, it will be important to keep your pet away from stairs and obstacles and feed only a small meal. The effects of general anesthesia should be gone within about 24 hours. If you feel your pet has not fully recovered by that time, please call us or your regular veterinarian.

The radiologist who performed your pet's procedure will complete a report which will be faxed to your referring veterinarian. Your referring veterinarian will call you to discuss the results of this procedure.