CONTRAST TOMOGRAPHY (CT)

CT is an advanced imaging tool that allows for incredible detailed studies of the nose, lungs, abdomen and musculoskeletal systems. It can also be used for evaluation of the brain and spinal cord, although typically high field MRI would be recommended for this (see below).

CT can be performed under anaesthesia or we may use a purpose built chamber that can be used to perform the CT without anaesthesia. CT performed without anaesthesia is only used in patients where anaesthesia poses a significant risk as the quality of the images may not be as good due to patient movement.

CT of the brain or spinal cord maybe recommended as CT scans are faster than MRI studies but they may not identify small abnormalities that would be seen with MRI.

All CT studies performed are submitted electronically to specialist radiologists for a report. These reports are received within 1-10 working days.

Our feline clinicians also give an initial report on the day of the procedure.

QUESTIONS AND ANSWERS - CT SCANS

What is a CT scan?

A computed tomography (CT) scan uses x-rays and computer technology to create detailed pictures of the body. It is very fast and can image every type of body structure at once, including bone, blood vessels and soft tissue.
CT scanning equipment consists of a large gantry (a supporting structure) with a circular hole. Inside the gantry is a rotating ring that carries the x-ray machine and x-ray detectors. An attached table slides the cat into the machine.
Multiple x-ray projections are taken in thin slices along your cat's body (like a sliced loaf of bread). The detectors send this information to a special computer that combines them into an image.
The CT scan is also known as a computed axial tomography or ‘CAT’ scan (enter joke here!).

Is a CT scan invasive?

No it isn't. A CT scan is a non-invasive, painless procedure. It is performed with cats under heavy sedation or anaesthesia to keep them still.

Why might a CT be recommended for my cat?

CT scans are commonly recommended for:

Assessment of a body part’s structure or shape
Screening for disease particularly cancer
Diagnosis of trauma or injury
Diagnosis of vascular disease
An aid to planning a difficult surgery
To aid interventional procedures such as biopsy or needle aspiration inside the body.

What happens when a cat has a CT scan?

Generally, the cat is admitted to the hospital either after your initial consultation or on another suitable day.
Your cat will likely have a light sedation given and an intravenous catheter placed. Once the catheter is in place your cat will either be anaesthestised or heavily sedated. This is not because the procedure is painful, it is just because we need your cat to be still and the machine makes a lot of noise.
They are moved to the scanner table and our radiographer may use straps and foam pillows to position their body to help them keep still.
The table slides into the circular hole in the machine.
Depending on the body part and the condition being investigated, a number of images may be taken as the table moves in and out.
The ring inside the gantry moves in a circle around your catas it takes the x-ray images. Each revolution (turning) of the ring takes less than a second and there may be a number of revolutions depending on the examination. This is where ensuring your cat is not moving is very important as movement will blur the images.
Depending on the type of medical investigation, the CT scan may take anywhere from a few minutes to half an hour or more.
Once the CT is completed we will phone you with the results and discuss if any further procedures are required.

Are there any risks associated with the CT scan?

The CT scan is a very safe procedure. Very rarely the contrast agent may trigger an allergic reaction in susceptible patients but this is very rare in cats.

This CT shows a cat with severe pneumonia. The grey part of the lungs is the normal lung. The white area is abnormal. Below this image is an image of normal lungs on CT.