CT Scan stands for Computed Tomography. A CT scan uses X-rays to take detailed pictures of your body from different angles. These are then fed into a computer, which creates a three-dimensional image of your body. A CT scan provides an accurate picture of the internal structures of the body and can show various abnormalities.
CT scans produce detailed images of internal organs, blood vessels and bones. They can be used to diagnose a range of conditions including injuries to internal organs, damage to bones, tumours, problems with blood flow and strokes.
CT scans are normally done as an outpatient in the radiology department of your local hospital, or as a private patient in a specialist clinic. You should allow up to an hour and a half for your appointment. The scan itself will take between 10 and 20 minutes, most of which will be preparation and positioning. Wear loose, comfortable clothes and avoid wearing jewellery and clothing with metal zips and buttons.
During the scan, you normally lie on your back on a couch that passes into the scanner. A ring rotates around a section of your body and you will hear a whirring noise. You will be asked to lie very still while the scan is taken and to breathe normally. At some points you might be asked to breathe in, breathe out or to hold you breath.
Unlike MRI scans which are a tunnel-shape, a CT scanner is a ring or doughnut-shape. It does not enclose your whole body so you shouldn’t feel claustrophobic. A radiographer who will sit in an adjacent room will carry out the scan. You will be able to hear and speak to them via an intercom. The scan is painless but some people may feel some discomfort from having to lie flat if this is difficult for them.
For some CT scans you will need to have a drink or injection of a harmless dye that can help to distinguish different body tissues during the scan. This gives the radiologist a clearer idea of what is going on inside your body.
You will be given precise instructions on how to prepare for your scan beforehand. If you are having a CT colonography, for example, you may be asked not to eat or drink after midnight the night before to allow the radiographer to get a clear look inside your bowel. In some cases, you may be given a drug that slows the normal movement of the bowel.
If you are pregnant we may suggest an alternative study or adjust the CT appropriately to minimise any risks to your baby. We are very happy to discuss any concerns you may have. If you have allergies or kidney problems or if you are taking medication for diabetes, please mention this as your radiographer may need to make special arrangements.
After the scan you can normally leave immediately. Any specific instructions for special scans will be provided as required.
A PET-CT scan combines a PET scan – which uses a mildly radioactive drug to show up areas of your body where the cells are more active then normal – with a CT scan.
A PET-CT scan is normally used to diagnose and monitor cancer, but has other uses too. It is generally more accurate than a PET scan alone. A PET-CT scan can:
- help to diagnose cancer
- determine what stage the cancer is at, whether it has spread to other areas and whether it is operable.
- identify the best treatment for your cancer
- show if your cancer treatment is working and check whether your cancer has come back
You will be advised to stop eating approximately six hours before your scan and to avoid strenuous exercise for 24 hours beforehand.
The scan itself is similar to a CT scan, described above, with similar preparation and aftercare. The difference is that you will be injected with a radioactive drug beforehand. The radiation level is very low and drinking plenty of fluids after the scan will help to flush it out of your system.
This type of scan is safe for most people but let your radiographer know if you are pregnant or breastfeeding or have any concerns.
We offer Interventional Radiology, which is a way of diagnosing and treating disease that requires minimal intervention. An interventional radiologist diagnoses and treats certain conditions through small needle holes, and usually while the patient is awake, which might, otherwise, require surgery.
Image guidance methods such a real time xray (fluoroscopy), ultrasound or CT scans, for example, are combined with a range of approaches including biopsy needles,balloons, catheters, microcatheters, stents and therapeutic embolization to diagnose and treat various conditions
The risk to the patient is lower , and the recovery time quicker than with more invasive procedures.