CT AND MRI SCANS Year 9 Nervous System Assignment Eden Hughes-Barbour – 9 Bronze

CAT - What are they used for? The CAT scanner was originally designed to take pictures of the brain. It is much more advanced now and it is used for taking pictures of almost any body part.

What can they diagnose? A CAT scanner is particularly good at testing for bleeding in the brain, aneurysms (when an artery swells up), brain tumours and brain damage. It is also used to find tumours and abscesses throughout the body and is used to assess types of lung disease.

How patients are prepared and photographed? For example; If the patient needs an abdomen scan, it will be asked of them not to eat for six hours before the scan. 45 minutes before the procedure, the patient will be given a drink containing ‘Gastrografin’, an aniseed flavoured X-ray die which makes the intestines easier to see on the pictures.

How they work? During the scan the patient will lie on the bed, with the body part that is under examination placed in a round tunnel or the opening of the scanner. The bed will then slowly move forward and backwards so that the scanner can take pictures of the body. The scanner does not touch the patient at any time of the scan. The length of the test will vary on how many pictures need to be taken and the different angles for the picture.

MRI – What are they used for? An MRI scan is used for medical imaging. It uses a magnetic field and radio waves to take pictures of inside the body. It is very helpful to collect pictures of soft tissue such as organs and muscles that don’t show up on x-rays.

What can they diagnose? MRI scans can diagnose tumours, soft tissue and bone conditions, cysts, abnormalities of the brain, spinal cord, it can show if a tumour has spread to near by tissue, it can also look at soft parts of the body including you liver, spleen and kidneys.

How patients are prepared and photographed? To prepare for a MRI scan you can do pretty much everything as normal, take your normal medication (if you need to) and eat as usual (unless your doctor tells you otherwise). The only thing you need to do is remove all metallic objects and leave them outside of the scanning room, including hearing aids, dentures and prosthetic devices. You can not take in any credit cards since the magnetic codes on them can be affected by the magnet. If you are receiving a head scan, all make up must be removed because it may contain metallic powders which are magnetic and might degrade the image quality. You might also be asked to wear a hospital gown since clothes may have metallic fasteners or metallic fibers that can interfere with the image.

How they work? The patient will lie inside a large shaped magnet. Radio waves are then sent through the body. The scanner will pick up signals and they will be sent to a computer that turns them into pictures. The pictures are based on the location and strengths of the incoming signals.

Bibliography ns/ctgeneral.htm ns/mriscan.htm