CT and MRI scans
What they are used for, what they can diagnose and how they work.
CT scans
What is a cat scan.• A computed tomography (CT) scan is a kind of like
a x-ray it makes very detailed cross-sectional pictures of your body. It takes pictures of the layers inside your body. It can detect inflammation in your body or can show if you have a bad illness.
What happens before and during the scan• In a CT scan, you lie on a table which slowly
moves through the middle of a big x-ray device. During the scan, the x-ray machine may make soft buzzing, clicking and whirring sounds. Before the scan begins, you might have to swallow dye, or it could be injected into your vein or it given through a tube into your lower intestine. This helps to make the pictures clearer.
MRI scans
What is an MRI scan• An MRI (Magnetic Resonance Imaging) scanner
uses magnetic fields, radio waves and a computer to take pictures of the inside of your body. It takes pictures of a part of your body. An MRI scan is also good because it does not use radiation to take the pictures.
What do MRI scans detect.• MRI scans are really good for finding brain
tumours. This is because they give such detailed pictures. If a tumour shows up then the scan can also be used to see if it has spread into nearby brain tissue. This technique also allows us to look at other details in the brain. For example, it can pick up the different strands in the brain which are a sign of multiple sclerosis. It can also pick up bleeding in the brain, or find out if the brain tissue is lacking oxygen after a stroke has occurred.
BIBLIOGRAPHY• http://science.howstuffworks.com/cat-scan1.htm• http://
www.radiologyinfo.org/en/info.cfm?pg=bodyct • http://
rarediseases.about.com/od/medicaltests/f/ctscan.htm
• http://www.netdoctor.co.uk/health_advice/examinations/mriscan.htm
• http://kidshealth.org/parent/system/medical/cat_scan_abdomen.html
