What is a CT scan?
An CT scan is a detailed 3D scan of a part of the body. CT stands for computed tomography. It uses X-rays which are a vey strong form a light that cannot be seen. This light goes under the skin and through the body. Different tissues stop the X-rays from getting through the body by different amounts. Bone stops most of the X-rays from getting through, whereas lung is mainly filled with air and stops very little X-ray from getting through. A computer uses the information about the strength of the X-ray that gets through the body to create a series of detailed black-and-white ‘slices’ of the body.
It is mainly used to see the bones in 3D, however CT scans also give important information about the soft tissues, such as the quality of muscles around your shoulder. Mr. Davies particularly uses CT scans to help in the planning stage of a shoulder replacement and also to assess fractures in more detail.
How is an CT scan performed?
You are asked to lie on your back on a table. This table moves into the CT scanner itself. The scanner looks like a doughnut and the table moves into the hole in the middle. You will hear a faint whirring sound as the scan is taken, which takes around 5-10 minutes. You need to keep as still as possible during the scan. As soon as the scan is finished, you can leave.
Are CT scans safe?
The form of light that CT scans use is called ionising radiation. Put simply, ionising radiation can damage your DNA. At its most extreme, this could cause cancer, in exactly the same way that too much sunlight can cause skin cancer. However, the dose of radiation is very low for CT scans so your personal risk of developing any sort of cancer from a single scan is very low indeed..
So, in summary, YES, CT scans are safe!
How soon will I get the result?
The result is usually immediately available and is sent to the doctor’s computer. A formal report from a radiologist is usually sent within a few days. Mr. Davies is happy to show you your CT scan and describe the areas that he is looking at.