One Stop Knee Clinic

What is an MRI?
Magnetic Resonance Imaging (MRI) produces high resolution pictures of any part of the body in any direction. The scanner uses a high-strength magnet, radio waves and computers to generate images. MRI does not use X-rays so it can be used repeatedly. It is considered to be a very safe way of producing images that can diagnose medical conditions.

What to expect
The Radiographer will position you on a comfortable couch, which slides into the scanner. You will be asked to keep still while we scan you and produce your images. The scanner is very noisy when it is taking pictures so we will provide you with ear protection. Examples of the types of noises you may experience during your scan can be heard here.

There are no after-effects from your scan so you can carry on with all your normal activities straight away.

If you have a Buscopan injection, an injection into the joint during your procedure or have taken medications which make you feel relaxed or drowsy it is advised you are accompanied by someone who can drive you home.

How long will it take?
This depends on which part of the body is being scanned. Most scans of one area are completed in 20-30 minutes.

Results
Mr Atwal will receive your scan images and report within 5 working days. You should make an appointment with them to discuss the results. The radiographer will not be able to give you your results on the day of your scan.

What is a CT scan?
The scan is carried out by a special type of x-ray machine. The images the machine produces are cross-sections of your body (think slices in a loaf of bread). The parts of your body can be shown in much greater detail than in standard x-ray films, and this helps the doctors diagnose your condition much more accurately.

You will lie on a moveable bed and pass through the a ‘doughnut’ shaped scanner. A narrow, fan-shaped beam of x-rays is produced from inside the machine, which rotates 360 degrees around you. The x-rays pass through your body and are detected by electronic sensors on the other side of the machine. The information from the machine then passes to a computer which produces a picture of the structure of the inside of your body. The bed moves a small distance to position you for the next picture. It takes about a second to produce each slice. These pictures can then be reconstructed by the computer to form a complete image of the inside of your body.

Risks
CT scanning does involve being exposed to radiation in the form of x-rays, but the benefit of an accurate diagnosis far outweighs the risk from the x-rays. However, if you are pregnant, or may possibly be pregnant, you must tell a member of staff before the scan as unborn children are at greater risk because they are still developing. The amount of radiation used for a CT scan is more than the amount used for a standard x-ray and (depending on the examination you have) is equal to the amount of natural radiation you would receive from the atmosphere over a period of around three years. The CT scan itself is completely painless.

Contrast injections and oral contrasts
A contrast is a dye used to make blood vessels and organs stand out in images. Before the scan, you may have to take oral contrast, have an injection of a contrast, or you may have to have both. If you are breastfeeding you should wait 24 hours after a contrast injection before you breastfeed again.

Can I bring a relative or friend?
If you would like a friend or relative to come with you, they may wait in the waiting room.

At your appointment
When you arrive, please report to reception. Once you have been signed in the radiographer will come and explain the procedure you are going to have. You should tell them if you have diabetes, asthma, or any allergies. If you need an oral (by mouth) contrast the radiographer will give you this before you go to the CT department. If you need to remove any clothing someone will show you to the changing rooms and give you a patient gown or other special clothing to change into.

During the scan you will be made comfortable on the moveable bed. Straps and pillows may be used to help you stay in the correct position and to help you stay still during the scan.

If you need an injection of contrast, you will be given this through a vein in your arm while you are lying on the scanner bed. This may make you feel warm and give you a metallic taste.  The radiographer will stay with you during the injection. The radiographer will control the bed from the control room and will slowly move it to position the part of your body being investigated inside the ‘doughnut.’

The radiographers will be in the control room during the scan, but you will be able to talk to them using an intercom, and they will be watching you all the time. You will hear a clicking and whirring sound from the CT scanner during the procedure. During the scan the radiographer may ask you to hold your breath or to not swallow while each image is being produced – if you feel any discomfort or anxiety because of this, please tell the radiographer immediately.

What are x-rays?
X-Rays are a type of invisible electromagnetic radiation – you don’t feel them when they pass through your body. X-Ray is used in many different ways to diagnose medical conditions. An x-ray image is produced when a small amount of radiation passes through the body and hits a sensitive screen placed on the other side. X-rays are absorbed into tissues and bones in differing amounts. For example, x-raying bone, which does not allow much radiation to pass through it, produces white images, whereas x-raying lungs, which are less dense because they are filled with air, produces darker images.

Risks – what are the side effects?
We are exposed to radiation from the environment every day. Radiation is involved in producing an xray but the dose you will receive is very small – during an x-ray, you will be exposed to around a fifth of the radiation you would receive from the environment over a year. This is similar to the amount of radiation you would be exposed to during a transatlantic flight. You should tell your doctor or radiographer if there is any possibility that you are pregnant – x-rays are a greater risk to unborn children because they are still developing.

Before your appointment
You do not need to make any special preparations for your X-Ray. However, please remove any jewellery that may interfere with the x-ray if you can, for example it would be helpful if you could remove rings for hand x-rays and necklaces for chest x-rays.

The x-ray procedure
The radiographer may ask you to sit, stand or lie on the table depending on which body part is being examined. The radiographer may move you to get the correct position. The radiographer will stand behind a screen while they take the x-ray – although each procedure only produces a small does of radiation, these doses would begin to add up for the radiographer if they had no protection. Once the procedure is complete, you will be asked to wait while the radiographer checks the images. The actual procedure usually only lasts five to 10 minutes.

Can you bring a relative or friend? 
Yes, but for safety reasons they may not be able to go in the x-ray room with you.

The results 
The radiographer will not be able to give you any results on the day. A consultant radiologist will report on the x-ray images and send the report and images to Mr Atwal who will then explain the results to you. In many cases, you may take a CD of the x-ray home with you on the day.