ULTRASOUND SCAN
Although ultrasound (US) technology has widely been used in the medical world for diagnosing problems inside the abdomen and monitoring the development of the foetus during pregnancy, it is only more recently that this technology has been used in the evaluation of orthopaedic and musculoskeletal problems. US, unlike Xray, is much better for looking at the soft tissues such as tendons, muscles and various “lumps and bumps”. US can only see the surface of the bones so its use in this respect is limited. US can however be used for assessing a variety of joints to see if there is any build up of fluid or to see if there are any signs of inflammation. US uses high frequency sound waves (not x-rays) to obtain the images and is therefore completely safe. The examination is performed in a scan room and the doctor is able to talk with the patient while the scan is being performed, this enables each examination to be tailored precisely to the needs of the patient. If needed, comparison can be made with a normal area of the body and this enables subtle or very small problems to be diagnosed. US is a “real time” dynamic investigation and muscles and tendons can be observed during movement, this can be useful in assessing how well these structures are functioning. An US examination is very patient friendly and is relatively quick to perform. Although the investigation is a dynamic one and is displayed as it is being performed on a monitor, images are obtained of relevant areas to provide a record of the examination.
MAGNETIC RESONANCE (MR) IMAGING
MRI scans are provided to all our hopitals via a mobile unit. This is the most advanced form of imaging available today and gives unrivalled image quality in respect of the bones, joints and soft tissues. The scan can be used for looking at very tiny structures such as finger tendons or it can be used for looking at a much larger area such as arm or the back. The images are obtained using a very powerful magnet shaped like a tube; the patient lies on the scan table, which then moves into the middle of the magnet. The scans take longer to perform than with US or CT examinations, and as the scanner can be quite noisy patients are given headphones through which they can listen to music. The scan does not involve the use of x-rays. As a strong magnet is used to obtain the images, certain precautions have to be taken; people with pacemakers, certain types of heart valves and people with implanted electronic devices cannot be scanned as these can be affected by the magnet. People with certain types of metal implants (joint replacements) can be scanned but this may have an effect on the image quality. Prior to any MR scan being performed, patients will be asked a comprehensive list of questions to ensure that they are safe to be scanned. As with a CT scan, a huge number of very detailed images are produced all of which have to be analysed before a radiologist can issue a report.
