Medical Imaging: What Types and When Is It Useful?
With the recent episode of the Physical Performance Show featuring Dr Hal Rice from Q-Scan I thought it would be a nice opportunity to outline in writing the common imaging types that may be used in your presentation.
Medical Imaging plays a very important role in modern medical science especially musculoskeletal issues such as those commonly treated by a physiotherapist.
Medical Imaging plays a very important role in modern medical science especially musculoskeletal issues #performbetter @pogophysio Click To TweetThe most common types of Medical Imaging Are:
Plain Film X-RAY:
The oldest form of medical imaging involves a small dosage of electromagnetic radiation passed through the body. This radiation is absorbed differently by types of body tissue, hence an image is able to be produced.
X-RAY is particularly useful when imaging bones and checking for fractures, growths, joint space or cancers but can also be useful in assessing lungs and other areas of the body.
These scans are cheap and easy to perform but give only a flat 2D image of bone and minimal information on soft tissues.
CT:
CT stands for computed tomography and is the process of building a 3D image out of many X-RAYS taken from multiple angles. Because a CT is able to build a 3D image it is much more useful in assessing the body for any foreign growths, a more detailed description of bone structure and more information on any swelling present.
CT scans are more expensive but also contain much higher doses of radiation which means that the amount of CT scans you should have in your life should be minimised.
CT scans for physiotherapists are particularly useful in diagnosing stress fractures or smaller fractures in bones such as the navicular or scaphoid.
MRI:
MRI stands for magnetic resonance imaging and is a type of imaging technique that does not use radiation, and instead uses magnetic fields to assess body tissues. MRI builds a 3D image and is excellent at assessing soft tissues throughout the body.
MRI’s are particularly useful for physiotherapists in bone stress injuries, ligamentous or cartilage injuries, muscle or tendon unit injuries, nerve injuries, spinal injuries ect.
MRI is unfortunately more expensive and harder to perform however it’s advantages are often too important hence it’s importance in modern medicine continues to grow.
Diagnostic Ultrasound:
Ultrasound is a common imaging technique most associated with pregnancy however it also has an important role in musculoskeletal imaging.
Ultrasound uses high frequency sound waves emitted into the body that rebounds back to the receiver and gives a live picture of the body. It is great at assessing muscle, tendon, bursae, cysts and fluid but sometimes not accurate and not very good at assessing deep intra-articular structures such as cruciate ligaments.
Ultrasound can be excellent at guiding live injections into painful structures of the body or even assessing structures dynamically as your body moves.
In physiotherapy ultrasound is often used for assessing tendon tears, bursal pathologies and ligamentous injury.
Ultrasound is usually a cheaper option than MRI however not as accurate, it can be a good option to take if the injury is superficial and easier to see on an ultrasound.
Medical Imaging is one of the fastest developing fields of medicine however it still has it’s limitations.
Medical Imaging should never be relied upon solely, this is because as we are getting better at imaging, we often find things that are ‘wrong’ or ‘different’ with body parts that are not necessarily causing any problems for the person. This means that the information from your scan should always be thoughtfully and critically ‘married’ up to your history and physical examination. In most musculoskeletal issues, medical imaging should only be used to confirm or rule out the presence of a pathology after a clinical diagnosis has been made.
So in conclusion there are a few things you need to remember:
- Medical Imaging plays a pivotal role when required in adding the final piece of information when assessing and monitoring musculoskeletal issues
- It is excellent at excluding sinister or more serious pathology
- Your physiotherapist will know what type of imaging to use and when it is necessary
Hopefully you don’t need any medical imaging any time soon!
Michael Harders
Master Physiotherapist
Featured in the Top 50 Physical Therapy Blog
