What is an MRI scan?
Updated: Apr 27, 2021
What is an MRI:
An MRI is highly advanced medical tool that can be very useful in acute (sudden onset) injuries, like a broken leg, or in cases when malignancy (cancerous tumour), or other systemic diseases are highly suspected. In those situations, I believe the MRI is a modern miracle and one for which we truly can be grateful. We are very lucky to have the ability to detect cancer in time to save lives. However, their usefulness as pain persists (lasting more than 3 months) decreases significantly, adding little to rehabilitation planning, and arguably can make the situation worse, by amplifying the pain experience, and increasing disability . When we are unsure or apprehensive to move our bodies because we have heard terms describing our body structures like “degeneration”, “wear and tear” and “abnormalities” or hear unfounded projections like “it will get worse” or “you have the back of an 80 year old”, pain can be amplified. The implication that your current state is unchangeable due to what is shown on a scan, can leave many feeling pretty rotten and pretty hopeless about your situation. However, I’m here to share more information about why this is not only incomplete information, but also inaccurate and does not have to have a stronghold over your future. The truth is that tissue state is not always a predictor of present pain, nor is it a predictor of future tissue state or future pain, and you should never be told otherwise.
How does it work and what do you see?
An MRI works by rotating a magnet around your body. The MRI uses magnetic fields, radio waves and a computer to form detailed images of the structures in the body. In the low-back (lumbar spine) area an MRI can show vertebrae (spinal bones), discs, spinal cord, and the spaces in between the bones where the nerves pass through.
During the scan, you are required to lay very still in a large metal tube in order for the images to be created clearly. Any movement, including bowel movements or breathing, can affect the quality of the image. Sometimes while the image is being taken the practitioner may ask you to hold your breath for a period of time. An MRI can be very uncomfortable since you are required to move very little and be in the same position for up to 90 minutes.
The biggest difference between an MRI and an X-ray is that an MRI does not use radiation and therefore takes away exposure risks. This can make it a safer option when considering what kind of scan you might need.
Who is it for?
There are a few reasons why you might need an MRI scan. The most pressing reason being that there is a suspected malignancy. If your doctor or physiotherapist notices symptoms that seems out of the ordinary or possibly life-threatening, you will likely be sent for an MRI. However, keep in mind that most Western medical systems over prescribe MRIs and send many people for scans who have no signs or symptoms of something life-threatening . Just because you are sent for a scan does not mean you may have a tumour, but if this is something you are concerned about you should discuss this with your doctor.
An MRI is also often done when conservative treatments (non-invasive treatment ie. exercises, physio, chiropractic etc..) have been attempted with no success, or if you develop new symptoms during the course of treatment. In these cases it is mostly done to rule out other more systemic potential causes of pain.
Why should you get one?
Unless there is a traumatic acute injury (in the last 6 weeks) that might need surgery or suspicion of other more medically serious pathologies, having a scan, will likely not change the course of your rehabilitation plan . An MRI could however have beneficial effects if it does reassure you that something more serious is not going on and helps you feel safe to move again.
Generally your doctor will decide if you need an MRI. This is not something that you should have to worry about. However, if you are concerned and feel as if you want one, but your not being scheduled to have one, it is recommended that you discuss this with doctor or physiotherapist. A discussion may help you to better understand why your doctor/therapist has not recommended a scan at this time.
Reasons why an MRI might not be safe for you:
Although generally very safe, there are some reasons specific to the individual that may indicate that an MRI is not a safe or appropriate choice for you.
- Metal in the body
- 1st trimester pregnancy/ or breastfeeding
- allergy to dye
- other implants: like cochlear, or pacemaker
- tattoo with metal in the ink
- Claustrophobia (you will need to lay very still in a narrow metal tube for up to 90 minutes)
Aside from physical health risks there are also psychological health risks to getting an MRI. Some of which I mentioned above and will continue to discuss further in the section about scans and pain down below.
In an ideal world, your health care professional would sit down with you to help you interpret and understand your MRI, but let’s be honest, how often does that happen? Many health care providers are just too busy, and simply do not have the time to sit with you and help you make sense of your scan and what it means in the context of your life and goals. And if they do have time, often it will be described in a way that is equally as scary and confusing as the written document. Many times, in physiotherapy or other allied health professions, it is assumed that these conversations have already taken place and will not be had at all. This is unfortunate, and the person that suffers most, is you. Which is why I created this document. I created this document for you. To help you get more reliable, evidence-based information into your hands. Because when you are informed, you have the power to make better, more educated decisions about your own health and care.
What is informed consent?
Specifically in healthcare, informed consent is a term used to describe when a patient (you) gives permission or consent for a scan/intervention/treatment only after they have been fully informed about the possible risk and benefits that that intervention could have. There needs to be a dialogue happening between you and your healthcare provider that very clearly discusses the benefits and the risks of whatever treatment you are seeking to have. Only after this conversation has taken place should you be making a decision (in collaboration with your healthcare provider) about any kind of intervention especially one that is invasive like a surgery.
Informed consent should also take place before an MRI scan. It’s important to understand why you are getting scanned and what the implications of that scan are. When we are sick, in pain and worried about our health we are in a vulnerable state. We can easily feel dependant on our healthcare provider to take care of us and let us know what is best. Although it is the job of the healthcare provider to show you options and have recommendations, you always have a say. It’s your body and your health. As much as healthcare providers study and have knowledge, we can never say with 100% certainty what is going to help you. There are always potential risks and potential benefits no matter what course of action taken. It is therefore important that you are aware of what these potential benefits/risks are and that you are involved in the decision making process.
What if I don’t feel informed?
If you feel that you are not being informed properly yet are having to make an important decision regarding your health, please speak up and ask more questions. If you are not sure what to ask, start with asking “what are the risks and benefits of this?”. It is the job of the healthcare provider to explain to you what the options are and you are not expected to have any prior understanding of these procedures. And if you do, it’s always good to check that your understanding is correct, before making any big decisions about the kind of health care you receive.
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