Since there is not a definitive test for MS, it can be quite difficult to diagnose the disease. The fact that many of the symptoms of MS can be the result of other conditions, makes arriving upon a diagnosis even more complicated. However, if you are experiencing symptoms that may be the result of MS, there are several methods your doctor will use when diagnosing MS to determine whether or not you have the disease. Read on to learn how to diagnose MS.
The criteria used when diagnosing MS
There are three criteria that must be used in diagnosing MS. First of all, your physician must find evidence of damage from the disease in a minimum of two different areas of your central nervous system (CNS). These areas include the brain, optic nerves, and spinal cord. In addition to locating evidence of this damage, your doctor will need to determine that the damage to your CNS took place at different times. Finally, before settling on a diagnosis, your physician will need to consider and rule out any other potential diagnoses.
How to diagnose MS
In order to meet these criteria, there are a variety of tests that your physician will use to determine whether or not you have the disease. Additionally, there are many early signs of MS that you should be on the lookout for.
The first step to diagnosing MS is a thorough physical exam and review of your medical history. During the physical exam, your doctor will most likely look for any issues with nerve and muscle health, as well as any signs of weakness in certain areas, balance problems, uncoordinated eye movements, or issues with vision and speech. Similarly, when reviewing your medical history, your physician will most likely gather information on your family’s health history as well as your own, focusing on any symptoms you have experienced (including when they began, how long they lasted, and if any treatments help improve them).
After going over this information, the following tools and tests may be used by your doctor to settle on an accurate diagnosis.
1. MRI
Magnetic Resonance Imaging, more commonly known as an MRI, or other imaging tests may be used to show your doctor if there are any lesions caused by MS on either your brain or spinal cord. When using an MRI to test for lesions, you may need to receive an intravenous injection that will highlight areas of damage that can tell your doctor whether or not the disease is currently active.
An MRI is widely considered to be “the most sensitive non-invasive way of imaging the brain, spinal cord, or other areas of the body,” and is typically the best imaging resource for diagnosing damage caused by MS.
2. Spinal Tap
Also known as a lumbar puncture, a spinal tap can be a useful test for diagnosing MS. During this procedure, a sample of cerebrospinal fluid (CSF) — a clear liquid surrounding the spinal cord and brain — is taken from the spinal canal for testing. From the sample, a lab can determine if there are any abnormalities within your antibodies that are typical of MS. This test can also help your doctor rule out if an infection or other condition may be causing your symptoms.
The CSF of individuals that have MS oftentimes will contain the below findings, which are indicators that there is an irregular immune response occurring in the CNS
- A specific type of protein known as oligoclonal bands
- Elevated amounts of lgG antibodies
- Specific proteins from the breakdown of myelin (less common)
3. Blood Tests
Blood tests are also a common tool used to rule out any other diseases that may be causing your symptoms. Currently, additional tests are being developed to help labs pinpoint specific biomarkers that are associated with the disease, which may further help doctors in more easily diagnosing MS.
4. Evoked Potential Tests
Evoked Potential, or EP tests, measure your brain’s electrical activity in response to stimulating sensory nerve pathways. These tests can determine if there is any slowing of the electrical conduction to specific nerve pathways due to damage, and can detect damage even if it is too subtle to cause symptoms. There are three main EP tests used in diagnosing MS, including:
Sensory Evoked Potentials
This test involves electrical impulses to the let or arm of the patient
Brainstem Auditory Evoked Potentials
This test uses a series of clicks sent to each ear of the patient
Visual Evoked Potentials
This EP test uses a screen which displays alternating checkerboard patterns to the Patient. This test is considered to be the most useful of the EP tests in diagnosing MS and can be used to show if there is an impaired transmission on the pathways of the optic nerve.
Diagnosing different types of MS
Diagnosing individuals with relapsing-remitting MS is typically much more straightforward than diagnosing those with progressive MS. This is because those with relapsing-remitting MS can usually be diagnosed based on symptom patterns that are typical of the disease and are easily confirmed using imaging tests like MRIs.
However, in individuals displaying symptoms that are less common or those with progressive MS are oftentimes much more difficult to diagnose, and typically involve testing beyond an MRI such as spinal taps, additional imaging, and EP tests.
Revised Guidelines in how to diagnose MS
In 2017 the International Panel on Diagnosis of Multiple Sclerosis published the Revised McDonald Criteria, which provide detailed guidelines for a faster diagnosis of MS using an MRI or a spinal tap. The report noted that an MRI is an effective way to identify a second damaged area in individuals that have only had one MS attack. It additionally confirmed that an MRI can be used in some cases to confirm that the timing of damage occurred at two different periods of time. The study also stated that when it comes to spinal taps, the presence of proteins known as oligoclonal bands can confirm an MS diagnosis in certain circumstances.
The process of diagnosing MS can be long and frustrating, and may not happen for months, or even years, after your first symptoms. Once you have finally been diagnosed it is important to surround yourself with a strong support system including friends, family, counselors, and, of course, your doctor, as you figure out the best way to treat and live with MS.
