Multiple sclerosis (MS) diagnosis is extremely difficult. The reasons for this include:
- More than 50 symptoms are linked to MS, and each person develops symptoms differently.
- Many of the symptoms mimic problems that occur with other diseases.
- There is no blood test for MS yet.
- Symptoms usually come and go.
- Many symptoms are vague and hard to quantify, such as fatigue, sexual dysfunction, depression and cognitive difficulties. These often get attributed to stress by general practitioners, and patients may never be referred to a neurologist.
In my case, the neurologist that finally diagnosed me estimated that — based on things that he saw on my MRI — I had MS for at least 15 years before my diagnosis. Sure enough, I could think back that many years to a series of tremors, sensory symptoms and cognitive clues which took me to many doctors (including some neurologists), but never resulted in a Multiple Sclerosis diagnosis.
Things are improving on this front because of the increased use of MRIs, which allow neurologists and radiologists to actually take a look at the brain and spinal cord for characteristic MS lesions. However, MS is still a very tricky disease to definitively diagnose, and the process may require patience.
It is important to find a neurologist that you feel comfortable with and have confidence in to work on your diagnosis. After all, if you do have MS, this person will likely be your partner in health for a long time.
Multiple Sclerosis diagnosis Tests and Procedures
Magnetic Resonance Imaging (MRI) Scan
MRIs use magnetic waves to produce images of the brain and spinal cord. If MS is suspected, a special contrast material (gadolinium) injection is usually at the time of the scan, as it reacts to areas of inflammation and will “light up” when a lesion is active. This indicates that demyelination is occurring.
The MRI does not hurt, but it can be a strange experience. It helps if you know what to expect during this test. There are also some things you can do to make your experience better.
As mentioned, this is considered the best test for diagnosing MS, as abnormal lesions appear on MRIs in over 95% of people with MS. However, 5% of people with MS do not have abnormalities that can be detected on an MRI (producing a false negative), and some age-related damage looks like MS lesions (producing a false positive).
The doctor will ask a number of questions about the symptoms that you are currently experiencing and any that you have experienced in the past. It is a good idea to make a “symptom log” before you see the doctor, listing any sort of symptom that you have had in the past, how long it lasted and other information about it.
List all symptoms, even if other doctors told you there was nothing wrong. In addition, take all other medical information along, including which prescription drugs you are on, any medical test results you may have and other doctors’ findings.
You will also be asked several questions about the medical history of relatives, drug and alcohol use, as well as other health issues that you may have had in the past. All of this information will help a neurologist piece together a picture to help determine if Multiple Sclerosis diagnosis is a likely diagnosis.
Multiple Sclerosis diagnosis Neurologic Exam
The doctor will be testing for the following:
- The functioning of the cranial nerves (these control the senses, as well as how you talk and swallow)
He will do this by having you perform tasks (like touching your nose, then his finger in succession), touching you with various instruments (and having you report a sensation or looking for a response himself) and doing an examination of your eyes. These tests do not hurt. The entire test will probably last about 45 minutes, but maybe as long as two hours.
Evoked Potential Testing
Three main types of evoked potential tests are used in the diagnosis of MS. Each of these tests requires that electrodes are attached to your scalp and connected to an electroencephalograph (EEG) to record brainwaves in response to different stimuli. The different tests are:
- Brainstem Auditory Evoked Potentials (BAEP): A series of clicks are played in each ear through headphones.
- Visual Evoked Potentials (VEP): A series of checkerboard patterns are displayed on a screen.
- Sensory Evoked Potentials (SEP): Mild electrical shocks are administered to an arm or leg.
The doctor is looking for both the size of the response and the speed in which the brain receives the signal. Weaker or slow signals may indicate that demyelination has occurred and that MS is a possibility.
However, this test is also not specific to MS; abnormalities could indicate another problem. A series of all three tests could take up to two hours to complete.
Also called a spinal tap, this test requires that a small amount of cerebrospinal fluid (CSF) be taken from your spinal column via a needle that is inserted between your vertebrae. The doctor will send the fluid for evaluation, looking for the presence of oligoclonal bands (an increased number of certain antibodies) — an indicator of increased immune activity in the spinal fluid.
This test is positive in up to 90% of people with MS, but is not specific to MS; a positive result could indicate another disease or disorder. Depending on results from the MRI, neurologic exam and symptom history, it is possible that you may not have to get a lumbar puncture to receive a definitive diagnosis of MS. (I didn’t.)
However, lumbar puncture results can be useful for ruling out other things if there is still a question about diagnosis.
An important note: Lumbar punctures can be done using an x-ray technique known as fluoroscopy, which helps the doctor or technician guide the needle. Lumbar punctures done this way are usually faster and less stressful. However, many people (such as residents, interns and less experienced doctors) are anxious to perform lumbar punctures without fluoroscopy, so that they can get the practice. Do not hesitate to insist on getting a fluoroscopy-guided lumbar puncture, even if you have to get referred to another facility for the test.
There is currently no blood test for MS, although scientists are working on this, so there may be one in the near future. Still, a series of tests will be run on your blood to rule out other things, such as Lyme disease, HIV, some rare genetic disorders and a group of diseases known as collagen-vascular diseases (these include lupus, rheumatoid arthritis, scleroderma and others).
Multiple Sclerosis diagnosis Criteria
There are two basic rules for Multiple Sclerosis diagnosis(MS):
- The person must have had at least two relapses (an episode where symptoms were present). These episodes must have been separated by at least one month.
- There must be more than one lesion on the brain or spinal cord.
Multiple sclerosis means just that — multiple (more than one), sclerosis (areas of damage; scarring or hardening).
- Negative: Negative means negative. You don’t have MS. It is possible for the doctor to give this diagnosis only when another definite diagnosis is made that can account for your symptoms.
- Possible: This means that you may have symptoms that look like MS, but your tests are normal. No other diagnosis which accounts for the symptoms has been confirmed.
- Probable: Many people fall into this category when they are first seen by a neurologist. You may have symptoms that look like MS and have had two separate episodes separated by at least a month, but normal findings on an MRI. You could also have an MRI that showed only one lesion in your brain or spine. In this case, your doctor will probably recommend repeating the MRI after a certain period of time (for instance, 3 months) to see if any other lesions appear. Depending on how certain your doctor is that you really do have MS, he may recommend that you consider starting an early therapy.
- Definite: Your case fits the diagnostic criteria above. You have had at least two attacks, separated in time, plus at least two areas of demyelination. Believe it or not, many people are relieved to receive a definite diagnosis of MS. I was. I knew what was wrong with me and I knew what I had to do next, rather than continuing to wonder what was causing my problems and worrying that it was something that I was doing.