Because it’s a degenerative autoimmune disease, multiple sclerosis is not something to be taken lightly, and it’s important to know for certain that this is the disease that’s causing problems in the body. In fact, because other ailments that could mimic the symptoms are just as important to treat, it’s crucial to get a definitive answer.
Fortunately, more and more tools to help doctors identify markers of and diagnose MS are available all the time. The need to rule out any other possibilities prior to making a diagnosis, as well as to be clear with sufficient evidence of the presence of MS means that there is quite a bit of time and research involved, taking into account several factors. An evoked potential test is just one of many options at the doctor’s disposal.
The importance of diagnosing multiple sclerosis
Symptoms of multiple sclerosis can be uncomfortable and advance quickly for some. This makes it extremely important to diagnose the disease in a timely manner, especially since there are other even more serious conditions that could have similar symptoms. Not only can therapy and treatment begin sooner; it can also help relieve a patient from the burden of waiting to learn the truth.
More concerning in the need for early diagnosis are some of the latest discoveries involving MS.
- Unlike previous theories have suggested, it’s been proven that, even in the earliest stages of the disease, the attack on the nervous system can lead to permanent neurological damage for the patient.
- Just a few months ago, the latest findings doubled the estimation of how many people are likely suffering from MS, whether diagnosed or not. Previous projections were approximately 400,000 in the United States but are now believed to be over one million.
With the number of people, as well as the risks, increasing for the early stages, it’s more important than ever to diagnose the problem. But how can that be done?
Definitive criteria for a multiple sclerosis diagnosis
The testing and verification process required to diagnose multiple sclerosis can be rigorous. That’s because a doctor has to meet certain guidelines before he can label a disease or ailment on the roster of symptoms presented, especially when it comes to multiple sclerosis. In order to determine a positive diagnosis of any type of MS, a doctor must find that:
- The patient’s central nervous system or CNS, which is made up of the brain, the spinal cord, and the optic nerves, show clear evidence of damage in at least two different places within the system;
- Find that there have been at least two occurrences of symptoms and/or attacks, if not more, that have led to this damage (a single occurrence causing damage to the CNS is not classified as multiple sclerosis but rather clinically isolated syndrome, which is literally a single episode of the occurrence of symptoms related to MS); and
- Find that there are no other possible causes of the same set of symptoms by ruling out know diseases, conditions, and ailments that also present as a similar set of symptoms.
Typically, all of this is carried out by a neurologist, who specializes in medical knowledge of the CNS. It’s very deep and involved, and the process can be grueling. However, there is a battery of tests that can be run to meet these criteria in order to come up with a clear diagnosis. One of the newest potential tests, which is completely noninvasive (a relief compared to several other testing options) is the Evoked Potential Test, or EP test.
What is an evoked potential test?
Sensory information is taken in as electrical signals that are processed through the central nervous system, or CNS. These impulses translate in the brain and are sent back through the network of nerves as touch, taste, sound, sight, or smell. The optic nerves are a vital part of the CNS, and an evoked potential test uses these nerves to help find particular symptoms that could prove or disprove a diagnosis of multiple sclerosis (a VEP – visual evoked potential – test).
Here, the electrical activity that takes place with light stimuli is recorded, detecting variations that show slowing of the signals or damage to the nerve “blueprint” on the retina. This test is performed with the patient sitting in front of a screen and watching something like a checkerboard pattern that alternates.
There are other types of EP tests, including:
- BAEP – Brain auditory evoked potential requires a patient to listen to a series of clicks that come through each ear.
- SEP – Sensory evoked potential tests send short electrical pulses through a single arm or leg to trace the timing and effect on the nerves.
- MEP – Motor evoked potential testing isn’t normally utilized in the diagnosis of MS but is available to discover any damage to the nervous system that could affect your ability to move.
The best thing about an EP test is that it is noninvasive and painless. It does take time, since many neurologists will want to perform the three common types of EP tests all at once. That means about two hours with wires attached to the scalp to get a clear picture of what’s going on in the brain.
Unfortunately, a diagnosis of multiple sclerosis can’t be made through EP tests alone. These tests can’t determine if other ailments or underlying diseases could be the cause of the damage to the nervous system.
Other testings for multiple sclerosis
To be thorough, especially in the elimination process, doctors trying to diagnose or reject the possibility of MS in a patient start with a discussion, looking for information such as:
- Has the patient had any history of these symptoms in the past that could have been caused by MS that could be recurring?
- What is in the family and medical history for the patient? Where were they born, and what environmental factors were they exposed to? Are there any potential factors such as other illnesses involved? Where has the patient traveled?
- Is the patient suffering from any loss of mental, emotional, or speech function? How are their balance, coordination, reflex, strength, vision, motor skills, and other sensory capabilities?
After the extensive discussion, a panel of tests will likely be ordered to help qualify the symptoms presented as multiple sclerosis, alongside the EP test.
- MRI – Magnetic Resonance Imaging will show potential swelling and damage to nerves in the brain and spinal cord in a noninvasive way.
- Cerebrospinal Fluid – The doctor will perform a spinal tap, taking a sample of the fluid to look for particular markers of MS within the fluid.
- OCT – An optical coherence tomography shows damage to the retinal structure and optic nerves, including optic neuritis, which is common in patients with MS.
Types of Multiple Sclerosis
Once it’s determined that a patient has multiple sclerosis, the doctor must identify the type or stage of the disease.
- RRMS – Relapsing-remitting multiple sclerosis has symptoms occurring for a short time (at least 24 hours), then going into “remission” for at least thirty days and often months or years before returning or “relapsing” with no progression of severity.
- SPMS – Secondary progressive MS typically follows after RRMS, with the patient no longer having any remission and, therefore, no relapses. Constant symptoms never disappear and tend to worsen over time.
- PRMS – Progressive relapsing multiple sclerosis is the rarest type of MS and relapses and remits but with the progression or advancement of severity seen in SPMS.
- PPMS – Primary progressive MS doesn’t affect many. It’s diagnosed to older people and is the same as SPMS, but without the prior RRMS remissions and relapses.