Diagnosing MS Isn't Easy — Here's Why
This article is for undiagnosed people that go to online MS forums, list their symptoms, and ask if they have MS. It’s also for those who track their symptoms, Google them, and convince themselves they have MS. Folks, it’s just not that simple. Here’s why.
How neurologists test for MS
Neurologists make the diagnosis partly based on a neurological exam that checks all your cranial nerves, reflexes, coordination, balance, and vision.1 Some of the tests may involve a tuning fork to check sensation; standing with our eyes closed to see if we sway, fall down, maintain our upright stance, or surprise them with something completely different. Our knees and elbows may get hammered for reflex briskness or an absence of rebound. And there are many more weird little procedures that can expose a unilateral abnormality (just on one side), as well as limited vision, hearing, and touch. As thorough as it is, it’s just a snapshot in time.
MS is similar to other conditions
But MS poses some small problems. First, it tends to show itself in bits and pieces over time. Second, the symptoms—of which there are many—can indicate a bushel of other medical conditions. For example, one foot might have developed numbness. Maybe it started in one toe and then spread to the entire foot. Maybe it's an early sign of MS. But it can also signal diabetes, or something associated with damage to peripheral nerves (those located in the extremities and outside the central nervous system).2,3
The need for blood work
This is why MS diagnostic tests involve blood work. While there is no blood test available to diagnose MS, as of this writing, blood tests can still help rule it out by identifying other causes, such as Lyme disease or diabetes.4,5
If blood work tests negative, the diagnostician can turn to brain and spine MRIs. Lesions consistent with MS can appear in certain areas of the brain and cervical spine, and with a certain appearance and shape that a trained eye may determine is being caused by MS and perhaps not a migraine, aging, or cancer.6 Radiologists and neurologists are not all equally gifted in this area, however. Doubt can linger, delaying a diagnosis and treatment. A misdiagnosis can delay proper treatment.
Other diagnostic tests
Evoked potentials testing involves sticking electrodes to your scalp. For vision, you may stare at a checkerboard while a machine measures how long it takes electrical signals to travel from your eyes to your brain. For hearing, tones may be sounded while the machine measures the speed at which signals travel from ear to brain. It’s just one more piece to add to the puzzle.7
A lumbar puncture, or spinal tap, checks the cerebrospinal fluid for signs of inflammation within the closed system of the brain/spinal cord. If such inflammation exists, bands can appear.8
The tests could still be inconclusive
Now you’ve completed much of the diagnostic testing for MS. After all that grief, the diagnosis should float to the surface as easily as in a Magic 8-Ball, right? Not necessarily.
If you have MS, you still might not have tested positive in all the MS tests.9 Let’s say the blood tested negative for all differential diagnoses. But a person also had negative lumbar puncture; one iffy spot in the brain MRI and none in the spine; iffy evoked potentials; and mostly normal physical exam with some iffy things such as numbness and one brisk reflex. Result? No diagnosis at this time. Not for MS and not for anything else.
Watching and waiting after the first signs
Now, you wait. You keep track of your symptoms. Whenever there is a change, you can see your doctor.
This is the course many people with MS follow on their way to a diagnosis. Some people never get diagnosed. Others eventually get misdiagnosed or properly diagnosed with another disease. In any case, diagnosing MS is not a piece of cake and likely won’t be for some time to come.
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