Abnormal findings on an initial brain MRI occur in approximately 65 to 80 percent of patients with a first attack of optic neuritis, and follow-up of patients with an abnormal MRI showed that 80 to 90 percent of these people developed definite multiple sclerosis. This data is what compelled your neurologist to say that you have a high likelihood of MS. In addition, there is a rough correlation between the number of lesions on the initial MRI and the time until the next attack of symptoms. In one study, patients with three or more lesions had a shorter time to the next relapse compared with patients with one or two lesions. An “average” number of lesions on the initial brain MRI is between 10 and 15. However, even a few lesions are considered significant because even this small number of spots allows us to predict a diagnosis of MS and start treatment. Q2. I recently became very ill and was hospitalized. They did an MRI and discovered a lesion in my right side of my brain. They did a biopsy, lumbar puncture, visual evoked response test and a ton of blood work. After 12 days of being hospitalized, I was told they can’t say for sure that I have MS because I only have one lesion. Can I have MS with just one lesion? I am so confused. The diagnosis of multiple sclerosis cannot be specifically made with one lesion. However, there certainly can be a very high suspicion of multiple sclerosis. What you described unfortunately is not an uncommon scenario. Many times, the diagnosis of multiple sclerosis can be very difficult and even though there may be a high suspicion based on the situation; a specific diagnosis cannot be made in spite of biopsies, lumbar punctures, MRIs, evoked potentials and blood work. The diagnosis of multiple sclerosis remains a “clinical diagnosis” meaning that all the pieces of the puzzle do have to fit together to form the picture that is consistent with multiple sclerosis. There have been a number of clinical trials with all the various treatments for multiple sclerosis in patients potentially like yourself that have what is called a “clinically isolated syndrome” which specifically means that there has only been one episode rather than “multiple episodes.” However, the MRIs or other studies including spinal fluid examination may be consistent with multiple sclerosis. Although it is very frustrating and difficult before the diagnosis is made, it may take time. It is important to be sure that there is not some other explanation for what you described other than multiple sclerosis that could be occurring. Although it is frustrating and confusing, it sounds as though your physicians are trying to be very appropriate and trying to be certain of the diagnosis before committing you to a diagnosis of multiple sclerosis, and this may just take time. Q3. How many new lesions before you say your drug is not working? I had five lesions when I was diagnosed five years ago. Then after another MRI I now have 22 lesions. I have been on the same drug for five years. Would you say this is normal progression? Or is it not acceptable and time to try another drug? Do we decide a drug is not working by the number of new lesions or by symptoms or is it the combination of both? There is not necessarily a “normal” progression of multiple sclerosis. We do know that MS is a chronic progressive disease that will likely worsen over time. However, studies have shown that current treatments do work and hopefully would significantly impact the number of either acute or chronic lesions seen on MRI. If there were five lesions five years ago and there are now 22 lesions — even if there are no clinical symptoms — this would cause concern that the present therapy is not as effective as hoped. The question is whether these lesions are new acute, inflammatory lesions — that is, they are seen after intravenous contrast with gadolinium — or are they new white matter plaques that suggest more chronic changes. In either case, with that number of new lesions, considering a change of therapy would be appropriate. It should be noted that the number of lesions do not directly correspond to the level of disability. It really depends on where in the brain these lesions occur. We call this the “volume of disease.” Although there may not be obvious physical changes (such as weakness, paralysis, numbness or tingling, etc.) with increasing volume of disease, studies do suggest that cognitive changes do appear to be more directly related to the volume of white matter lesions on the brain. Thus, further discussion with your neurologist regarding other therapies may be appropriate. Learn more in the Everyday Health Multiple Sclerosis Center.
