How terrible that your neurologist can not make his / her mind up.
They state 'non specific white matter lesions', OK then the episode that you had that landed you in the ER was specific. People don't have that happen and not a reason behind it. It is totally neurological. The length of time that you described one being 3 days and the other approx 1 week. Let me ask you this: It stopped all on it's own, didn't it? No reason for it to start, terrorized and entertained you for a bit and then left. If it is MS, that is called a flare, attack.
I've done a little research on the Periventricular Lesion as well as additional info on MS and this is what I have for you:
Causes of periventricular white matter lesions:
Casues of periventricular white matter (PWM) lesions include normal senescent changes (then they are called UBO's, for "unidentified bright objects), small strokes, and disorders related to multiple sclerosis (MS). PWM are correlated with vitamen B6 (pyridoxine) deficiency.
Getting older: Age is certainly the single most common cause of PWM. This is presumably a "wear and tear" phenomenon.
Small strokes: A period of hypertension is a common cause. In the authors experience, just a few days of extreme hypertension may be enough. This might suggest that small bleeds are the cause in some. Clinical studies also show association with diabetes, but not consistently with atherosclerosis. PWM are often an accompaniment of migraine, and occur in roughly 20% of persons with migraine. As about 10% of the population has migraine, this means that about 2% of the population has white matter lesions due to migraine.
MS and related conditions: Demyelinating disorders such as multiple sclerosis and relatives can cause PWM. There is an incredibly rare and a familial variant, called CADASIL. Testing for the notch-3 mutation that causes CADASIL is done by laboratories.
MS Testing:
Additional tests: evoked potential, CSF, and blood
It is not usually necessary to do all diagnostic tests for every patient. If, however, a clear-cut diagnosis cannot be made based on the tests above, additional tests of evoked nerve potentials, cerebrospinal fluid (CSF), and blood may be ordered.
Evoked potential tests are electrical diagnostic studies that can show if there is a slowing of messages in the various parts of the brain. They often provide evidence of scarring along nerve pathways that is not apparent on a neurologic exam.
Cerebrospinal fluid (CSF), usually taken by a spinal tap, is tested for levels of certain immune system proteins and for the presence of oligoclonal bands. These bands indicate an abnormal autoimmune response within the central nervous system, meaning the body is producing an immune response against itself. Oligoclonal bands are found in the spinal fluid of a percentage of people with MS, but since they are present in other diseases as well, they cannot be relied on as positive proof of MS. They may also take some years to develop.
Blood tests: There is no definitive blood test for multiple sclerosis; however, blood tests can rule out other causes for various neurologic symptoms. Some other conditions that cause symptoms similar to those of MS are Lyme disease, a group of diseases known as collagen-vascular diseases, certain rare hereditary disorders.
When my neuro first gave me the dx of MS I was somewhat relieived as that is what I figured and then he wanted a LP, I agreed, no bands so he retracted the dx so I empowered myself with as much info that I could regarding MS and different resources and I educated myself and him along the way. I truly believe it boils down to what they are taught and their personal belief of what MS is and how it acts in different people.
Also some docs really hate giving a dx of MS to anyone especially someone as young as you. Looking back I've had MS since my early 20's...symptoms would come and go and didn't last long enough or painful to warrent a trip to the doctor so I would shug it off as working too hard, pulled a muscle, slept on hand funny, etc.... Now looking back, it was probably MS playing with me all that time. I was finally dx at the age of 36 and that was 8 years ago. Actually come to think of it when I moved back to my home state I visited my PCP for several years of annoying things and he always had an answer but it made no sense to me as to how that happened but then again I'm not a doc. Approx 7 / 7 1/2 years ago I got a copy of my medical records and he put in there 'doubtful she has MS' and this was after my neurologist sent notification to him that I indeed had MS. Needless to say I switched premantently back to another doctor in his practice.
Ask your neurologist this: Is it not important to find out what happened to me that landed me in the ER?
Until a definate dx can be given, most neurologist will put a person on an MS drug as it is the only thing that can slow down the progression when there is a question of probable MS.
~Zig