Magnetic Resonance Imaging (MRI)
The MRI scanner takes detailed pictures of the Brain and Spinal Cord, showing areas of Sclerosis (Lesion, Plaque), when they are larger than 2mm (Macroscopic Lesions).
Scans can NOT show Microscopic Lesions, as they are too small for current imaging resolutions; but are included in your Lesion Load and Atrophy totals. These early smaller lesions are better documented, by EVP testing, which are equally valid in meeting a Laboratory Supported Definite Multiple Sclerosis diagnosis.
While this is the only test in which some Multiple Sclerosis Lesions can be seen, it cannot be regarded as conclusive; because, all lesions do not register on MRI scans and many other diseases can produce identical MRI images.
MRI shows the size, quantity and distribution of Lesions larger than 2mm, and together with supporting evidence from your other diagnostic tests, Medical History, and Neurologic Examination, may be a positive finding that confirms the MS diagnosis.
It also provides an objective measure (Para-Clinical Evidence) of MS lesion activity in the Brain and Spinal Cord.
However, Conventional MRI (T1 and T2 images) are NonSpecific (cause unknown), have little relation to MS progression, and insufficiently correlation with disability.
Magnetization Transfer and Proton MR Spectroscopy are two imaging techniques that better correlate with MS activity. They are not yet widely used, but newer more specific imaging protocols are presently being formulated.
Abnormal MRI scans are found in
- 96% with a definite diagnosis of MS
- 70% with a diagnosis of probable MS
- 30%-50% with possible MS
MRI Criteria for diagnosing MS
- At least 3 Lesions and two of the following:
- Lesions abutting the Lateral Ventricles
- Lesions with diameters greater than 5mm
- Lesions present in the Posterior Fossa (InfraTentorial)
Lumbar Puncture (Spinal Tap)
In this test, CerebroSpinal Fluid (the fluid which flows around the Brain and Spinal Cord) is tested for the presence of OligoClonal Bands (AntiBodies), and fragments of Myelin Basic Protein.
Intrathecal production of Ig G can occur with MS, but is also found with other Neurologic conditions. A positive finding is most common in Progressive MS, while it is usually negative in Relapsing MS, unless you are having or recently had an Exacerbation.
The CSF is taken from the Spinal Cord by inserting a needle into the Spinal Canal and withdrawing a small amount of fluid. A local anesthetic is given to numb the skin and while it is uncomfortable, it is not too painful.
A Spinal Tap, does require you to lay flat for a number of hours after the test (many experience very painful headaches when standing or sitting). You may require an overnight stay in a hospital, subsequently, a short period of recuperation may be required. This test may indicate MS but is NOT in itself conclusive.
The diagnosis of MS is not always clear cut. The initial symptoms may be transitory, vague and confusing to both you and the doctor.
Invisible and/or subjective symptoms are often difficult to communicate to doctors, who often do not believe what they cannot see (If I don't see it, you do not have it.) and too often dismiss people as being neurotic.
Your doctor may not have even told you that MS was suspected; because, he or she may want to see at least two distinct episodes with symptoms that are separated, by at least one month and lasting for at least 24 hours (Poser Criteria). This medical criteria must be met before a confirmed diagnosis, of Multiple Sclerosis can be reached.
A good relationship with your Neurologist and family physician is essential. If you do not have a good relationship, by all means, take the time to locate one (Good Doc's List) you do have confidence in. MS may have times of crisis and require specialized medical knowledge, but it is a disease that must be lived and managed every day.
This goal can only be accomplished, if you and your physican trust and have confidence in each other. The time of diagnosis is stressful, not only for MSers, but also for your whole family, friends, and carers.
They should also be fully informed of your diagnosis, prognosis, treatment management plan, and the lifestyle adjustments - necessitated by MS. Receiving the diagnosis of MS can be a shock, your physician and local MS Society are vital resources, for you and your family.
Allow for the demands Multiple Sclerosis requires; in time, you can sucessfully manage your MS and achieve a fullfilling life. This may surprise you; but, MSers can and do have productive, very complete lives.
Multiple Sclerosis - Radiology Assistant - MRI
by: Frederik Barkhof and Robin Smithuis
Inflammation, DeMyelination, NeuroDegeneration and NeuroProtection in the Pathogenesis of Multiple Sclerosis
by: Lisa K. Peterson, BS and Robert S. Fujinami, PhD
Diagnosing Multiple Sclerosis
by: National Multiple Sclerosis Society