neurologic disorders
Multiple Sclerosis (MS)
Diagnosis of Multiple Sclerosis
Clinical criteria Brain and spinal MRI Sometimes cerebrospinal fluid (CSF) IgG levels and evoked potentials Multiple sclerosis is suspected in patients with Optic Neuritis , MRIis the most sensitive imaging test for MS and can exclude other treatable disorders that may mimic MS, such as nondemyelinating lesions at the junction of the spinal cord and medulla (eg, subarachnoid cyst, foramen magnum tumors). Gadolinium-contrast enhancement can distinguish actively inflamed from older plaques. Also, higher-field MRI magnets (3 to 7 Tesla) can distinguish perivenular MS plaques from nonspecific white-matter lesions. MS must be distinguished from the following: Clinically isolated syndromes (consisting of only a single clinical manifestation typical of MS) Radiologically isolated syndrome (MRI findings typical of MS that are incidentally noted in patients with no clinical manifestations) MS can be distinguished because diagnosis of MS requires evidence of CNS lesions that are separated in both time and space (location in the CNS). For example, any of the following can indicate separation in time: A history of exacerbations and remissions MRI that shows simultaneous enhancing and nonenhancing lesions, even if patients are asymptomatic A new lesion on a subsequent MRI in patients with a previous lesion Separation (dissemination) in space can be established by finding lesions in ≥ 2 of the 5 following CNS areas typically affected by MS ( Diagnosis reference ): Periventricular: ≥ 3 lesions Cortical/juxtacortical (white matter next to cortex and/or cortex): ≥ 1 lesions Infratentorial: ≥ 1 lesions Spinal cord: ≥ 1 lesions Optic nerve: ≥ 1 lesions (either by MRI or clinical evaluation) If MRI plus clinical findings are not diagnostic, additional testing may be necessary to objectively demonstrate separate neurologic abnormalities. Such testing may include evoked potentials and, occasionally, CSF examination or blood tests. Measurement of Evoked Responses None is being done less frequently (because the diagnosis can usually be based on MRI) but can be helpful if MRI plus clinical findings are inconclusive or if infection (eg, CNS Lyme Disease ) must be ruled out. CSF tests include opening pressure, cell count and differential, protein, glucose, IgG, oligoclonal bands, and usually myelin basic protein and may be necessary. Sometimes systemic disorders (eg, Systemic Lupus Erythematosus (SLE) ) and infections (eg, 1.Filippi M, Rocca MA, Ciccarelli O, et al: MRI criteria for the diagnosis of multiple sclerosis: MAGNIMS consensus guidelines.Lancet Neurol15 (3):292–303, 2016. doi: 10.1016/S1474-4422(15)00393-2 