SEARCH RESULTS FOR: Multiple-Sclerosis-on-Brain-MRI

Multiple-Sclerosis-on-Brain-MRI

Classic Findings of Multiple Sclerosis (MS) on Brain MRI Authors: Evan Allarie Davis Maclean Viesha Ciura* Reviewers: Yan Yu* * MD at time of publication infiltrates in the infratentorial region Note: variation in findings exist. The findings shown here are not exhaustive but are some of the most common areas implicated on brain MRI in MS. Most common sites that lesions are observed are: juxtacortical regions, periventricular, infratentorial, spinal cord, and the optic nerve. However lesions can occur anywhere there is myelin in the CNS. Active inflammation and destruction allows for gadolinium contrast to cross the blood- brain barrier, which can be visualized as a marker of active inflammation in MS Classic optic nerve (CN II) lesion seen in optic neuritis. Gadolinium enhancement (↑ signal intensity of lesion after gadolinium injection) in this T1 image demonstrates active inflammation Image Credits: Dr. Viesha Ciura For further pathogenesis, see the Calgary Guide slide: Multiple Sclerosis (MS): Pathogenesis and Clinical Findings Inflammation within the central nervous system (CNS) T-cell, B-cell, and macrophages infiltrate CNS Infiltration occurs through veinsàlocal inflammation Perivenular infiltrates around the medullary veins (perpendicular to ventricles) Inflammation and blood-brain barrier destruction ↑ extravascular inflammatory fluid around lesions, which appears hyperintense/bright Loss of neuronal/axonal density in affected region, replaced by gliosis over time Lesions extend out around veins, creating characteristic ovoid lesions Classic hyperintense T2/FLAIR perpendicular periventricular plaques following the medullary veins – ‘Dawson’s Fingers’ Middle cerebellar peduncle T2/FLAIR hyperintense lesion in classic location for MS Legend: Pathophysiology Mechanism Sign/Symptom/Lab Finding Complications Published October 25, 2020 on www.thecalgaryguide.com