1. Amyotrophic Lateral Sclerosis (ALS) versus Multifocal Motor Neuropathy (MMN) : Utility of MR Neurography
ALS and multifocal motor neuropathy exhibit distinct phenotypes on MR neurography.
ALS showed normal or moderately hyperintense nerves without fascicular enlargements (reader 1, 22 of 22 [100%] participants; reader 2, 21 of 22 [95%] participants) together with prominent muscle denervation edema and possible muscle atrophy.
MMN exhibited prominent fascicular enlargements of peripheral nerves (reader 1, six of eight [75%] participants; reader 2, seven of eight [88%] participants) without any or with only marginal muscle denervation edema and usually absence of muscle atrophy.
Example MR neurography T2 images (ALS and MMN) of lumbosacral plexus show both femoral, L5, and S1 nerves. Fascicular enlargements dominate in MMN.
Kronlage M et al. Published Online: May 7, 2019