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Updated: Feb 7, 2026

CMAP Scan MUNE MScan - A Novel Motor Unit Number Estimation MUNE Method
Published on: June 7, 2018
Following disease progression in motor neuron disorders with 3 motor unit number estimation methods
Anna Bystrup Jacobsen1, Hugh Bostock2, Hatice Tankisi1
1Department of Clinical Neurophysiology, Aarhus University Hospital, Nørrebrogade 44, 8000, Aarhus C, Denmark.
Introduction:
The objective of this study was to evaluate a recently developed motor unit number estimation (MUNE) method, MScanFit MUNE (MScan), as a measure of disease progression in amyotrophic lateral sclerosis (ALS) compared with compound muscle action potential (CMAP) amplitude and 2 traditional MUNE methods.
Methods:
ALS patients were evaluated clinically using the ALS Functional Rating Scale-Revised (ALSFRS-R). MScan, multiple-point stimulation MUNE (MPS), and motor unit number index (MUNIX) were performed in the abductor pollicis brevis (APB) muscle at baseline (27 patients), 4 months (23 patients), and 8 months (16 patients).
Results:
Of the 5 measures, MScan registered the largest decline (8.7% per month), compared with MPS (3.4%), MUNIX (4.8%), CMAP amplitude (2.0%), and ALSFRS-R (1.9%). Only MScan and ALSFRS-R registered significant decrements over 4 and 8 months.
Discussion:
MScan may be useful as a sensitive, objective tool for quantifying motor unit loss in ALS. Muscle Nerve 59:82-87, 2019.
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