Related Experiment Video
Updated: Nov 29, 2025

CMAP Scan MUNE MScan - A Novel Motor Unit Number Estimation MUNE Method
Published on: June 7, 2018
Use of CMAP, MScan fit-MUNE, and MUNIX in understanding neurodegeneration pattern of ALS and detection of early motor
Taskin Gunes1, Nermin Gorkem Sirin2, Sevki Sahin3
1Department of Neurology, Marmara University Hospital, Istanbul, Turkey; VM Maltepe Medicalpark Hospital, Istanbul, Turkey.
Background:
The pattern of lower motor neuron (LMN) degeneration in amyotrophic lateral sclerosis (ALS), i.e., dying-back (from the nerve ending to cell body) or dying-forward (from the cell body to nerve ending), has been widely discussed. In this study, we aimed to evaluate LMN loss using compound muscle action potential (CMAP), motor unit number index (MUNIX), and MScan-fit-based motor unit number estimation (MUNE) to understand the pattern of neurodegeneration in ALS.
Methods:
Twenty-five patients were compared with 25 controls using CMAP amplitude and area, MUNIX, and MScan-fit MUNE in three proximal and distal muscles innervated by the ulnar nerve.
Results:
Unlike the controls, the CMAP area, MScan-fit MUNE, and MUNIX recorded in ALS patients showed more neurodegeneration in distal muscles than proximal muscles. In ALS patients with unaffected CMAP amplitudes (n = 13), the CMAP area, MScan-fit MUNE, and MUNIX showed subtle motor unit loss of 30.7 %, 53.8 %, and 38.4 %, respectively.
Conclusion:
The CMAP area, MScan-fit MUNE, and MUNIX showed neurodegeneration earlier than the reduction in CMAP amplitude. These tests confirmed dying-back neurodegeneration, while only MUSIX showed re-innervation in ALS.
More Related Videos
06:35In Vivo Electrophysiological Measurement of Compound Muscle Action Potential from the Forelimbs in Mouse Models of Motor Neuron Degeneration
Published on: June 15, 2018
09:07Electrophysiological Motor Unit Number Estimation MUNE Measuring Compound Muscle Action Potential CMAP in Mouse Hindlimb Muscles
Published on: September 25, 2015