Sonography of the median nerve in CMT1A, CMT2A, CMTX, and HNPP

Muscle Nerve. 2013 Mar;47(3):385-95. doi: 10.1002/mus.23681. Epub 2013 Feb 4.

Abstract

Introduction: In this study we compare the ultrasound features in the median nerve in patients with different types of Charcot-Marie-Tooth (CMT) disease and hereditary neuropathies with liability to pressure palsies (HNPP) as a typical entrapment neuropathy.

Methods: Median nerve ultrasound and conduction studies were performed in patients with CMT1A (n = 12), MFN2-associated CMT2A (n = 7), CMTX (n = 5), and HNPP (n = 5), and in controls (n = 28).

Results: Median nerve cross-sectional area (CSA) was significantly increased in CMT1A, whereas, in axonal CMT2A, fascicle diameter (FD) was enlarged. CSA correlated with nerve conduction slowing in CMT1A and with axonal loss, as shown by motor and sensory nerve amplitudes in both CMT1A and CMT2A. A relatively low wrist-to-forearm-ratio (WFR <0.8) or a relatively high WFR (>1.8) appeared to be unlikely in MFN2 and Cx32 mutations of CMT2A and CMTX, respectively.

Conclusion: Differences in CSA, FD, and WFR of the median nerve can be helpful in defining subtypes of hereditary neuropathies.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adolescent
  • Adult
  • Aged
  • Charcot-Marie-Tooth Disease / diagnostic imaging*
  • Charcot-Marie-Tooth Disease / genetics
  • Connexins / genetics
  • Electrodiagnosis
  • Electrophysiological Phenomena
  • Female
  • Forearm / anatomy & histology
  • Forearm / innervation
  • GTP Phosphohydrolases / genetics
  • Hereditary Sensory and Motor Neuropathy / diagnostic imaging*
  • Hereditary Sensory and Motor Neuropathy / genetics
  • Humans
  • International Classification of Diseases
  • Male
  • Median Nerve / diagnostic imaging*
  • Middle Aged
  • Mitochondrial Proteins / genetics
  • Myelin Proteins / genetics
  • Neural Conduction / physiology
  • Phenotype
  • Ultrasonography
  • Wrist / anatomy & histology
  • Wrist / innervation
  • Young Adult

Substances

  • Connexins
  • Mitochondrial Proteins
  • Myelin Proteins
  • PMP22 protein, human
  • connexin 32
  • GTP Phosphohydrolases
  • MFN2 protein, human

Supplementary concepts

  • Charcot-Marie-Tooth Disease, Axonal, Type 2a1
  • Charcot-Marie-Tooth disease, X-linked, 1