Intra- and internerve cross-sectional area variability: new ultrasound measures

Muscle Nerve. 2012 May;45(5):730-3. doi: 10.1002/mus.23252.


Introduction: Nerve involvement in immune-related neuropathies is non-homogeneous, and therefore characterization of ultrasound (US) abnormalities is difficult. We developed two measures to quantify US abnormalities in immune-related neuropathies.

Methods: Intranerve cross-sectional area (CSA) variability for each nerve was calculated as: maximal CSA/minimal CSA. Internerve CSA variability for each patient was calculated as: maximal intranerve CSA variability/minimal intranerve CSA variability. Six patients underwent US evaluation of the median, ulnar, and fibular nerves, and the abnormalities were scored with our newly developed measures.

Results: The new measures were applicable to all nerves and patients. The highest degree of intra- and internerve CSA variability was observed in multifocal motor neuropathy, consistent with the asymmetric characteristics of this neuropathy.

Conclusions: The application of intra- and internerve CSA variability measures allows us to quantify the heterogeneity of nerves and nerve segments and identify different US patterns in diverse immune-related neuropathies.

MeSH terms

  • Adolescent
  • Adult
  • Aged
  • Aged, 80 and over
  • Female
  • Humans
  • Male
  • Median Nerve
  • Middle Aged
  • Peripheral Nerves / diagnostic imaging*
  • Peroneal Nerve
  • Polyneuropathies / diagnostic imaging*
  • Polyneuropathies / pathology*
  • Ulnar Nerve
  • Ultrasonography, Doppler / methods*