Evaluation of median nerve by shear wave elastography and diffusion tensor imaging in carpal tunnel syndrome

Eur J Radiol. 2018 Apr;101:59-64. doi: 10.1016/j.ejrad.2018.02.005. Epub 2018 Feb 9.

Abstract

Purpose: The aim of the current study is to investigate the diagnostic role of shear-wave elastography and diffusion tensor imaging in patients with carpal tunnel syndrome.

Material and methods: The study included a total of 77 wrists; 18 normal, 35 wrists with mild, 9 wrists with moderate and 15 wrists with severe carpal tunnel syndrome. Elastography of the median nerve was performed by defining the boundaries of a segment of the nerve at sagittal plane at the level of proximal carpal row. Additionally, the cross-sectional area of the median nerve was evaluated. Fractional anisotropy and apparent diffusion coefficient measurements were carried out by placing region-of-interest at three levels: at pisiform bone (carpal tunnel inlet), mid carpal tunnel, and hook of hamate (carpal tunnel outlet).

Results: Patients with carpal tunnel syndrome had higher elasticity values of median nerve (53.0 kPa; IQR 40.8-77.0 kPa) compared to control subjects. (36.8 kPa; IQR 31.0-39.9 kPa) Patients with moderate-severe carpal tunnel syndrome had higher elasticity values (82 kPa; IQR 64.0-95.5 kPa) compared to patients with mild carpal tunnel syndrome. (44 kPa; IQR 32.5-59.5 kPa) Patients with carpal tunnel syndrome had lower fractional anisotropy at mid-carpal level (0.382; IQR 0.330-0.495) compared to the control group. (0.494; IQR 0.434-0.537) Patients with moderate-severe carpal tunnel syndrome had lower fractional anisotropy values (0.366; IQR 0.331-0.407) and higher apparent diffusion coefficient values (1.509 mm2/s; IQR 1.374-1.733 mm2/s) compared to patients with mild carpal tunnel syndrome. (0,423; IQR 0.324-0.526 and 1.293 mm2/s; IQR 0.967-1.514 mm2/s) CONCLUSION: Shear-wave elastography and diffusion tensor imaging are helpful imaging modalities in diagnosing carpal tunnel syndrome and assessing its severity.

Keywords: Carpal tunnel syndrome; Diffusion tensor imaging; Median nerve; Shear-wave elastography.

Publication types

  • Evaluation Study

MeSH terms

  • Adult
  • Aged
  • Anisotropy
  • Carpal Bones / diagnostic imaging
  • Carpal Tunnel Syndrome / diagnostic imaging*
  • Case-Control Studies
  • Diffusion Tensor Imaging / methods
  • Elasticity Imaging Techniques / methods*
  • Female
  • Humans
  • Male
  • Median Nerve / diagnostic imaging*
  • Median Nerve / physiology
  • Middle Aged
  • Prospective Studies
  • Wrist / diagnostic imaging
  • Wrist Joint / diagnostic imaging