European Radiology

, Volume 21, Issue 8, pp 1764–1771

Brachial plexus MR imaging: accuracy and reproducibility of DTI-derived measurements and fibre tractography at 3.0-T

  • Alberto Tagliafico
  • Massimo Calabrese
  • Matteo Puntoni
  • Daniele Pace
  • Gabriella Baio
  • Carlo Emanuele Neumaier
  • Carlo Martinoli
Musculoskeletal

DOI: 10.1007/s00330-011-2100-z

Cite this article as:
Tagliafico, A., Calabrese, M., Puntoni, M. et al. Eur Radiol (2011) 21: 1764. doi:10.1007/s00330-011-2100-z

Abstract

Objective

To estimate intrastudy, intraobserver and interobserver reproducibility of DTI-derived measurements and fibre tractography (FT) at 3.0 T MR imaging in subjects without known brachial plexus pathology.

Methods

IRB approval and written informed consent were obtained. Forty healthy volunteers underwent bilateral 3.0-T DTI of the brachial plexus. Postprocessing included FT and analysis of fractional anisotropy (FA) and apparent diffusion coefficient (ADC). Four authors performed postprocessing and analysis independently and in different sessions at baseline and after 4 weeks. Non-parametric tests and Bland-Altman statistics were used.

Results

Minimum and maximum percent variability were 6% and 20% for FA (85%–93% reproducibility). For ADC minimum and maximum percent variability were 6% and 18% (86%–97% reproducibility). Quality of fibre tract was rated equal in 80% and slightly different in 20% of subjects. Minimum detectable differences between limb were 37% for FA and 32% for ADC. Intra- and inter-observer agreement were good. Evaluating the combined influence of the observer and of the repeated measurements the reproducibility was 81–92%.

Conclusion

DTI of brachial plexus nerves is reliable. The healthy contralateral side can be used as an internal control considering that changes in FA and ADC values of less that 37% and 32% will not be clinically detectable with confidence.

Keywords

Diffusion tensor imagingBrachial plexusReproducibilityFractional anisotropyApparent diffusion coefficientMRIMinimum detectable differencesRepeatibility

Abbreviations

DWI

Diffusion-weighted imaging

DTI

Diffusion Tensor Imaging

MR

Magnetic Resonance

FA

Fractional Anisotropy

ADC

Apparent Diffusion Coefficient

ROI

Region of Interest

DTI-FT

Fibre Tracking (with Diffusion Tensor Imaging)

FOV

Field of View

SAR

Specific Absorption Rate

Copyright information

© European Society of Radiology 2011

Authors and Affiliations

  • Alberto Tagliafico
    • 1
  • Massimo Calabrese
    • 1
  • Matteo Puntoni
    • 2
  • Daniele Pace
    • 1
  • Gabriella Baio
    • 1
  • Carlo Emanuele Neumaier
    • 1
  • Carlo Martinoli
    • 3
  1. 1.Department of RadiologyNational Institute for Cancer Research (IST)GenovaItaly
  2. 2.Clinical Trials Research UnitGalliera HospitalGenovaItaly
  3. 3.Department of Radiology- DISCUniversity of GenovaGenovaItaly