MR microneurography of human peripheral fascicles using a clinical 3T MR scanner

Abstract

Background and purpose: Knowledge of nerve fascicular structures is essential for managing peripheral nerve disorders. This study aimed to investigate the feasibility of z-axis high-resolution magnetic resonance (MR) microneurography (zH-MRMN) in displaying the three-dimensional structures of tibial nerve fascicles in vivo using a 3T MR scanner.

Materials and methods: Twelve volunteers underwent z-axis conventional-resolution MR microneurography (zC-MRMN) and zH-MRMN of tibial nerves. The visibility scores of the nerve fascicles (VSNFs) on axial zC-MRMN images and axial zH-MRMN multiplanar reformation (MPR) images were compared. The nerve fascicle appearances on the longitudinal zH-MRMN MPR images were described.

Results: In the nerve segments whose long axes were perpendicular to the imaging planes of both zC-MRMN and zH-MRMN, the VSNFs were not significantly different between the axial images of the two modalities (P = 0.083). In the nerve segments whose long axes were not perpendicular to the imaging planes of zC-MRMN, the VSNFs on the axial zC-MRMN images were significantly lower than those on the axial zH-MRMN MPR images that were angled perpendicular to the long axis of the tibial nerve (P < 0.001).

Conclusions: The longitudinal zH-MRMN MPR images clearly displayed the changing features of the intraneural fascicles as well as the gross morphology of the tibial nerves. zH-MRMN can clearly delineate the topography of the tibial nerve fascicles in vivo through use of a 3T MR scanner.

Keywords: Magnetic resonance imaging; Microneurography; Multiplanar reformation; Nerve fascicle topography; Z-axis scanning.