Tessa Buckle PhD, Presenter: Nothing to Disclose

Berit Michaela Verbist MD, Abstract Co-Author: Nothing to Disclose

Thijs Engelen BSC, Abstract Co-Author: Nothing to Disclose

Martijn J.A. Malessy MD, PhD, Abstract Co-Author: Nothing to Disclose

Fijs Willon Bernard van Leeuwen PhD, Abstract Co-Author: Nothing to Disclose

Nerve damage to the cervical or brachial plexus results in reduced sensory and/or motor function. Neuron cell death is related to a decrease in volume of the dorsal root ganglion (DRG). The purpose of this study is to evaluate the use of D-prep MR neurography (MRN) for specific visualization of (damaged) nerves. Morphological features and variations in the DRGs and nerves of the cervical and brachial plexus were assessed in healthy volunteers and patients with tumor or trauma of the plexus.

Five healthy volunteers and six patients (nerve tumor (n=3) or brachial plexus lesion (located at C8; n=3)) underwent an MRI of the cervical and/or brachial plexus (3T; Philips Ingenia) using a D-prep MRN sequence. A standard T2 STIR was acquired for anatomical reference. The DRGs from C1 through C8 and nerves of the cervical and brachial plexus were assessed for their detectability and dimensions.

(Volumetric) measurements were feasible in all patients and volunteers. DRGs of (especially at the cervical plexus) were more clearly visualized with D-prep MRN compared to T2 STIR. In the volunteers DRG volume increased from 30 mm3 in C2-C4 to 180 mm3 in C7-C8. Spinal nerves of the cervical plexus (C1-C4; diameter 19.1 +/- 3.6 mm) and/or brachial plexus (C5-C8; diameter 39.7 +/- 4.8 mm) could be accurately visualized, and traced downward from their ganglion (Figure 1). Nerve trauma did not affect nerve diameter but resulted in a decrease in DRG volume (26 +/- 7%) at C8, compared to the contralateral side and C7. Tumor invasion and localized edema prohibited DRG and nerve measurements when located in close proximity to tumor, while the dimensions of unaffected nerves and DRGs were comparable to the measurements in healthy volunteers.

Measurement of the diameter of cervical nerves and the volume of their DRGs was feasible with D-prep MRN in both healthy volunteers and patients with either a nerve tumor or neuropathy after trauma. Volumetric measurements showed a decrease in DRG volume after trauma, while the diameter of the nerve was not affected.

Morphologic evaluation of nerves based on nerve specific MRI can potentially provide a non-invasive in vivo measure of the degree of functional recuperation after damage to the cervical of brachial plexus.

Buckle, T, Verbist, B, Engelen, T, Malessy, M, van Leeuwen, F, Volumetric Evaluation of the Dorsal Root Ganglia and Nerves in the Cervical and Brachial Plexus Using Nerve Specific MRI.  Radiological Society of North America 2014 Scientific Assembly and Annual Meeting, - ,Chicago IL. http://archive.rsna.org/2014/14045444.html