Avneesh Chhabra MD, Presenter: Research Grant, Siemens AG Research Consultant, Siemens AG Research Grant, Integra LifeSciences Holdings Corporation Research Grant, General Electric Company Consultant, ICON plc

Sahar Jalali Farahani MBBS, Abstract Co-Author: Nothing to Disclose

Gaurav Kumar Thawait MD, Abstract Co-Author: Nothing to Disclose

John A. Carrino MD, MPH, Abstract Co-Author: Consultant, BioClinica, Inc Consultant, Pfizer Inc Advisory Board, General Electric Company

1. Evaluate the quality and feasibility of 3D whole body MR neurography (MRN) imaging. 2. Assess disease burden (nerve thickening and hyperintensity) in the diffuse known neuropathy cases and compare with controls. 3. Evaluate differences among the different types of diffuse neuropathies.  

Patients and healthy controls were all imaged on 3 Tesla MR scanner. 2-3 sets of 3D anatomic MRN (1.5mm isotropic from the base of skull to proximal thighs), contiguous axial T2W SPAIR of the symptomatic extremity, and DTI of brachial and LS plexuses was obtained with a total imaging time of upto 1hr-15 minutes. Two readers assessed the quality in consensus  and independently performed all the measurements. Nerve diameter and signal intensity ratios was measured for C5-7 nerves, L4-S1 nerves, sciatic and femoral nerves bilaterally. FA and ADC values were also measured. Tractography was obtained in all cases. Descriptive analysis and analytic methods (paired t test, weighted kappa calculation for differences) were used.  

18 subjects [7 controls (6 men, 1 women, age 28+/−3 yrs) and 11 patients with neuropathy (4 men, 7 women; mean age 45+/−4 yrs)] were studied. The diagnosis included− Charcot Marie Tooth disease (CMT) type IA (7/11), CMT type II (1/11) CMT type III: HNPP (2/11) and MMN (1/11). Most exams (95%) recieved good-excellent imaging quality. The nerve thickening was significant in LS plexus, sciatic and femoral nerves (p<0.05); while hyperintensity was significant in brachial and LS plexuses (p<0.05). The most thickening was seen in CMT type 1A. MMN showed patchy bilateral nerve thickening. Pseudomasses were seen in CMT 1A. Nerve entrapments in extremity were seen in (4/11) cases. Mean left to right differences in DTI values were not significantly different. ADC of brachial plexus, LS plexus and FA values of LS plexus were significant (p<0.05). Tractography differences were observed among normal and abnormal subjects. Interobserver performance was good to excellent.

Whole body MRN is feasible method with good to excellent interobserver performance that can be objectively used to evaluate disease burden and detect differences among diffuse neuropathies.  

Whole body MR neurography is a non invasive method that can be applied to diffuse neuropathy cases to evaluate the disease burden, differentiate among various causes of diffuse neuropathy and to detect superimposed entrapments.

Chhabra, A, Farahani, S, Thawait, G, Carrino, J, Whole Body MR Neurography - Initial Results.  Radiological Society of North America 2014 Scientific Assembly and Annual Meeting, - ,Chicago IL. http://archive.rsna.org/2014/14012103.html