AUTHOR=Jende Johann M. E. , Kender Zoltan , Rother Christian , Alvarez-Ramos Lucia , Groener Jan B. , Pham Mirko , Morgenstern Jakob , Oikonomou Dimitrios , Hahn Artur , Juerchott Alexander , Kollmer Jennifer , Heiland Sabine , Kopf Stefan , Nawroth Peter P. , Bendszus Martin , Kurz Felix T. 

TITLE=Diabetic Polyneuropathy Is Associated With Pathomorphological Changes in Human Dorsal Root Ganglia: A Study Using 3T MR Neurography

JOURNAL=Frontiers in Neuroscience

VOLUME=14

YEAR=2020

URL=https://www.frontiersin.org/journals/neuroscience/articles/10.3389/fnins.2020.570744

DOI=10.3389/fnins.2020.570744

ISSN=1662-453X

ABSTRACT=<p>Diabetic neuropathy (DPN) is one of the most severe and yet most poorly understood complications of diabetes mellitus. <italic>In vivo</italic> imaging of dorsal root ganglia (DRG), a key structure for the understanding of DPN, has been restricted to animal studies. These have shown a correlation of decreased DRG volume with neuropathic symptom severity. Our objective was to investigate correlations of DRG morphology and signal characteristics at 3 Tesla (3T) magnetic resonance neurography (MRN) with clinical and serological data in diabetic patients with and without DPN. In this cross-sectional study, participants underwent 3T MRN of both L5 DRG using an isotropic 3D T2-weighted, fat-suppressed sequence with subsequent segmentation of DRG volume and analysis of normalized signal properties. Overall, 55 diabetes patients (66 ± 9 years; 32 men; 30 with DPN) took part in this study. DRG volume was smaller in patients with severe DPN when compared to patients with mild or moderate DPN (134.7 ± 21.86 vs 170.1 ± 49.22; <italic>p</italic> = 0.040). In DPN patients, DRG volume was negatively correlated with the neuropathy disability score (<italic>r</italic> = −0.43; 95%CI = −0.66 to −0.14; <italic>p</italic> = 0.02), a measure of neuropathy severity. DRG volume showed negative correlations with triglycerides (<italic>r</italic> = −0.40; 95%CI = −0.57 to −0.19; <italic>p</italic> = 0.006), and LDL cholesterol (<italic>r</italic> = −0.33; 95%CI = −0.51 to −0.11; <italic>p</italic> = 0.04). There was a strong positive correlation of normalized MR signal intensity (SI) with the neuropathy symptom score in the subgroup of patients with painful DPN (<italic>r</italic> = 0.80; 95%CI = 0.46 to 0.93; <italic>p</italic> = 0.005). DRG SI was positively correlated with HbA1c levels (<italic>r</italic> = 0.30; 95%CI = 0.09 to 0.50; <italic>p</italic> = 0.03) and the triglyceride/HDL ratio (<italic>r</italic> = 0.40; 95%CI = 0.19 to 0.57; <italic>p</italic> = 0.007). In this first <italic>in vivo</italic> study, we found DRG morphological degeneration and signal increase in correlation with neuropathy severity. This elucidates the potential importance of MR-based DRG assessments in studying structural and functional changes in DPN.</p>