Diagnostic Ultrasound of the Vagus Nerve in Patients with Diabetes.

Background And Purpose: Autonomic neuropathy is a serious and common complication of diabetes mellitus. The vagus nerve is the longest autonomic nerve, and may be affected in diabetes as a part of generalized neuropathy. Our objective was to assess for possible sonographic changes of the vagus nerve in diabetic patients.

Methods: The vagus nerve was bilaterally scanned in 20 healthy volunteers and 54 patients with diabetes in the axial plane at the lateral neck.

Results: The mean cross-sectional area of the vagus nerve was significantly smaller in patients with diabetes compared with controls. Receiver operating characteristic curve analyses revealed an area under the curve of .96, and an optimum cutoff point of 3 mm with a sensitivity of 85.2% and specificity of 100%.

Conclusions: This study demonstrates a degree of vagus nerve atrophy in patients with diabetes. This finding may have relevance in the diagnosis and treatment of diabetic neuropathy if further validated.