Facing the diagnostic challenge: Nerve ultrasound in diabetic patients with neuropathic symptoms.

Introduction: We describe the nerve ultrasound findings in patients with type II diabetes mellitus who have neuropathic symptoms and signs.

Methods: Fifty-five healthy controls and 44 diabetic patients underwent clinical, sonographic, and electrophysiological evaluation. Patients were studied at a mean of 14.3 years after disease onset.

Results: Nerve ultrasound revealed increased cross-sectional area (CSA) in peripheral nerves at compression sites (although no clinical symptoms were present) and noncompression sites. No correlation was detected between sonographic and electrophysiological findings. A CSA increase of the tibial nerve in the popliteal fossa was detected in 5 patients with neuropathic symptoms, although electrophysiology was normal.

Conclusions: Nerve ultrasound revealed crucial morphological alterations in diabetic patients. CSA enlargement at compression sites indicates subclinical nerve affection and may indicate susceptibility to entrapment syndromes. CSA increase at noncompression sites despite normal electrophysiology suggests early morphological abnormalities. Further longitudinal studies are required to confirm our results. Muscle Nerve, 2015 Muscle Nerve 54: 18-24, 2016 Muscle Nerve 54: 18-24, 2016.