Ultra–high‐frequency ultrasound imaging of sural nerve: A comparative study with nerve biopsy in progressive neuropathies

Nerve ultrasound has been used increasingly in clinical practice as a complementary test for diagnostic assessment of neuropathies, but nerve biopsy remains invaluable in certain cases. The aim of this study was to compare ultra–high-frequency ultra- sound (UHF-US) to histologic findings in progressive polyneuropathies. Ten patients with severe, progressive neuropathies underwent ultrasound evaluation of the sural nerve before nerve biopsy. Ultrasound data were compared with histologic results in a retrospective manner. Sural nerves were easily identified on UHF-US. Nerve hyper- echogenicity correlated with inflammatory infiltrates on biopsy. Nerve fascicles could be identified and measured on ultrasound in the majority of patients. Hyper- echogenicity on UHF-US may be a marker of nerve inflammation in neuropathies. Furthermore, the UHF-US probe allows for evaluation of sensory nerves in spite of their small size, providing valuable information on their size and on their internal structure.