Spectrum of High Resolution Ultrasonography and Color Doppler Findings in Peripheral Neuropathy

Abstract

Background: Available diagnostic modalities for peripheral neuropathies e.g clinical assessment, electrodiagnostics, skin and nerve biopsy has certain limitations. The role of imaging is very limited. Purpose of this study is to evaluate findings in various peripheral neuropathies on ultrasonography and color Doppler. Subjects and Methods: Fifty adult patients of either sex with already diagnosed peripheral neuropathies were evaluated with high resolution ultrasound and color doppler of the relevant peripheral nerves and were compared with age and sex matched fifty healthy adult controls. Results: The study included patients with various peripheral neuropathies (carpal tunnel syndrome, diabetic peripheral neuropathy, leprosy, chronic inflammatory demyelinating polyradiculoneuropathy, and peripheral nerve trauma). There was a significant increase in cross sectional area and change in echogenicity of median nerve at carpal tunnel in carpal tunnel syndrome (p<0.05). Multiple nerves in diabetic peripheral neuropathy and leprosy patients showed increased cross sectional area and altered echogenicity as compared to controls (P < 0.05). Patients with CIDP showed diffusely hyperechoic peripheral nerves. Sonography in peripheral nerve trauma showed significant hyperechogenicity and increased vascularity on doppler at site of trauma with precise localization. Conclusion: High resolution ultrasonography with color doppler showed greater extent of quantitative and qualitative alterations in peripheral nerves in various peripheral neuropathies.  USG has the potential to complement other diagnostic investigations such as the nerve conduction study in polyneuropathies and can objectively measure nerve damage in some focal neuropathies. It is easily available and has the potential to become the first modality for screening or evaluation of peripheral neuropathies.