High resolution ultrasonography of peripheral nerves in diabetic peripheral neuropathy

Purpose: The purpose of the study was to assess the usefulness of high-resolution ultrasonography (HRU) in the evaluation of diabetic peripheral neuropathy (DPN). Methods: Thirty-seven adult diabetic patients with clinically diagnosed DPN and 45 healthy adult volunteers were included in the study. HRU of the right medial, ulnar, common peroneal, and posterior tibial nerves was done. The mean cross-sectional area (CSA) of the involved nerves was measured in the two groups at identical positions. The CSA was compared between the two groups, and Student t-test was applied to assess statistical significance. Results: There was a significant increase in the CSA of the median, ulnar, common peroneal, and posterior tibial nerve in DPN patients as compared to healthy volunteers. Sonographic findings were compared with nerve conduction study (NCS) for all the nerves studied except common peroneal nerve (CPN), as the NCS of CPN is not routinely done. DPN was classified as mild or moderate to severe on the basis of latency and velocity assessed by NCS. The mean CSA in all the examined nerves was higher in moderate to severe DPN than the mild DPN, but this was not statistically significant except for ulnar nerve with a P value of < 0.0001. Conclusion: HRU demonstrates a morphological change in patients with DPN in the form of an increase in CSAs, which was statistically significant. HRU can objectively complement other diagnostic investigations such as NCS. High resolution ultrasonography of peripheral nerves has the potential to become the investigation of first choice for the evaluation of DPN.