Correlation between Quantitative Ultrasonography on Small Muscles of the Foot in Diabetic Peripheral Neuropathy and Electrodiagnostic Study

Abstract Background: DPN is worthy of study as it's a leading cause for disability due to foot ulceration and amputation, gait disturbance, and fall-related injury. That makes the early diagnosis of DPN invaluable. Aim of Study: To assess the correlation between quantita-tive muscle ultrasonography (US) findings and electrodiag-nostic study results in patients with diabetic peripheral neu-ropathy (DPN). The clinical importance of quantitative muscle US in DPN was also evaluated. Patients and Methods: Twenty-five patients with DPN and 25 healthy volunteers were recruited. All control and DPN subjects underwent a bilateral peroneal and tibial motor nerve conduction study (NCS) and quantitative muscle US. Ultrasound images of the abductor haullicis (AH) muscle and the extensor digitorum brevis (EDB) muscle were obtained to measure thickness, muscle cross-sectional area (CSA) and echo intensity (EI). Differences in muscle thickness, CSA, and EI between the control and DPN patients' groups were analyzed. Relationships between electrodiagnostic study results and quantitative US parameters were evaluated. Results: A close relations observed between US findings (EI, CSA and muscle thickness) and NCS neuro-physiological findings indicating that we can use both examinations to detect muscle atrophy, and that US can expect changes in neurophys-iologic parameters in diabetics (muscle thickness and CSA were decreased, and EI was increased). The findings in the peroneal nerve were more significant than those in tibial nerve. Comparison between cases and controls regarding quantitative muscle US revealed a statistically insignificant difference in most the parameters, but some parameters showed statistically significant difference. However, there was a clinical importance of the US examination despite the insig-nificant statistics.
Conclusion: These findings suggest that quantitative muscle ultrasound may be useful for detecting muscle changes in DPN. Further studies are needed to confirm the findings in larger groups of diabetic patients and to evaluate peripheral muscles by using quantitative muscle US in other types of neuropathy and neuromuscular diseases.