Sonographic Evaluation of the Median Nerve in Diabetic Patients

Abstract

Objective. Diabetes mellitus is becoming a major cause of premature disability in Japan, and peripheral neuropathy is a common complication of diabetes. The aim of this study was to evaluate the relationship between the results of nerve conduction studies (NCS) and the size of the nerve determined by sonography in diabetic patients. Methods. Twenty diabetic patients (mean age ± SD, 57.1 ± 13.6 years) and 20 healthy volunteers (mean, 61.1 ± 8.9 years) were enrolled in this study. Patients' wrists that had symptoms of carpal tunnel syndrome were not included in the study; those that were included had negative Phalen test results. We then divided the patients into 2 groups (patients with and without diabetic symmetric polyneuropathy [DPN]). The cross‐sectional area (CSA) was measured in the carpal tunnel 5 cm proximal to the wrist and elbow joint of the median nerve. Results. There was a significant increase in the CSA in patients with DPN in the carpal tunnel compared with the control participants (P < .01) and patients without DPN (P < .01). The CSA in the carpal tunnel showed a significant correlation with the motor nerve conduction velocity (r = −0.473). Conclusions. The CSA of the median nerve in the carpal tunnel of patients with DPN is greater than that in patients without DPN and healthy individuals and correlates with NCS.

Ultrasound Findings After Surgical Decompression of the Tarsal Tunnel in Patients With Painful Diabetic Polyneuropathy: A Prospective Randomized Study

“…Liu et al (23) found a significantly increased CSA and T/W ratio in the sural nerve in people with diabetes with neuropathy compared with people with diabetes without neuropathy and with healthy control subjects. The CSA of the median nerve in the carpal tunnel of patients with DPN was greater than without DPN and healthy control subjects (24). CSA in patients with idiopathic carpal tunnel syndrome is also greater than in control subjects (25).…”

Sonographic Imaging of the Peripheral Nerves in Patients with Type 2 Diabetes Mellitus

“…High-resolution diagnostic ultrasonography (US) has improved greatly, allowing for evaluation of minute peripheral nerves (Fornage., 1993;Solbiati et al, 1985). We previously showed that the cross-sectional area (CSA) of the median nerve in the carpal tunnel of patients with DPN is greater than that of controls and correlates with NCS (Watanabe et al, 2009). Furthermore, it appears that the percentage of the hypoechoic area of the peripheral nerves was significantly greater in patients with lower motor nerve conduction velocity (MCV) and DM than in controls or patients with higher MCV and DM (Watanabe et al, 2010).…”

Ultrasonography for the Diagnosis of Carpal Tunnel Syndrome in Diabetic Patients: Missing the Mark?

“…Experimental studies in rats showed no clear changes in the microscopic structure of nerves [14]. A more recent study did not show significant differences in the size or echogenicity of the fibular and tibial nerves in patients with diabetic PNP [15] while another study presented contradictory results such as an increase in the CSA of median nerves in patients with diabetic PNP in comparison with healthy controls [16]. Dyke et al described morphometric abnormalities in the microvessels of nerves with relation to DM [17].…”

“…Watanabe et al compared the CSA of peripheral nerves in diabetic patients with PNP and healthy volunteers. They describe an increase of the CSA in diabetic patients [16]. Based on this assumption, this paper aimed at evaluating the role of ultrasound in diabetic patients with CTS using larger cohorts than Watanabe et al…”