Evaluation of peripheral neuropathy of lower limbs in patients with type 2 diabetes mellitus by high-frequency ultrasonography

Abstract

Objective To observe the abnormalities of femoral and saphenous nerves in patients of type 2 diabetes mellitus (T2DM) with or without diabetic periphery neuropathy (DPN) by high-frequency ultrasonography. Methods Eighty-one T2DM patients were enrolled and divided into 2 groups: group B (T2DM without DPN, N = 40), group C (T2DM with DPN, N = 41). Forty-two healthy subjects were enrolled as control group (group A). LOGIQ-E9 color Doppler ultrasound instrument was used. Between inguinal ligment and inguinal fold, the femoral nerve was slightly hyperechoic with reticular structure near by the femoral artery on transverse section. In the inner thigh, the saphenous nerve was slightly hyperechoic with reticular structure along with adductor canal on transverse section. The internal echo and succession of the two nerves in 3 groups were observed. The width, thickness and cross-sectional areas of the two nerves were measured and compared. Results In group A, the internal echo of the two nerves appeared as slightly hyperechoic with reticular structure on transverse section, and strips of hypoechogenicity and parallel structure of slightly hyperechogenicity on longitudinal section. Compared with group A, the internal echo of group B was decreased slightly, and the reticular structure was slightly obscure and strips of echo on longitudinal section were less clear; while the internal echo of group C was decreased obviously, the reticular structure was not clear and strips of echo on longitudinal section were obscure. Compared with group A, both the width ( P = 0.000, for all), thickness ( P = 0.023, 0.036) and cross-sectional area ( P = 0.000, for all) of femoral nerve and the width ( P = 0.010, 0.014), thickness ( P = 0.001, for all) and cross-sectional area ( P = 0.002, 0.004) of saphenous nerve in group B and C were increased. Besides, compared with group B, thickness ( P = 0.048, 0.012) and cross-sectional area ( P = 0.031, 0.034) of femoral and saphenous nerves in group C were increased. Conclusions The abnormalities of internal echo and measurement of the trunk of femoral and saphenous nerves in patients of T2DM with or without DPN can be displayed clearly by high-frequency ultrasonography. It can provide objective basis for clinical diagnosis with great significance. doi: 10.3969/j.issn.1672-6731.2014.04.015