Neuromuscular ultrasound and nerve conduction studies as complementary tools for screening of diabetic peripheral neuropathy.

Diabetic Polyneuropathy (DPN) is a common debilitating complication of Diabetes Mellitus (DM), causing pain which may progress to numbness and motor involvement. DPN may lead to diabetic foot ulcers and possible amputation. Thus, DPN affects the patients' quality of life and poses a financial burden if not managed early. Nerve conduction studies (NCS) have been used as an objective method for diagnosis of DPN. Neuromuscular Ultrasound (NMUS) is a more comfortable tool used to complement NCS in diagnosis of many diseases. The study aimed to investigate NMUS as a possible screening tool for DPN. The study included 58 patients with Type-II DM who were divided into two groups according to presence/absence of DPN using the modified Toronto clinical neuropathy score (mTCNS). The cross-sectional area (CSA) and muscle thickness (MT) in the upper and lower limbs as well as their corresponding NCS were compared. CSA of posterior tibial nerve and the sural nerve were significantly larger in the group with DPN. A cut-off value 2 mm2 CSA of the sural nerve showed sensitivity of 93.33%, specificity of 64.29% and area under the curve (AUC) was 80% for detecting DPN. This may be used as a complementary tool in certain situations to the corresponding NCS. Disease duration, HbA1c and mTCNS showed a positive correlation with NMUS findings. Patients with microvascular complications showed a significantly larger CSA of some nerves and less MT as compared to those without. NMUS represents a complementary tool to NCS and may be used for screening DPN.