Analysis of muscle microcirculation in advanced diabetes mellitus by contrast enhanced ultrasound

Aims: Contrast enhanced ultrasound (CEUS) was recently established to quantify perfusion deficits in peripheral arterial disease (PAD). However, this approach was not suitable to assess microangiopathy of skeletal muscle, a major contributor to PAD in diabetic patients. We hypothesized that an optimized methodology would detect impaired microcirculation. Methods: Ten patients with advanced diabetes mellitus (mean diabetes duration 21 years), 10 PAD patients, and 10 control subjects were enrolled consecutively. The arrival times of the contrast agent Sonovue (TM) after intravenous injection were assessed selectively in a small artery, muscle tissue and a muscle vein of the calf muscle. Contrast transit times (CTTs) were calculated as the differences between arrival times. Results: The median CTT for artery-vein was significantly higher in the diabetes group (43 s) than in the PAD (22 s, p = 0.007) and control groups (11 s, p < 0.001, no value overlap). CTTs for artery-muscle and muscle-vein were shorter with highest median values in the diabetes group. Conclusions: We validated improved CEUS as consistent method to detect changes in the microvascular bed. This method may become a valuable tool to quantify impaired microcirculation in diabetes and help to improve patient care. (C) 2008 Elsevier Ireland Ltd. All rights reserved.