Supplementary Materials Supplementary Data supp_32_5_646__index. GPR44 sectioned and stained with haematoxylin and eosin and von-Willebrand factor. Adventitial vasa vasorum density was quantified by counting the amount of stained microvessels and their total cross-sectional region. Plaque size (per cent lumen area) progressed over time ( 0.001), as did adventitial vasa vasorum density ( 0.001). Plateau peak videointensity also progressed, demonstrating a strong linear correlation with histologic vasa vasorum density ( 0.001). Receiver operating characteristic analysis indicated that a three-fold increase in median adventitial videointensity had a sensitivity of 100% and specificity of 88% for predicting abnormal neovascularization. Conclusion We have histologically validated that CUS quantifies the development of adventitial vasa vasorum associated with atherosclerosis progression. This imaging technique has the potential for characterizing prognostically significant plaque features. are limited. Recently, contrast ultrasound (CUS) has emerged as a method for imaging vasa vasorum.17C22 Observational CUS studies of patients with carotid disease have shown acoustic activity within and around plaques and a semiquantitative correlation with endarterectomy specimens.17,18,20 The ability of CUS, however, to be Cyclosporin A inhibition quantitative and to serially follow vasa vasorum density over the time course of plaque evolution, has not been established. Indeed, further validation of this method for quantifying vasa vasorum is usually a pre-requisite to its clinical application. Accordingly, in the present study, we tested the hypothesis that CUS can quantify vasa vasorum during atherosclerosis progression. Serial femoral artery CUS imaging was performed in a rabbit model of atherosclerosis, with post-mortem histologic analysis as the reference standard. Methods Animal model of accelerated atherosclerosis A rabbit model of accelerated atherosclerosis was used.23 Twenty New Zealand white rabbits (3.5C4 kg) were fed a high-fat, high-cholesterol diet (peanut oil 2.5%, cholesterol 1%, fat 10%) for 3 weeks. Seven days after commencing the dietary plan, rabbits had been anaesthetized with ketamine (150 mg IM) and xylazine (8 mg IM) and 2.5% inhaled isofluorane. An ear canal vein was cannulated for ultrasound comparison administration. A 2F Fogarty balloon catheter was released to the superficial femoral artery, advanced in to the common femoral artery, inflated at 2 atm and advanced and withdrawn 3 x to induce damage. This process was repeated in the contralateral femoral artery, the catheter was taken out, and the rabbits recovered. Comparison ultrasound imaging Comparison ultrasound of the femoral artery was performed using Definity (diameter 1C4 m, Lantheus Medical Imaging) as the comparison agent. Rabbits had been intravenously administered a 0.2 mL contrast bolus over 10 s during nonlinear (10 MHz Contrast Pulse Sequence) imaging of the femoral artery in the longitudinal plane (Sequoia, Siemens). Comparison pulse sequencing is certainly a multi-pulse imaging technique utilizing stage and amplitude modulation of the transmit ultrasound coupled with cancellation algorithms to detect microbubble-specific indicators. After a higher power burst body (mechanical index (MI) of just one 1.9) to destroy microbubbles, real-period ultrasound imaging (MI 0.3) was performed to fully capture microbubble reflow in to the femoral artery lumen and vasa vasorum. The quality of our ultrasound imaging program is certainly 0.15 mm, with a dynamic selection of 75 dB. Digitally obtained ultrasound images had been analysed off-range using personalized CUS software program by an observer blinded to experimental condition. Videointensity in each body was measured in an area of interest used the adventitia of the wounded vessel segment. Videointensity data, which relate with the focus of microbubbles in cells, had been plotted against period elapsed from the destruction pulse and suit to a previously referred to monoexponential function: = = videointensity, = time, = price of microbubble replenishment (red blood cellular velocity), and = peak plateau strength (microvascular cross-sectional region).24 Adventitial peak videointensity was normalized to the peak videointensity measured in a luminal region of curiosity drawn proximal to the region of balloon injury. Histological evaluation On the ultimate time of the experiment, both femoral arteries Cyclosporin A inhibition had been perfusion-set using paraformaldehyde infused in to the abdominal aorta, excised and paraffin-embedded, and cross-sections had been stained for light microscopy (IX81, Olympus) with haematoxylin and eosin (H&Electronic) and von-Willebrand aspect (vWF) for endothelium. Extra sections had been frozen and stained for macrophages (RAM11) and KDR receptors for Cyclosporin A inhibition vascular endothelial development aspect (VEGF) (CVPath Institute, Inc.; Gaithersburg, MD). Vasa vasorum on digitized pictures had been quantified by counting the full total amount of vWF-positive microvessels per femoral artery cross-section, along with their total cross-sectional region (CSA), that was measured by planimetry (Image J software program,.