Arterial diameter change measurements in premature rabbit pups using B-Mode images

To further promote cardiovascular research there is a growing need for arterial characterization on small animals. Arterial wall movement measurements form the basis for most stiffness related parameters. As far as we know, previous reports on lumen diameter change measurements in small animals have required ECG triggering and cross-correlation techniques on the RF-signal using extremely high frame rate. The first aim of this study was to evaluate a novel method, ARTerIal Characterization (ARTIC), for robust diameter measurements in premature rabbit pups using conventional scanning technique (B-mode, 230 Hz). Although blood pressure is important for arterial stiffness measurements, it is often impossible to obtain without affecting the animal setup. However, arterial stiffness can also be assessed by measuring the pressure independent transition strain as recently proposed by Danpinid et al. (Ultrasonics 50, 2010:654-665). The second aim was to investigate the feasibility of measuring transition strain in premature rabbit pups using the obtained diameter curve. The diameter was 874/82 m (mean/SD), CV 2.9%. The distension was 24±3 m, CV 7.3%. The transition strain was 1.55±0.46%, CV 12.8%. In summary, ARTIC can measure arterial diameter and distension in small animals using B-Mode images at regular frame rates. ARTIC also has a low computation time suitable for real-time implementation. Measurements of transition strain on premature rabbit pups are feasible using B-Mode images at regular frame rate.