Pulmonary Transit Time Assessment by CEUS in Healthy Rabbits: Feasibility, and the Effects of UCAs Dilution Concentration

Ultrason Imaging. 2024 Apr 15:1617346241246169. doi: 10.1177/01617346241246169. Online ahead of print.ABSTRACTTo evaluate the inter-observer variability and the intra-observer repeatability of pulmonary transit time (PTT) measurement using contrast-enhanced ultrasound (CEUS) in healthy rabbits, and assess the effects of dilution concentration of ultrasound contrast agents (UCAs) on PTT. Thirteen healthy rabbits were selected, and five concentrations UCAs of 1:200, 1:100, 1:50, 1:10, and 1:1 were injected into the right ear vein. Five digital loops were obtained from the apical 4-chamber view. Four sonographers obtained PTT by plotting the TIC of right atrium (RA) and left atrium (LA) at two time points (T1 and T2). The frame counts of the first appearance of UCAs in RA and LA had excellent inter-observer agreement, with intra-class correlations (ICC) of 0.996, 0.988, respectively. The agreement of PTT among four observers was all good at five different concentrations, with an ICC of 0.758-0.873. The reproducibility of PTT obtained by four observers at T1 and T2 was performed well, with ICC of 0.888-0.961. The median inter-observer variability across 13 rabbits was 6.5% and the median variability within 14 days for 4 observers was 1.9%, 1.7%, 2.2%, 1.9%, respectively; The PTT of 13 healthy rabbits is 1.01 ± 0.18 second. The difference of PTT between five concentrations is statistically significant. The PTT obtained by a concentration of 1:200 and 1:100 were higher than that o...
Source: Ultrasonic Imaging - Category: Radiology Authors: Source Type: research