论文信息 - Evidence for spleen-specific uptake of a microbubble contrast agent: a quantitative study in healthy volunteers.

Evidence for spleen-specific uptake of a microbubble contrast agent: a quantitative study in healthy volunteers.

PURPOSE To evaluate the pharmacokinetics of the microbubble contrast agent BR1. MATERIALS AND METHODS Twenty healthy volunteers were injected via arm vein with a 1.2-mL bolus of BR1. Ultrasonographic images of liver and right kidney and of spleen and left kidney were obtained intermittently for 5 minutes with low-mechanical-index software (to minimize microbubble destruction) that shows stationary microbubbles in green. Percentage total uptake was calculated as the number of green pixels in the region of interest for each organ over time, divided by the total pixels. Relative uptake, the ratio of total uptake in liver to that in right kidney and of total uptake in spleen to that in left kidney, and differential uptake, the difference in total uptake between liver and right kidney and between spleen and left kidney, were calculated. Total uptake for each organ was plotted against time, and the gradient of a best-fit straight line was calculated. Wilcoxon signed rank test was used to compare mean uptake values in each subject. Mann-Whitney U test was used for comparisons in sex and age. RESULTS Total uptake declined over 5 minutes in left and right kidney and in liver (from 88% +/- 10% [1 minute] to 67% +/- 14% [5 minutes]), but not in spleen (range, 90%-99%). Mean relative uptake +/- 1 SD for spleen increased from 2.3 +/- 0.7 (1 minute) to 3.7 +/- 2.3 (5 minutes) (P =.005) but for liver was constant: 2.1 +/- 0.9 (1 minute) and 2.3 +/- 0.4 (5 minutes) (P =.06). Mean differential uptake +/- 1 SD for spleen increased from 51.3% +/- 14.9% (1 minute) to 65.0% +/- 9.1% (5 minutes) (P =.002). Significant difference was seen over time in total uptake gradients between spleen and left kidney (P =.014) but not between liver and right kidney or right and left kidney. No difference was seen between men and women or with age. CONCLUSION BR1 produces spleen-specific enhancement that is longer (5 minutes) than the blood pool phase.

[1] Michel Claudon,et al. Ultrasound contrast agents: properties, principles of action, tolerance, and artifacts , 2001, European Radiology.

[2] R. E. Person,et al. Hepatic lesion differentiated from accessory spleen by a heat-damaged red blood cell scan. , 2000, Clinical nuclear medicine.

[3] B. Goldberg,et al. Tissue-specific US contrast agent for evaluation of hepatic and splenic parenchyma. , 1999, Radiology.

[4] A. Broillet,et al. Gray-scale liver enhancement in VX2 tumor-bearing rabbits using BR14, a new ultrasonographic contrast agent. , 1997, Investigative radiology.

[5] G. Schmid-Schönbein,et al. Mechanism of parenchymal enhancement of the liver with a microbubble-based US contrast medium: an intravital microscopy study in rats. , 2002, Radiology.

[6] M. D. Massey,et al. Residual spleen found on denatured red blood cell scan following negative colloid scans. , 1991, Journal of nuclear medicine : official publication, Society of Nuclear Medicine.

[7] Feng Yan,et al. BR1: A New Ultrasonographic Contrast Agent Based on Sulfur Hexafluoride-Filled Microbubbles , 1995, Investigative radiology.

[8] Robert J. Eckersley,et al. Developments in ultrasound contrast media , 2001, European Radiology.

[9] D O Cosgrove,et al. Stimulated acoustic emission to image a late liver and spleen-specific phase of Levovist in normal volunteers and patients with and without liver disease. , 1999, Ultrasound in medicine & biology.