MECHANISMS THAT CONTRIBUTE TO THE IN-VITRO RELAXATION AND SIGNAL INTENSITY OF WATER IN BARIUM-SULFATE SUSPENSIONS USED AS MRI CONTRAST AGENTS

被引：9

作者：

BRIGGS, RW

LIEBIG, T

BALLINGER, JR

ROS, PR

机构：

[1] Department of Radiology, University of Florida College of Medicine, Gainesville

[2] Department of Chemistry, University of Florida College of Medicine, Gainesville

[3] Department of Biochemistry and Molecular Biology, University of Florida College of Medicine, Gainesville

[4] Medizinische Hochschule Hannover, 3000 Hannover, Konstanty-Gutschow-Str

来源：

MAGNETIC RESONANCE IMAGING | 1993年 / 11卷 / 05期

关键词：

BARIUM SULFATE; RELAXATION; DIFFUSION; CONTRAST AGENT; MAGNETIC SUSCEPTIBILITY;

D O I：

10.1016/0730-725X(93)90005-X

中图分类号：

R8 [特种医学]; R445 [影像诊断学];

学科分类号：

1002 ; 100207 ; 1009 ;

摘要：

The individual components of two commercially available barium sulfate (BaSO4) suspensions, Liquid HD and E-Z-paque (E-Z-EM Inc., Westbury, NY), were investigated to determine their contribution to relaxation. Longitudinal and transverse relaxation times of suspensions and solutions of the different BaSO4 particles and the vehicle used to keep them in suspension were measured separately at 2.0 T. A multiple echo Carr-Purcell-Meiboom-Gill (CPMG) pulse sequence was used for T2 determinations with different values of the echo spacing 2tau. Longer values of 2tau resulted in significant shortening of the calculated T2 relaxation times, indicating that the major mechanism leading to signal loss in BaSO4 suspensions is the diffusion of water molecules through susceptibility gradients in the vicinity of suspended particles. At higher BaSO4 concentrations, decreased water proton density also produces significant signal loss. Viscosity has little effect on the relaxation. A combination of larger and smaller BaSO4 particle sizes was found to be more effective than smaller sizes only in enhancing signal decay.

引用

页码：635 / 644

页数：10

共 33 条

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