Burbank F H, Thompson W M
Invest Radiol. 1986 Mar;21(3):240-7. doi: 10.1097/00004424-198603000-00009.
Prior to the formation of an intravenous digital subtraction angiography (IV-DSA) image, contrast medium passes through the lesser circulation and is diluted by the blood volume of the heart and lungs. If the contrast medium alone influences central blood volume or cardiac output, the shape of the resultant time-concentration curve may be degraded. To the extent that contrast medium tonicity reduces curve peak or increases width, image quality for mask mode IV-DSA will suffer. To quantify the effect of contrast medium tonicity upon curve shape, contrast medium (1) at increasing iodine concentration and increasing osmolality and (2) at constant iodine concentration and increasing osmolality was injected into the right atria of mongrel dogs. In both experiments, increasing osmolality was associated with an increase in central blood volume (CBV) and cardiac output. With an increase in CBV, curve peak fell. With an increase in both CBV and cardiac output, curve width was not influenced by increasing osmolality. The effect of osmolality upon CBV was highly variable; in these experiments CBV was influenced more by subject-to-subject variability. However, on the average, higher tonicity contrast media produced curves with lower peaks. These studies suggest that isotonic contrast medium does not increase CBV and that isotonic contrast medium is preferable to hypertonic contrast medium for IV-DSA image formation.
在形成静脉数字减影血管造影（IV-DSA）图像之前，造影剂先通过小循环，然后被心脏和肺部的血容量稀释。如果仅造影剂影响中心血容量或心输出量，那么所得时间-浓度曲线的形状可能会变差。就造影剂张力降低曲线峰值或增加宽度而言，蒙片模式IV-DSA的图像质量会受到影响。为了量化造影剂张力对曲线形状的影响，将（1）碘浓度增加且渗透压增加以及（2）碘浓度恒定且渗透压增加的造影剂注入杂种犬的右心房。在这两个实验中，渗透压增加均与中心血容量（CBV）增加和心输出量增加相关。随着CBV增加，曲线峰值下降。随着CBV和心输出量两者均增加，曲线宽度不受渗透压增加的影响。渗透压对CBV的影响高度可变；在这些实验中，CBV受个体差异的影响更大。然而，平均而言，高渗造影剂产生的曲线峰值较低。这些研究表明，等渗造影剂不会增加CBV，并且对于IV-DSA图像形成，等渗造影剂优于高渗造影剂。
