Hesselink J R, Chang K H, Chung K J, Abbate L, Goodsitt M
AJNR Am J Neuroradiol. 1986 May-Jun;7(3):427-31.
A steady-state flow model was used to optimize methods of data analysis, to investigate variables that affect the time-density curves, and to determine the accuracy of transit-flow measurements with digital subtraction angiography. The most accurate data were obtained by using a small region of interest placed within the vessel, averaged data acquisition, and a gamma-variate fit applied to the time-density curve. The integrated area of the curve depended on the flow, vessel size, amount of iodine injected, framing rate, and the kVp. The integrated area was not affected by the mAs; the matrix size; or the volume, concentration, or rate of injection of the contrast material. Subject density, image intensifier mode, and field size did not affect the curves except for their contribution to scatter and beam hardening. There was good correlation between digital subtraction angiographic transit-flow measurements and known flow values.
采用稳态血流模型来优化数据分析方法，研究影响时间-密度曲线的变量，并确定数字减影血管造影术测量通过血流的准确性。通过在血管内放置一个小的感兴趣区域、平均数据采集以及对时间-密度曲线应用伽马变量拟合，可获得最准确的数据。曲线的积分面积取决于血流量、血管大小、注入的碘量、帧频和千伏峰值。积分面积不受毫安秒、矩阵大小、造影剂的体积、浓度或注射速率的影响。除了它们对散射和束硬化的影响外，受检者密度、影像增强器模式和视野大小不影响曲线。数字减影血管造影术测量的通过血流与已知血流值之间存在良好的相关性。
