New blood flow measurement method using color Doppler signals -estimating its validity using phantom and mesuring in surface vessels and abdominal arteries-

常规地，通过将血管的横截面积乘以由脉冲多普勒方法确定的通过该面积的最大流速，然后通过用特定系数校正乘积来进行流量的超声估计。然而，这种方法有一些困难。我们使用一个幻影和狗检查的有效性的一个新的流量测量彩色流量signals.The方法首先涉及到一个形成的速度剖面线，通过血管的中心，这是垂直于血管的长轴。然后，血管的横截面被认为是圆形的，轮廓被发展成二维分布。在这样做时，线性轮廓的每一半被不同地处理，以避免可能由偏心峰带来的误差。因此，可以通过将每个速度乘以该速度中的像素数并将乘积相加来计算给定时刻的流量。然后，可以通过对每个心动周期的流量进行积分来计算每个心动周期的流量。由此得到的结果显示出良好的相关性与实际流量不仅通过模体，而且狗（r=0.9）。门静脉主干和右前分支的血流曲线均呈峰形扁平，而脉冲多普勒法显示的是抛物线型。用彩色多普勒方法测量门静脉左分支的螺旋血流，并用此方法测量颈动脉的切变率。无创性显示血管壁附近的高比率和血管中心的低比率。

Ultrasonic estimation of flow volume has conventionally been made by multiplying a cross-sectional area of a vessel by a maximum flow velocity through the area as determined by pulsed Doppler method and then by correcting the product by a certain coefficient. This method, however, have some difficulties. We examined using a phantom and a dog the validity of a new flow volume measurement by color flow signals.The method firstly involved a formation of a velocity profile on a line that passes the center of a vessel and that is perpendicular to the long axis of the vessel. Then the cross section of the vessel being deemed circular, the profile is developed into a two-dimensional distribution. In doing so, each half of the linear profile are treated differently to avoid an error that might be brought by an eccentric peak. A flow volume at a given moment can thus be calculated by multiplying each velocity by number of pixels in that velocity and by adding up the products. A flow volume per one cardiac cycle can then be calculated by integrating flow volumes at amount for the cycle. Results thus obtained showed a good correlation with those of the actual flow volume through not only the phantom but also a dog (r=0.9).We also estimated portal venous flow. The flow profiles in the main portal vein and right anterior branch were depicted peak flattening shaped, which was previously reported parabolic by the pulsed Doppler method. Estimating by color Doppler method, spiral flow was demonstraed in the left branch of the potal vein.Shear rate of the carotid artery are estimated by using this methos. They revealed high ratio near the wall and low ratio center of the vessels non-invasively.