Lichtenstein O, Martínez-Val R, Méndez J, Castillo-Olivares J L
Life Support Syst. 1986 Apr-Jun;4(2):141-9.
The hydrogen bubble technique was used to visualize flow past two different aortic valve prostheses. The results reported in this paper clearly show the efficacy of the method and its main advantage, namely that tracers can be produced at any position and at a completely controlled rate. This fact allows the study of either selected moments or regions of the flow field, thus enhancing contrast and therefore increasing the signal-to-noise ratio of the picture. The possible perturbations introduced by the cathode may be decreased to a minimum by using small-diameter wires or wall flush-mounted thin plates. On the other hand, the buoyant velocity of the bubbles may be only a few percent of the fluid velocity and therefore not substantially affect the results. Within the limited scope of the present investigation, the xenographic valve seems to disturb the flow significantly less than the Björk-Shiley prosthesis, both for steady and pulsatile flow, as shown by the traverse velocity profiles or through turbulent stress mapping.
采用氢气泡技术可视化流经两种不同主动脉瓣假体的血流。本文报道的结果清楚地表明了该方法的有效性及其主要优点，即示踪剂可以在任何位置以完全可控的速率产生。这一事实使得能够对流场的选定时刻或区域进行研究，从而增强对比度，进而提高图像的信噪比。通过使用小直径导线或壁面齐平安装的薄板，可以将阴极引入的可能扰动降至最低。另一方面，气泡的浮力速度可能仅为流体速度的百分之几，因此不会对结果产生实质性影响。在本研究的有限范围内，如横向速度剖面或湍流应力映射所示，无论是稳定流还是脉动流，异种瓣膜对血流的干扰似乎都明显小于比约克-希利假体。
