Analysis of blood and dialysate flow in a hemodialyzer by perfusion computed tomography

Abstract

Perfusion computed tomography (PCT) is a means to rapidly and easily evaluate cerebral perfusion in patients presenting with acute stroke symptoms, which pro-vides insights into capillary-level hemodynamics. In this study, we used PCT to analyze the 3-dimensional blood and dialysate flow in a low-flux hemodialyzer equipped with a standard fiber bundle. The dynamic CT studies were performed with 64-channel multi-detector row CT (MDCT) at a dialysate flow rate of 500 ml/min and a 1.0 ml/sec injection rate of contrast agent. Central volume principle was used to calculate hydro-dynamic parameters by deconvolution of time-density curves (TDCs). Functional maps of PCT parameters quantitatively described the blood and dialysate flow maldistribution, varia-tions in fiber packing, and perfusion pressure distribution in a hemodialyzer. PCT was able to overcome the limitations of conventional imaging techniques for analyzing dialysate flow distributions in hollow-fiber dialyzers. Therefore, PCT is a quantitative analysis method to provide better insights into hemodynamics of hollow-fiber dialyzers and is expected to contribute to optimization of artificial kidneys. © 2009 Springer-Verlag.