Three-dimensional visualization of lung blood flow heterogeneity based on fluorescent microsphere technique and fractal dimension: The Blood Flow Analysis System - BFA System

The heterogeneity of regional pulmonary blood flow (RPBF) can be assessed by fractal analysis. The fractal dimension (FD) is a scale-independent measure of spatial heterogeneity of blood flow. The relative dispersion (RD) is often used to obtain the heterogeneity of RPBF but it is influenced by the resolution of measurement. The Blood Flow Analysis (BFA) System was developed in Delphi to represent the three-dimensional structure of lung blood flow and calculates statistics of FD, RE, spatial correlation of neighbored tissue samples and shows histograms of blood flows at diverse time points during different experiments. The BFA System reads a text file with flows, measured with fluorescent microsphere technique, and constructs the: lung anatomy with volumetric pixels showing the flows with a color schema. It is possible to rotate the lungs into two axis (XY) and the statistics are shown with 3D graphics. The System maintains a database with data from various studies at same time. The BFA System was validated with four data sets fi om previous experiments. The BFA System has shown consistency and it is a new tool to help researchers during lung perfusion studies. (C) 2001 Elsevier Science Ireland Ltd. All rights reserved.