Estimation of Mean Radius, Length and Density of Microvasculature Using Diffusion and Perfusion MRI
نویسندگان
1 Department of Mechanical Engineering,Sharif University of Technology
doi
چکیده
In theory, di usion and perfusion information in MRI maps can be combined to yield morphological information, such as capillary density, volume and possibly capillary plasma velocity. This paper suggests a new method for determination of mean radius, length and capillary density in normal regions using di usion and perfusion MRI. Mean Transit Time (MTT), Cerebral Blood Volume (CBV), Apparent Di usion Coecient (ADC), pseudo-di usion coecient (D) and R2 and R 2 values were utilized to calculate mean radius, length and capillary density. To verify the proposed theory, a special protocol was designed and tested on normal regions of a male Wistar rat using obtained functions. Mean radius, length and capillary density in the normal regions were calculated to be 2:48 0:35 (mean SD), 234 12 microns and 11897 219=mm3, respectively. With respect to the values 0.01 through 0.1 for the CBV/Vol(voxel) parameter and 1 through 1000 sec for R2 2 =R3 2, the mean radius of the capillary, using the proposed method, varied from 0.076 to 7.58 microns.
