Patent ID: 6539245
Filing Date: 2003-03-25
Classification: A61B,G01R

Abstract:
A biomagnetic field measuring method comprising the steps of:(1) measuring a magnetic field component (Br (&thgr;, &phgr;, t)) in an r axis direction of a biomagnetic field generated from a source within a living body by using a plurality of fluxmeters disposed in parallel to a tangential plane of a surface of a semi-sphere, each fluxmeter including a superconducting quantum interference device (SQUID), wherein a radius of said semi-sphere is set on the assumption that a shape of said source is a sphere having a center which coincides with the center of said semi-sphere and coincides with an origin of the polar coordinate system (r, &thgr;, &phgr;), the r axis direction is perpendicular to the surface of said semi-sphere, and tangential components (B&thgr; (&thgr;, &phgr;, t), B&phgr; (&thgr;, &phgr;, t)) parallel to the surface of said semi-sphere of said biomagnetic field from said source are estimated from said magnetic field component (B&thgr; (&thgr;, &phgr;, t)) in the r axis direction; (2) determining a value proportional to a root of S(&thgr;, &phgr;, t)={(&dgr;Br (&thgr;, &phgr;, t)/&dgr;&thgr;)2+(&dgr;Br (&thgr;, &phgr;, t)/&dgr;&phgr;)2}from said magnetic field component (Br (&thgr;, &phgr;, t)) in the r axis direction, and determining an isomagnetic field map obtained by connecting points at which said values proportional to said root are equal to each other; and(3) displaying said isomagnetic field map.