Biomagnetic field measurement apparatus

A biomagnetic field measurement apparatus comprising:

• a plurality of magnetometers each detecting magnetic field generated from a subject to be inspected;
• a cryostat which has a cylindrical outer surface and holds the magnetometers at a low temperature by a cooling liquid;
• a guard portion which is integrally formed with the cryostat at the cylindrical outer surface;
• a member holding the cryostat, said member having an upper plate portion which has a hole having a curvature;
• a spherical moving member which has a shape of a part of sphere and a preselected thickness, wherein the spherical part of the spherical moving member has the same curvature as that of the hole of the upper plate portion, the guard portion is fixed to an upper flat portion of the spherical moving member by a fixing screw, and the spherical part of the spherical moving member is disposed in the hole of the upper plate portion such that the spherical part of the spherical moving member can freely be rotated in the hole of the user plate portion;
• two handles, each of which is disposed on the cylindrical outer surface for setting an angle of a central axis of the cryostat in respective of two perpendicular planes;
• and
• two stoppers each of which is disposed at the upper plate portion and fixes the rotation of the angle of the central axis of the cryostat in respective of two perpendicular planes.

A biomagnetic field measurement apparatus comprising:

• a plurality of magnetometers each detecting magnetic field generated from a subject to be inspected;
• and
• a cryostat which holds the magnetometers at a low temperature by a cooling liquid,
• wherein a member having humidity is disposed on a part of the cryostat, or a heating member is disposed on a part of the cryostat.

A biomagnetic field measurement apparatus comprising:

• a plurality of magnetometers each detecting magnetic field generated from a subject to be inspected;
• and
• a cryostat which holds the magnetometers at a low temperature by a cooling liquid,
• wherein a member for filling a gas generated from the cooling liquid in the cryostat at an upper part of the cryostat, the member is disposed at a part of the cryostat.

A biomagnetic field measurement apparatus comprising:

• a plurality of magnetometers each detecting magnetic field generated from a subject to be inspected;
• a cryostat which holds the magnetometers at a low temperature by a cooling liquid;
• and
• a member holding the cryostat,
• wherein, in the cryostat, a first tube for introducing the cooling liquid into the cryostat and a second tube which has a shape of a funnel tube at one end and into which one end of the first tube can be inserted.

A biomagnetic field measurement apparatus comprising:

• a plurality of magnetometers each having a SQUID sensor and a detection coil and each detecting magnetic field generated from a subject to be inspected;
• a cryostat which holds the magnetometers at a low temperature by a cooling liquid;
• a holding member which holds the cryostat such that the cryostat can be rotatable about axis of the cryostat;
• a position fitting member which has a shape same as a part of a shape including a center of a bottom surface of the cryostat and has a plurality of poles for contacting to a peripheral surface at near the bottom surface of the cryostat;
• and
• a weight marker which is connected to the position fitting member by string, at a position of the weight marker corresponding to the center of the bottom surface of the cryostat,
• wherein a plurality of indicating lines for discriminating a rotating direction of the cryostat are indicated at the bottom surface of the cryostat and at the peripheral surface at near the bottom surface of the cryostat, and the position fitting member is used for fitting the center of a bottom surface of the cryostat to a predetermined surface position of the subject to be inspected.

A biomagnetic field measurement apparatus comprising:

• a plurality of magnetometers each having a SQUID sensor and a detection coil and each detecting magnetic field generated from a heart of a fetus in a pregnant woman;
• a cryostat which holds the magnetometers at a low temperature by a cooling liquid, one ends of the magnetometers being disposed on a plane parallel to a bottom surface of the cryostat;
• a processor processing magnetic field wave forms detected by the magnetometers;
• and
• a display displaying results obtained by the processor,
• wherein the processor estimates a position of the heart of the foetus from the magnetic field wave forms assuming one current dipole exists in the heart of the foetus and time variations of the position of the one current dipole projected on an x-y plane which is the bottom surface of the cryostat and time variations of the position of the one current dipole projected on a y-z plane or an x-z plane which is perpendicular to the x-y plane and parallel to a z axis which is parallel to a center axis of the cryostat;
• and
• wherein the time variations of the position of the one current dipole projected on the x-y plane, the time variations of the position of the one current dipole projected on the y-z plane or the x-z plane and a straight line representing the bottom surface of the cryostat with which the abdomen surface of the pregnant woman is closely contacted are displayed on the display, and a movement, in the x-y plane and the y-z plane or the x-z plane, of the heart of the fetus in the pregnant woman is displayed on the display.