US 5,309,095 A · Compact magnetometer probe and an array of them covering the whole human skull for measurement of magnetic fields arising from the activity of the brain

Abstract

A sensor element of thin film components and fiber glass, and a support structure of fiber glass; when sensor elements are attached to the support structure, a sensor system for magnetoencephalographic measurements is formed. A substrate containing a planar signal coil and a SQUID is attached on a circuit board of fiber glass using a spring cut on the edge of a body plate. On the sensor element, is a small but mechanically stable connector or several such connectors (5); when the sensor element is plugged in receptacles (6) on the support structure (7), the element settles in a well defined orientation. Support structure (7) is made of a fiber glass shell following the shape of the bottom (10) dewar vessel, adapted to the shape of the head. The receptacles (6) are attached to the glass fiber shell by springs (9) made of thin fiber glass plate such that an array covering the whole skull as evenly as possible is formed when the sensor elements are plugged to the receptacles. The spring is cut to enable rotation only around an arbitrary axis in the plane of the spring and a translation only in a direction perpendicular to the plane of the spring. When this support structure is inserted in the dewar, individual sensor elements lean against the dewar bottom (10) by aid of three feet (11), pressed by springs (9), settling perpendicularly to the normal of the dewar bottom passing through the center of the sensor element.

Claims23

Dependent claims

A device for sensing time and space dependent magnetic fields arising from neural activity in the human brain, said device being suitable for use in a vessel containing a cryogenic liquid and having a curved wall portion configured to embrace the human cranium, said device comprising;

a plurality of SQUID magnetic field sensing means for sensing the magnetic fields, said plurality of SQUID means being coupled to a support structure positionable within said vessel (7) for locating said SQUID means at selected locations on said vessel wall portion, each of said SQUID means having a generally planar base element (2) and foot means (11) extending from said base element for positioning said SQUID means on said vessel wall portion (10) in a predetermined orientation with respect thereto.

Apparatus for sensing time and space dependent magnetic fields arising from neural activity in the human brain, said apparatus comprising:

a vessel containing a cryogenic fluid and having a curved wall portion configured to embrace the human cranium, said curved wall portion (10) of said vessel being defined by portions of generally hemispherical surfaces of two, non-concentric, intersecting spheres of different radii (19, 20);
the surface portion (31) of a cone (21) tangent to both said spheres, the surface portion included from said cone being the portion between the circles of tangency (28, 29) of said generally hemispherical portions;
and a surface portion (23) of a right cylinder tangent to both the spheres, the included portion of the cylinder being a portion that extends from the tangential line (30) of the cylinder and spheres by an amount which covers the occipital section of the cortex of the brain but which leaves the eyes uncovered when said wall portion embraces the cranium;
a plurality of SQUID magnetic field sensing means for sensing the magnetic fields, each of said SQUID means having a generally planar base element (2) and foot means (11) extending from said base element for positioning said SQUID means on said vessel wall portion;
and
a support structure (7) formed to correspond with, and lie proximate to, said curved wall portion of said vessel;
said SQUID means being mounted at spaced locations on said support structure such that the planar base element of each of said SQUID means lies generally in a condition of tangency with the curved wall portion of said vessel proximate to each of said SQUID means.

4 more elements

Dependencies are inferred from the claim text.

Compact magnetometer probe and an array of them covering the whole human skull for measurement of magnetic fields arising from the activity of the brain

Life of this patent

Compact magnetometer probe and an array of them covering the whole human skull for measurement of magnetic fields arising from the activity of the brain

Life of this patent

Abstract

Claims23