Biomagnetic Technologies, Inc.

Fisher Scientific Company

Laurence Warden

Keith Allen Esser

Scott W Riley

D Scott Buchanan

Richard T Johnson

K Randy Brimhall

David H Burkett

Frank W Vanesky

David E Kaplan

Johathan R Ferris

A biomagnetometer includes a dewar vessel having a helmet-shaped recess at the lower end of its body. The recess is angled at about 45 degrees to the dewar body axis of the dewar vessel. Biomagnetic sensors are positioned within the interior of the dewar vessel body around the periphery of the recess. The angled recess permits the biomagnetometer to be used with subjects whose heads are inclined from 0 to 90 degrees to the horizontal by pivoting the dewar vessel over an angle of from -45 degrees to +45 degrees to the vertical, without spilling the cryogenic fluid within the dewar or causing excessive evaporation of the cryogenic fluid.

Biomagnetometer with whole head coverage of a seated reclined subject

A thermally conductive feedthrough has a conductive member extending through a fiber-reinforced plastic plate. The feedthrough is sealed against leakage from one side of the plate to the other by placing the plate in local compression to seal it against the plate and/or by using small individual conductive members that minimize the effects of thermal expansion differences. The feedthrough can be used between vacuum and cryogenic liquids.

Solid conductor thermal feedthrough

A biomagnetometer includes a magnetic field sensor including a magnetic field pickup coil and a detector of small electrical currents flowing within the pickup coil. A vacuum-tight enclosure surrounds the sensor. The enclosure has a concavely upwardly curved first wall, with the magnetic field pickup coil located adjacent to the first wall. A vented reservoir of liquefied gas is located within the enclosure, and a solid thermal conductor extends from the sensor. There is a vacuum-tight thermal feedthrough by which the solid thermal conductor passes between the interior and the exterior of the enclosure. Electronic circuitry for filtering and amplifying the signals of the detector is also provided. Such a biomagnetometer is placed below the body of a reclining subject, and a second portion of the biomagnetometer can be placed above the body. In one form, the enclosures are shaped to form a cavity that receives the head of the subject therein, to achieve full head coverage of the pickup coils in the biomagnetometer.

Biomagnetometer with sealed vacuum enclosure and solid conduction cooling

Biomagnetometer with whole head coverage of a seated or reclined subject

A biomagnetometer comprises an array of biomagnetic sensors, the array comprising a first plurality of magnetic field pickup coils, and a second plurality of detectors, each of which receives a pickup coil output from a pickup coil. There is a third plurality of signal processors, each of which receives an output from a detector, the third plurality of signal processors being fewer in number than the first plurality of pickup coils. The biomagnetometer further includes a selector that selects a subset of pickup coils, equal in number to the third plurality of signal processors, from the first plurality of pickup coils for signal processing by the signal processors. This biomagnetometer permits the placement of a very large array of relatively inexpensive pickup coils adjacent to a subject, and then processing information from subsets of that large array selected to optimize the gathering of data, while maintaining the cost of the signal processing electronics at a more economical level.

Biomagnetometer with selectable pickup coil array

A dewar includes an inner dewar and a dewar thermal shield. The dewar thermal shield has a thermal shield body formed of a layer of radiative insulation, an inner layer of fiberglass cloth overlying the layer of radiative insulation, a metallic screen overlying the inner layer, and an outer layer of fiberglass cloth overlying the metallic screen. The dewar thermal shield also has a thermal shield tail cap attached to the thermal shield body. The tail cap is formed of a layer of radiative insulation, a layer of fiberglass cloth overlying the layer of radiative insulation, a layer of thermal foil overlying the layer of fiberglass cloth, the thermal foil being formed of thermal conductors embedded in a film adhesive matrix with the thermal conductors extending to the body, and a top layer of fiberglass cloth overlying the layer of thermal foil.

Cryogenic dewar and method of fabrication

A thermal foil material is made of a layer of B-staged curable epoxy film adhesive and a plurality of substantially parallel insulated copper wires embedded in the epoxy layer. The copper wires are arranged in a side-by-side fashion in at least one layer within the epoxy. Such a thermal foil material is prepared by furnishing a first sheet of a B-staged film adhesive material, preferably wrapped over a mandrel, and placing a layer of metallic elements onto the first sheet with the metallic elements arranged in a side-by-side fashion. A second sheet of a B-staged film adhesive material is placed over the layer of metallic elements and the first sheet. The stack is heated and pressure is applied perpendicular to the first and second sheets to cause the B-staged film adhesive mate rial to flow into the interstices between the metallic elements. This material may be used immediately or stored to prevent further curing of the epoxy until it is used.

Method of preparing film adhesive thermal foil

An apparatus for making bioelectromagnetic measurements of the human body includes an apparatus for measuring the bioelectromagnetic reaction of a living body to a tactile stimulation and a tactile stimulator that controllably applies a tactile stimulation to the body without creating a magnetic or electrical field that is detected directly by the apparatus for measuring the bioelectromagnetic reaction. The tactile stimulator includes a pressure chamber closed on one side by a movable body such as a piston or flexible membrane, a conduit that transmits pneumatic pressure to the pressure chamber, and apparatus for applying pneumatic pressure to the conduit. The measuring apparatus, such as a biomagnetometer, may be located within a shielded room, and in this case the pressure chamber and movable body are preferably located within the shielded room, the apparatus for applying pneumatic pressure is located outside the room, and the conduit passes from the exterior to the interior of the room.

Nonmagnetic tactile stimulator and biomagnetometer utilizing the

A linear peristaltic pump equipped with a pressure relief mechanism for pumping I.V. fluids to a patient comprises a platen for supporting the tube, and a plurality of fingers which sequentially urge against the tube resting against the platen for creating a moving zone of occlusion. Cam lobes are formed to lift a penultimate and ultimate finger off of the tube at a rate faster than the other fingers to prevent pressure increases inside the tube which would otherwise be caused by other fingers urging against the tube. Additionally, the ultimate finger may be shortened with respect to the other fingers to reduce the total occlusion time of the ultimate finger to provide a more linearized flow of fluid to the patient.

Growing community of inventors

San Diego, CA, United States of America

Laurence Warden