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CA-3255410-C - COIL POSITIONING SYSTEM FOR NONINVASIVE BRAIN SENSOR

CA3255410CCA 3255410 CCA3255410 CCA 3255410CCA-3255410-C

Abstract

A helmet-like medical diagnostic apparatus that is fixed or worn has motorized gimbals that automatically swivel to positions around a patient's head. An end effector extends radially from the gimbals toward the head to place a coil or other directional sensor snugly against the scalp. A coil sensor can be part of a sensitive circuit to measure eddy currents within the brain. Accelerometers, or other tilt-measuring gauges, are compared between those on the sensor and those on the apparatus's base to determine the precise 3D orientation of the sensor when resting against the head. The orientation can compensate coil measurements, find an exact spot again, or map opposing sides of the patient's cranium, even with a fidgeting unconscious patient. The head can be scanned in its entirety, or a spot scan may be prompted from other diagnostic data.

Inventors

  • Shane S. Shahrestani
  • Alexander M. Ballatori
  • Brian L. Nguyen
  • Robert LUKE
  • John M. Vernon
  • Lance G. Hussey
  • Cary R. Chow
  • Ravi K. Sawhney

Assignees

  • StrokeDx, Inc.
  • StrokeDx, Inc.

Dates

Publication Date
20260505
Application Date
20240118
Priority Date
20230301

Claims (20)

  1. 1 CLAIMS: 2 1. An inductive sensor apparatus for brain diagnostics, the apparatus comprising: 3 a headrest plinth configured to hold a head of a subject, the subject’s head having a 4 notional spherical center point; 5 a first tilt gauge rigidly attached to the plinth; 6 a gimbal armature pivotably attached to the plinth and configured to pivot a mounting 7 point on the gimbal armature to latitudes and longitudes around the center point; 8 a radial extender mounted to the mounting point of the gimbal armature, the radial 9 extender configured to extend an end effector inward with respect to the center point; 10 a coil sensor affixed to the end effector; 11 a second tilt gauge affixed to the coil sensor; 12 a resistive, inductive, and capacitive (RLC) circuit electrically connected with the coil 13 sensor; and 14 a frequency counter electrically connected with the RLC circuit. 1
  2. 2. The apparatus according to claim 1 further comprising: 2 a memory; and 3 a computer processor operatively coupled with a machine-readable non-transitory 4 medium comprising instructions that, when executed by the computer processor, cause the 5 processor to perform operations comprising: 6 comparing tilt angles from the first tilt gauge and the second tilt gauge to 7 determine a relative orientation of the coil sensor; and 8 calculating a three-dimensional (3D) anatomical location of a measured value 9 from the coil sensor based on the orientation. 1
  3. 3. The apparatus according to claim 2 wherein the operations further comprise: 2 adjusting the measured value from the coil sensor based on the orientation. 1
  4. 4. The apparatus according to claim 3 wherein the adjusting includes 2 compensating for movement of the subject’s head between measurements at the same 3 anatomical location. 1
  5. 5. The apparatus according to claim 2 or 3 wherein the operations further 2 comprise: 21 commanding the gimbal armature to rotate to a specified 3 latitude and a specified 4 longitude; 5 directing the radial extender to extend the coil sensor at the specified latitude and the 6 specified longitude; 7 generating the measured value based on output created by the coil sensor; and 8 associating the measured value with the 3D anatomical location to create an 9 anatomically located measurement. 1
  6. 6. The apparatus according to claim 5 wherein the anatomically located 2 measurement is a left anatomically located measurement from a left hemisphere of the head, 3 the operations further comprising: 4 making a right anatomically located measurement on a right hemisphere of the head; 5 comparing the left and right left anatomically located measurements from the left and 6 right hemispheres of the head; and 7 outputting an indication based on the comparing. 1
  7. 7. The apparatus according to claim 5 wherein the anatomically located 2 measurement is an earlier anatomically located measurement from an earlier time, the 3 operations further comprising: 4 making a later anatomically located measurement at a later time; 5 comparing the earlier and later anatomically located measurements; and 6 outputting an indication based on the comparing. 1
  8. 8. The apparatus according to claim 5 wherein the operations further comprise: 2 accessing computed tomography (CT) data or magnetic resonance imaging (MRI) 3 data from a scan of the head; and 4 determining an anatomical coordinate in the head based on the CT or MRI data, 5 wherein the specified latitude and specified longitude are based on the anatomical 6 coordinate. 1
  9. 9. The apparatus according to claim 5 wherein the operations further comprise: 2 creating a set of anatomically located measurements that includes the anatomically 3 located measurement; and 4 generating a physical topography of the head from the measurements or rendering an 5 image based on the measurements. 22
  10. 10. The apparatus according to any one of claims 1 2-9 wherein the operations 2 further comprise: 3 generating the measured value based on an output from the frequency counter 4 when the coil sensor is at a cranial location on the head. 1
  11. 11. The apparatus according to claim 10 wherein the coil sensor is a first coil 2 sensor, the RLC circuit is a first RLC circuit, and the frequency counter is a first frequency 3 counter, the apparatus further comprising: 4 a second coil sensor having a larger or smaller diameter than the first coil sensor, the 5 first and second coil sensors sharing a housing; 6 a second RLC circuit electrically connected with the second coil sensor; and 7 a second frequency counter electrically connected with the second RLC circuit. 1
  12. 12. The apparatus according to any one of claims 1-11 wherein the first and 2 second tilt gauges include three-dimensional (3D) accelerometers. 1
  13. 13. The apparatus according to any one of claims 1-12 wherein the radial extender 2 includes a scissoring device or a telescoping mechanism. 1
  14. 14. The apparatus according to any one of claims 1-13 further comprising: 2 a motor; 3 a pulley wheel on the mounting point; and 4 a pulley cable extending between the motor and the radial extender through the pulley 5 wheel, 6 the motor located remotely from the mounting point in order to avoid electromagnetic 7 interference with the coil sensor. 1
  15. 15. A method for anatomically locating measurements in a subject’s brain, the 2 method comprising: 23 providing a headrest plinth configured to hold a head of 3 a subject, the subject’s head 4 having a notional spherical center point, a first tilt gauge rigidly attached to the plinth, a 5 gimbal armature pivotably attached to the plinth and configured to pivot a mounting point on 6 the gimbal armature to latitudes and longitudes around the center point, a radial extender 7 mounted to the mounting point of the gimbal armature, the radial extender configured to 8 extend an end effector inward with respect to the center point, a coil sensor affixed to the end 9 effector, a second tilt gauge affixed to the coil sensor, a resistive, inductive, and capacitive 10 (RLC) circuit electrically connected with the coil sensor, and a frequency counter electrically 11 connected with the RLC circuit; 12 measuring tilt angles using the first tilt gauge and the second tilt gauge; 13 measuring a value using the coil sensor; and 14 using a computer processor to: 15 compare the measured tilt angles from the first tilt gauge and the second tilt 16 gauge to determine a relative orientation of the coil sensor; and 17 calculate a three-dimensional (3D) anatomical location of a measured value 18 from the coil sensor based on the orientation. 1
  16. 16. The method according to claim 15 further comprising: 2 adjusting the measured value from the coil sensor based on the orientation. 1
  17. 17. The method according to claim 15 or claim 16 further comprising: 2 commanding the gimbal armature to a specified latitude and a specified longitude; 3 directing the radial extender to extend the coil sensor at the specified latitude and the 4 specified longitude; 5 generating the measured value based on output created by the coil sensor; and 6 associating the measured value with the 3D anatomical location to create an 7 anatomically located measurement. 1
  18. 18. The method according to claim 17 wherein the anatomically located 2 measurement is a left anatomically located measurement from a left hemisphere of the head, 3 the method further comprising: 4 making a right anatomically located measurement on a right hemisphere of the head; 5 comparing the measurements left and right anatomically located from the left and 6 right hemispheres of the head; and 7 outputting an indication based on the comparing. 24
  19. 19. The method according to claim 17 wherein 1 the anatomically located 2 measurement is an earlier anatomically located measurement from an earlier time, the method 3 further comprising: 4 making a later anatomically located measurement at a later time; 5 comparing the earlier and later anatomically located measurements; and 6 outputting an indication based on the comparing. 1
  20. 20. A method of manufacturing an inductive sensor apparatus for brain 2 diagnostics, the method comprising: 3 providing a headrest plinth configured to hold a head of a subject, the subject’s head 4 having a notional spherical center point; 5 rigidly attaching a first tilt gauge to the plinth; 6 pivotably attaching a gimbal armature to the plinth so that the gimbal armature is 7 configured to pivot a mounting point on the gimbal armature to latitudes and longitudes 8 around the center point; 9 mounting a radial extender to the mounting point of the gimbal armature so as to 10 configure the radial extender to extend an end effector inward with respect to the center 11 point; 12 affixing a coil sensor to the end effector; 13 affixing a second tilt gauge to the coil sensor; 14 electrically connecting a resistive, inductive, and capacitive (RLC) circuit with the 15 coil sensor; and 16 electrically connecting a frequency counter with the RLC circuit.

Description

1 COIL POSITIONING SYSTEM FOR NONINVASIVE BRAIN SENSOR CROSS-REFERENCES TO RELATED APPLICATIONS [0001] This application claims the benefit of U.S. Provisional Application No. 63/449,238, filed March 1, 2023, and U.S. Provisional Application No. 63/588,278, filed October 5, 2023. STATEMENT AS TO RIGHTS TO INVENTIONS MADE UNDER FEDERALLY SPONSORED RESEARCH AND DEVELOPMENT [0002] NOT APPLICABLE BACKGROUND [0003] 1. Field of the Art [0004] Embodiments of the present invention generally relate to arrangements of detecting and measuring, for diagnostic purposes, electromagnetic anomalies within a subject’s head with specially adapted means to be attached thereto, including means for indicating the position of a sensor on the body. Specifically, they relate to robotically positioning and repositioning a coil or other directional sensor against the subject’s scalp, detecting the sensor’s precise anatomical position and orientation with respect to the head, and outputting calibrated measurements. [0005] 2. Description of the Related Art [0006] Diagnosing a possible stroke in a patient is frequently difficult because the stroke victim is often unconscious, and there are few, if any, visible indications of what is going on inside the patient’s cranium. Further, a treating physician is under time pressure to proceed with a course of treatment. Each minute that passes untreated—or with the wrong treatment—can result in greater and greater brain damage, often permanent. [0007] The wrong treatment may be fatal. Treatment for an ischemic stroke involves administering blood thinners. However, if the patient is actually experiencing a hemorrhagic stroke, then the blood thinners may worsen the problem by letting internal bleeding within the brain continue unabated by the blood's natural coagulation properties. 5 [0008] Currently, computed tomography (CT) and magnetic resonance imaging (MRI) are the two gold standards for diagnosing and monitoring brain health for stroke patients. When available, they help immensely by providing a treating physician with a view inside the patient's brain. And they are employed repeatedly on the patient so as to track progress, or lack thereof. 10 [0009] However, these devices are large, expensive, often require specialized staff, and are mostly restricted to larger hospital systems. CT scans give a non-negligible radiation dose, which adds to the patient's cancer risk. Neither can be used continuously on a patient bedside. [0010] There is a need in the art for portable and less expensive systems that can detect a 15 fluidic anomaly within a patient's head and monitor it over time, among other things. BRIEF SUMMARY [0011] A medical diagnostic device for a patient's head includes a temporarily or permanently fixed headrest base with a gimbal assembly that can pivot to latitudes and 20 longitudes over the patient's sphere-like skull. An end effector mounted on the gimbal assembly can robotically extend inward from the gimbal to place a coil or other directional sensor against the patient's scalp. The sensor may cant slightly when pressing against the scalp in order to conform to the scalp's local topology. A tilt sensor affixed to the coil sensor measures this cant with respect to the base, and the precise orientation and position of the coil 25 sensor with respect to the headrest are then known for the coil's magneto-electrical measurement. [0012] Precisely located measurements, such as eddy current measurements, can be compared over time or with respect to the left and right hemispheres of the brain. Computed tomography (CT) data or magnetic resonance imaging (MRI) data can be uploaded into the 30 device to spot check [0013] Some embodiments of the present invention are related to an inductive sensor apparatus for brain diagnostics, the apparatus including a headrest plinth configured to hold a 2 head of a subject, the subject's head having a notional spherical center point, a first tilt gauge rigidly attached to the plinth, a gimbal armature pivotably attached to the plinth and configured to pivot a mounting point on the gimbal armature to latitudes and longitudes around the center point, a radial extender mounted to the mounting point of the gimbal 5 armature, the radial extender configured to extend an end effector inward along a radial line with respect to the center point, a coil sensor affixed to the end effector, and a second tilt gauge affixed to the sensor. [0014] The apparatus can further include a memory and a computer processor operatively coupled with the machine-readable non-transitory medium embodying information indicative 10 of instructions for causing the computer processor to perform operations comprising comparing tilt angles from the first tilt gauge and the second tilt gauge to determine a relative orientation of the coil sensor, and calculating a three-dimensional (3D) anatomical location of a measured value from the coil sensor based on the orientation. [0015] The operat