APPARATUS AND METHODS FOR DETECTING INCREASE IN INTRACRANIAL PRESSURE

• US 20150359448A1
• Filed: 06/11/2015
• Published: 12/17/2015
• Est. Priority Date: 06/11/2014
• Status: Active Grant

• Current Assignee: Nihon Kohden Corporation
• Original Assignee: Nihon Kohden Corporation
• Inventors: Beach, Kirk Watson
• Granted Patent: US 10,064,563 B2
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: A61B 5/0082 adapted for particular medical purposes
• CPC Class Codes: A61B 5/0205 Simultaneously evaluating both cardiovascular conditions and different types of body conditions, e.g. heart and respiratory condition
• CPC Class Codes: A61B 5/024 Detecting, measuring or recording pulse rate or heart rate A61B5/0205, A61B5/021 take precedence
• CPC Class Codes: A61B 5/031 Intracranial pressure
• CPC Class Codes: A61B 5/053 Measuring electrical impedance or conductance of a portion of the body
• CPC Class Codes: A61B 5/08 Detecting, measuring or recording devices for evaluating the respiratory organs A61B5/0205 takes precedence
• CPC Class Codes: A61B 5/11 Measuring movement of the entire body or parts thereof, e.g. head or hand tremor, mobility of a limb for measuring pulse A61B5/02 ;A61B5/1038 takes precedence; motion detection to correct for motion artifacts in physiological signals A61B5/721
• CPC Class Codes: A61B 5/4064 Evaluating the brain A61B5/031, A61B5/369, A61B5/14553 take precedence
• CPC Class Codes: A61B 8/0808 for diagnosis of the brain
• CPC Class Codes: A61B 8/15 Transmission-tomography
• CPC Class Codes: A61B 8/4477 using several separate ultrasound transducers or probes
• CPC Class Codes: A61B 8/488 involving Doppler signals
• CPC Class Codes: A61B 8/5207 involving processing of raw data to produce diagnostic data, e.g. for generating an image reconstruction G06T11/00
• CPC Class Codes: A61B 8/5223 for extracting a diagnostic or physiological parameter from medical diagnostic data for algorithms to analyse biomedical images G06T7/0012

Abstract

The disclosed subject matter related to methods and apparatus for determining brain swelling in a patient as well as predicting an increase in intracranial pressure in the patient. The apparatus can include a transducer such as an ultrasound transducer communicatively connected to a controller via wires or via wireless communications device(s). A monitor and/or alarm device can be provided to notify a practitioner when the controller has determined brain swelling is occurring and/or when an imminent increase in intracranial pressure is likely to occur.

Claims

1. A method of predicting intracranial pressure increase in a patient, comprising:

placing a transducer adjacent a skull;

determining at least one of location and motion of a first tissue portion based on information received by the transducer; and

predicting an increase in intracranial pressure based on at least one of the location and the motion of the first tissue portion.

2. The method of claim 1, wherein

determining includes determining at least one of location and motion of the first tissue portion relative to at least one of location and motion of a second tissue portion based on information received by the transducer;

and

predicting includes predicting an increase in intracranial pressure based on at least one of the location and the motion of the first tissue portion relative to the at least one of the location and the motion of the second tissue portion.

3. The method of claim 1, wherein

placing a transducer adjacent the skull includes securing the transducer using one of an elastic band and an adhesive such that long term monitoring by the transducer can be achieved.

4. The method of claim 1, further comprising:

evaluating a cerebral arteriolar pulsation function of brain perfusion of the patient; and

evaluating a respiratory function of brain perfusion of the patient.

5. The method of claim 1, further comprising:

obtaining cerebral circulatory information related to a respiratory cycle of the patient;

obtaining cerebral arteriolar pulsation information related to a cardiac cycle of the patient'"'"'s heart;

obtaining information about the Central Venous Pressure (CVP) referenced to a right atrium of the patient'"'"'s heart, and

obtaining the elevation difference between the brain and the right atrium of the patient'"'"'s heart, and

using the respiratory information and the pulsation information with the CVP and elevation to calculate at least one of location and motion of the first tissue portion.

6. The method of claim 1, further comprising:

obtaining respiratory information related to a respiratory function of the patient;

obtaining pulsation information related to a cardiac function of the patient;

obtaining information about skull motion including translational and rotational acceleration; and

using the respiratory information and the pulsation information to determine whether respiratory, pulsatile or accelerational tissue movement is restricted due to brain swelling or ventricular expansion.

7. The method of claim 6, wherein

the predicting of an increase in intracranial pressure is based on information that motion of the first tissue portion has decreased.

8. The method of claim 1, wherein

the predicting of an increase in intracranial pressure is based on information that motion of the first tissue portion has decreased.

9. The method of claim 1, further comprising:

placing an accelerometer on at least one of a sternum and a head of the patient, and

determining the relative elevation between a right atrium of the patient'"'"'s heart and the patient'"'"'s brain.

10. The method of claim 9, further comprising:

using information received from the accelerometer to determine whether movement of the first tissue is due to brain swelling or due to movement or elevation of at least one of the head and the torso of the patient.

11. The method of claim 2, wherein the first tissue portion is a first brain tissue portion, and the second tissue portion is a second brain tissue portion different from the first brain tissue portion.

12. The method of claim 1, wherein the transducer is an ultrasound scanhead transducer.

13. The method of claim 1, wherein the transducer is one of an optical and an impedance transducer.

14. The method of claim 1, further comprising:

obtaining arteriolar pulsation information related to a cardiac function of the patient;

measuring cerebral perfusion pressure; and

when differential pulsation stops, and the perfusion pressure drops below positive, treating the patient for intracranial pressure increase.

15. The method of claim 2, wherein predicting includes

predicting an increase in the volume of an intracranial structure or intracranial pressure based on information that motion of the first tissue portion relative to the second tissue portion has decreased.

16. The method of claim 1, wherein predicting includes

predicting an increase in the volume of an intracranial structure or intracranial pressure based on information that motion of the first tissue portion has decreased.

17. An apparatus for predicting intracranial pressure increase in a patient, comprising:

a transducer configured for attachment to the patient'"'"'s head;

at least one of a monitor and an alarm device; and

a controller communicatively connected to both the transducer and the at least one of the monitor and the alarm device, the controller configured to receive information from the transducer related to at least one of a location and a motion of a first tissue portion relative to at least one of a location and a motion of a second tissue portion,

the controller further configured to predict an increase in the volume of an intracranial structure of the patient or intracranial pressure of the patient based on information that motion of the first tissue portion relative to the second tissue portion has decreased, and the controller configured to output a signal to the at least one of the monitor and the alarm device if the controller predicts the increase in the volume of an intracranial structure or intracranial pressure.

18. The method of claim 17, wherein the transducer is an ultrasound scanhead transducer.

19. The apparatus of claim 17, further comprising:

at least one accelerometer communicatively connected to the controller, the at least one accelerometer configured for attachment to at least one of the chest and the head of the patient.

20. The apparatus of claim 19, wherein the controller is configured to receive information from the at least one accelerometer and to use the information to determine whether motion of the first tissue is due to brain swelling or due to movement of at least one of the chest and head of the patient.

21. The apparatus of claim 17, further comprising:

a respiratory sensor communicatively connected to the controller and configured to determine a respiratory function of the patient.

22. The apparatus of claim 17, further comprising:

a cardiac sensor communicatively connected to the controller and configured to determine a cardiac function of the patient.

23. The apparatus of claim 17, further comprising:

a respiratory sensor communicatively connected to the controller and configured to obtain respiratory information related to a respiratory function of the patient; and

a cardiac sensor communicatively connected to the controller and configured to obtain cardiac information related to a cardiac function of the patient, wherein

the controller is configured to use the respiratory information and the cardiac information to calculate at least one of location and motion of the first tissue portion.

24. The apparatus of claim 17, wherein the first tissue portion is a first brain tissue portion, and the second tissue portion is a second brain tissue portion different from the first brain tissue portion.

25. A method of determining at least one of normal and abnormal changes in intracranial blood and fluid volumes in a patient, comprising:

providing a transducer configured to be attached to the patient'"'"'s head, a controller configured to receive signals from the transducer, and at least one of a monitor and an alarm device;

obtaining a velocity of an intracranial tissue point using the signal from the transducer and via a calculating protocol performed by the controller;

comparing the velocity of the intracranial tissue point to one of a data set of known velocities for the intracranial tissue point and a velocity of another intracranial tissue point stored in the controller;

identifying at least one of normal and abnormal changes in intracranial blood and fluid volumes based on comparing the velocity of the intracranial tissue point.

26. The method of claim 25 where at least one component of the velocity of the intracranial tissue point changes in a repetitive manner and is measured as a frequency, the method further comprising:

adjusting data related to the velocity of the intracranial tissue point if the frequency is equal to a heart rate of the patient or a harmonic of the heart rate.

27. The method of claim 26 further comprising:

indicating changes in perfusion if the frequency is between 0.5 and 5 Hz.

28. The method of claim 25 where one component of the velocity of the intracranial tissue point changes in a repetitive manner and is measured as a frequency, and

adjusting data related to the velocity of the intracranial tissue point if the frequency is equal to a respiratory rate of the patient.

29. The method of claim 25 where one component of the velocity of the intracranial tissue point changes in a repetitive manner and is measured as a frequency,

indicating one of changes in venular perfusion and venular collapse due to increased intracranial pressure if the frequency is between 0.2 and 0.5 Hz.

indicating possible expulsions of cerebral spinal fluid from the patient'"'"'s brain ventricles through the patient'"'"'s foramen magnum and into the patient'"'"'s spinal column if the frequency is below 0.1 Hz.