Intracranial pressure estimating method and intracranial pressure estimating device

Patent metadata

Field	Value
Publication number	US-11278212-B2
Application number	US-201716309424-A
Country	US
Kind code	B2
Filing date	Jun 12, 2017
Priority date	Jun 17, 2016
Publication date	Mar 22, 2022
Grant date	Mar 22, 2022

Abstract

An intracranial pressure estimating method includes: an acquisition step (S10) of acquiring time-series data on external ear canal pressure pulse waves of a subject; an analysis step (S12) of analyzing external ear canal pressure pulse wave data obtained by digitalizing the time-series data on the external ear canal pressure pulse waves, to calculate a first formant frequency of the external ear canal pressure pulse wave data; a correction step (S13) of correcting the calculated first formant frequency based on personal information on the subject to calculate a corrected value; and an estimation step (S14) of calculating an estimated value of an intracranial pressure based on the calculated corrected value.

First claim

The invention claimed is:

1. An intracranial pressure estimating method for estimating an intracranial pressure from time-series data on external ear canal pressure pulse waves, the method comprising:
an acquisition step of acquiring time-series data on external ear canal pressure pulse waves of a subject from a microphone or a pressure sensor disposed within the subject's ear;
an analysis step of analyzing external ear canal pressure pulse wave data obtained by digitalizing the time-series data on the external ear canal pressure pulse waves and calculating a first formant frequency of the external ear canal pressure pulse wave data by performing linear predictive analysis on the digitalized time-series data;
a correction step of correcting the first formant frequency based on age information and gender information for the subject to calculate a corrected value; and
an estimation step of calculating an estimated value of an intracranial pressure based on the corrected value.

2. The intracranial pressure estimating method according to claim 1 , wherein the analysis step includes analyzing data obtained by subjecting the external ear canal pressure pulse wave data to high-pass filter processing to calculate the first formant frequency.

3. The intracranial pressure estimating method according to claim 1 , wherein the estimation step includes calculating an estimated value PICP of the intracranial pressure based on the following equation:
PICP= A ·ln( Xf 1)+ B

where A and B are constants, and Xf1 is the corrected value.

4. The intracranial pressure estimating method according to claim 3 , wherein the correction step includes calculating the corrected value Xf1 based on the following equation:
Xf 1= f 1+β1·ln( K /Age)+β2· FM

where f1 is the first formant frequency, β1, K, and β2 are constants, Age is the age information of the subject, and FM is the gender information of the subject (0 for male and 1 for female).

5. The intracranial pressure estimating method according to claim 1 , further comprising a display step of displaying the estimated value of the intracranial pressure on a display.

6. An intracranial pressure estimating device comprising:
an external ear canal pressure pulse wave sensor that detects external ear canal pressure pulse waves of a subject, the sensor being configured to be disposed within the subject's ear; and
an arithmetic unit that estimates an intracranial pressure from time-series data on the external ear canal pressure pulse waves,
wherein the arithmetic unit analyzes external ear canal pressure pulse wave data obtained by digitalizing the time-series data on the external ear canal pressure pulse waves, calculates a first formant frequency of the external ear canal pressure pulse wave data by performing linear predictive analysis on the digitalized time-series data, corrects the first formant frequency based on age information and gender information for the subject to calculate a corrected value, and calculates an estimated value of the intracranial pressure based on the corrected value.

7. The intracranial pressure estimating device according to claim 6 , further comprising a display that displays the estimated value of the intracranial pressure.

8. An intracranial pressure estimating device comprising:
a microphone or a pressure sensor configured to detect external ear canal pressure pulse waves of a subject, the microphone or the pressure sensor being configured to be disposed within the subject's ear; and
a processor programmed to estimate an intracranial pressure from time-series data on the external ear canal pressure pulse waves,
wherein the processor analyzes external ear canal pressure pulse wave data obtained by digitalizing the time-series data on the external ear canal pressure pulse waves, calculates a first formant frequency of the external ear canal pressure pulse wave data by performing linear predictive analysis on the digitalized time-series data, corrects the first formant frequency based on age information and gender information for the subject to calculate a corrected value, and calculates an estimated value of the intracranial pressure based on the corrected value.

9. The intracranial pressure estimating device according to claim 8 , further comprising a display that displays the estimated value of the intracranial pressure.

Assignees

• Ichikawa Electric Co Ltd
• Univ Shinshu

Inventors

• Koike Norio
• Yasumoto Satoshi
• Nakano Jun
• Sai Yukio
• Furihata Kenji
• Goto Tetsuya
• Hongo Kazuhiro

Classifications

• A61B5/036

  by means introduced into body tracts (A61B5/032 and A61B5/035 take precedence) · CPC title

• A61B5/7235

  Details of waveform analysis (detecting specific parameters of the electrocardiograph cycle A61B5/349) · CPC title

• A61B5/024

  Measuring pulse rate or heart rate · CPC title

• A61B5/031 Primary

  Intracranial pressure · CPC title

• A61B5/6817

  Ear canal · CPC title