CN111820908A - Probe detector for otoacoustic abnormal cavity and detection method thereof - Google Patents

Abstract

The invention provides a probe detector of an otoacoustic abnormal cavity, which is characterized in that an electroacoustic ring energy device and an acoustoelectric transducer for receiving sound are arranged in a probe shell, and a cavity to be detected is connected with the shell through a sound transmitting and receiving pipeline; the shell is provided with a pulse stimulation sound system. The detection method comprises the steps that a probe emits basic stimulus sound, and a pulse stimulus sound system plays short stimulus sound; and storing the generated basic stimulation data into a head file of an otoacoustic detection project by using simulation software, so as to realize the acquisition of a sample, the processing of the sample data, the statistics of stability indexes of transmitted waves and received waves, and the judgment of a probe index of a cavity to be detected. The invention uses digital signal processing technology and machine learning method to realize dynamic automatic calibration of earphone probe, so as to achieve the purpose of distinguishing air and abnormal coupling cavity; the probe detection in air and metal coupling cavity (0.2cc to 0.7cc) and the detection of human ear canal and the calibration of the ear sound probe microphone in a rough type are automatically distinguished by using a program.

Description

Probe detector for otoacoustic abnormal cavity and detection method thereof

Technical Field

The invention relates to a medical hearing detection system, in particular to a probe detector of an otoacoustic abnormal cavity and a detection method thereof.

Background

Otoacoustic emission is a type of audio energy produced in the cochlea, released into the external auditory canal via conduction through the ossicular chain and the tympanic membrane (Kemp, 1986). The sound intensity of the otoacoustic emission signal is weak and does not cause human auditory consciousness, and a high-sensitivity microphone placed in the external auditory canal can record the sound in the auditory canal. Otoacoustic emission detection is an objective hearing detection method starting from infants, and generally detects weak acoustic energy by using a probe, a transceiver and the like after a weak magnetic pole signal is given to a cochlea, so that the aim of hearing detection is fulfilled.

At present, domestic infant otoacoustic screening equipment has few products with independent intellectual property rights, and most of the products in the market at present are foreign product otoacoustic hearing screening equipment. The precision of foreign products is greatly different in clinical use, but the practical effect of microphone calibration schemes of coupler transfer function or compensation methods of acoustic measurement is obvious when anomaly detection of air and metal coupling cavities is carried out, but in the practical calibration, the processing of products which are single screened and depend on a pressure sensor or an additional external microphone and a sound source is complicated. In the otoacoustic detection process, because the infant otoacoustic signals are very weak and are particularly easily influenced by environmental noise or intra-auricular muscle noise, whether the probe is placed normally and whether the probe is placed in the ear greatly influences the acquisition and analysis of the signals. Most of the existing otoacoustic probe detection technologies are used for calibrating and compensating a microphone and depend on the impedance of a cavity to be detected, and in actual otoacoustic detection application, the impedance of the cavity to be detected is generally difficult to accurately obtain. Moreover, the hardware technology of the equipment is high in cost, the calibration error is large under the condition that the circuit noise control is not good, and the technical realization difficulty is high for simple screening products.

Disclosure of Invention

Aiming at the defects of the existing otoacoustic detection, the invention aims to solve the technical problem of providing a probe detector of an otoacoustic abnormal cavity and a detection method thereof. The probe detection in air and metal coupling cavity (0.2cc to 0.7cc) and the detection of human ear canal and the calibration of the ear sound probe microphone in a rough type are automatically distinguished by using a program.

In order to solve the technical problems, the technical scheme adopted by the invention is as follows: a probe detector of an acoustic anomaly cavity comprises a probe shell, wherein an electroacoustic ring energy device and an acoustoelectric transducer for receiving sound are arranged in the shell, and a cavity to be detected is connected with the shell through a sound transmitting and receiving pipeline; the shell is provided with a pulse stimulation sound system.

The pulse stimulation sound system is a simulation software Matlab2015 system, the simulation software Matlab2015 generates pulse stimulation sound with 100 mu s of short sound (click), the intensity M is stimulation pulses with 83dB, the interval is 25ms, the energy is concentrated at 0.5-6kHz, and the sound construction function is as follows:

wherein the basic stimulation waveform is y (t) sin (2 pi multiplied by 24000t), t is more than or equal to 0 and less than or equal to 100 mus, the time is started from 0, and 602 values are calculated at intervals in total to form a group of stimulation sound waveforms; the strength M assumes a fixed magnitude; and storing the generated basic stimulation data into a head file of the otoacoustic detection project by using simulation software.

The detection method comprises the following steps:

the method includes the steps of placing a probe detector, starting testing, and entering a probe detection procedure;

the probe emits basic stimulating sound;

playing short stimulation sound through a pulse stimulation sound system; storing the generated basic stimulation data into a header file of an otoacoustic detection project by using simulation software to realize the acquisition of a sample;

sample data is processed, and a stimulation parameter is calculated:

receiving reflected sound, calculating noise level, and filtering with Hamming window function

Wherein, alpha is 0.46, N is 602, the function processes the noise which is not needed, fast FFT conversion is carried out in the effective frequency range, the energy response of the measured cavity of the reference frequency segment is respectively calculated, and the frequency points are respectively: the energy values of 1KHZ, 2KHZ, 3KHZ, 4KHZ and 5KHZ are used as characteristic values alpha 1, and the number of wave crests appearing in the waveform of 6ms to 15ms of the time domain part is used as a characteristic value alpha 2;

fifthly, in the process of collecting data and calculating the returned sound energy value, counting stability indexes of the transmitted wave and the received wave;

sixth, according to the characteristic parameters alpha 1 and alpha 2 of the fourth step and whether the stability index meets the following requirements in the fifth step: setting 5 data parameter thresholds in the characteristic parameter alpha 1 according to the requirements of DP test or TE test, and setting DP 65 so as to judge the probe index of the cavity to be tested; if so, emitting stimulation sound to meet normal test conditions, and carrying out normal test; if not, the probe is dynamically adjusted, the steps are switched for two seconds, and the test requirements are met until the characteristic parameters and the stability indexes are met.

The stability index in the step of the detection method is as follows:

stimulus sound stability: the similarity between each transmitted wave and the previous transmitted wave is more than 90%;

stability of received wave: the similarity between the complete waveform received each time and the waveform received last time is more than 80%;

similarity: euclidean distance using two sets of discrete data

The similarity is calculated, wherein N is a group of received wave lengths, and 602, data1 and data2 are respectively the stimulation sound or the received reflected sound data of the two times before and after.

According to the probe detector for the sound abnormal cavity and the detection method thereof, which are designed by the technical scheme, the probe detection emission test sound is short sound, the band-pass filter is designed for the sound signal received by the earphone according to the test environment condition, and after short-time Fourier transform, feature extraction and classification detection are carried out on the signals in different frequency domains. The dynamic automatic calibration of the earphone probe is realized by using a digital signal processing technology and a machine learning method on the basis of not increasing the hardware cost, so that the aim of distinguishing air and an abnormal coupling cavity is fulfilled. The invention utilizes the program to automatically distinguish the detection of the probe in the air and the metal coupling cavity from the detection of the human auditory canal and the calibration of the rough type otoacoustic probe microphone. The hardware technology of the invention has low cost, small calibration error under the condition of poor circuit noise control, and small technical realization difficulty for simple screening products.

Drawings

FIG. 1 is a schematic structural diagram of a probe detector for otoacoustic abnormal cavities according to the present invention;

FIG. 2 is a schematic view of the probe detector of the present invention;

FIG. 3 is a schematic view showing the flow structure of the detection method of the present invention.

Detailed Description

The probe detector for otoacoustic abnormal cavities and the detection method thereof of the present invention are specifically described below with reference to the accompanying drawings.

The probe detector of the sound abnormal cavity, referring to fig. 1 and fig. 2, comprises a probe shell 1, wherein an electroacoustic ring energy device 2 (a micro loudspeaker) and an electroacoustic transducer 3 (a micro microphone) are arranged in the shell 1, and the electroacoustic transducer 3 is used for receiving sound. The cavity 5 to be measured is connected with the shell 1 through the transmitting and receiving sound pipeline 4, and the experimental process of the cavity 5 to be measured takes 0.1-0.7 cc. A pulse stimulation sound system is arranged in the shell 1, so that the probe detects a structure of selecting short sound. The pulse stimulation sound system adopts simulation software Matlab2015, the simulation software Matlab2015 generates pulse stimulation sound with 100 mu s of short sound (click), the intensity M is 83dB of stimulation pulses, the interval is 25ms, the energy is concentrated at 0.5-6kHz, and the sound structure function is as follows:

wherein, the basic stimulation waveform is y (t) sin (2 pi multiplied by 24000t), t is more than or equal to 0 and less than or equal to 100 mus, the time is from 0, and 602 values are calculated at intervals in total to form a group of stimulation sound waveforms; the strength M assumes a fixed magnitude; and storing the generated basic stimulation data into a head file of the otoacoustic detection project by using simulation software. The invention selects the earphone channel to circularly transmit the short sound signal, and after delaying for 1 second, the microphone is started to receive the sound signal.

The detection method of the invention, see fig. 3, comprises the following steps:

(1) placing a probe detector, starting a test, and entering a probe detection program;

(2) the probe emits a basic stimulus sound;

playing short stimulation sound through a pulse stimulation sound system; storing the generated basic stimulation data into a header file of an otoacoustic detection project by using simulation software to realize the acquisition of a sample;

sample data is processed, and a stimulation parameter is calculated:

receiving reflected sound, calculating noise level, and filtering with Hamming window function

Wherein, alpha is 0.46, N is 602, the function processes the noise which is not needed, fast FFT conversion is carried out in the effective frequency range, the energy response of the measured cavity of the reference frequency segment is respectively calculated, and the frequency points are respectively: the energy values of 1KHZ, 2KHZ, 3KHZ, 4KHZ and 5KHZ are used as characteristic values alpha 1, and the number of wave crests appearing in the waveform of 6ms to 15ms of the time domain part is used as a characteristic value alpha 2;

fifthly, in the process of collecting data and calculating the returned sound energy value, counting stability indexes of the transmitted wave and the received wave;

wherein, the stability indexes are as follows:

stimulus sound stability: the similarity between each transmitted wave and the previous transmitted wave is more than 90%;

stability of received wave: the similarity between the complete waveform received each time and the waveform received last time is more than 80%;

similarity of characters: euclidean distance using two sets of discrete data

The similarity is calculated, wherein N is a group of received wave lengths, and 602, data1 and data2 are respectively the stimulation sound or the received reflected sound data of the two times before and after.

Sixth, according to the characteristic parameters alpha 1 and alpha 2 of the fourth step and whether the stability index meets the following requirements in the fifth step: setting 5 data parameter thresholds in the characteristic parameter alpha 1 according to the requirements of DP test or TE test, and setting DP 65 so as to judge the probe index of the cavity to be tested; if so, emitting stimulation sound to meet normal test conditions, and carrying out normal test; if not, the probe is dynamically adjusted, the steps are switched for two seconds, and the test requirements are met until the characteristic parameters and the stability indexes are met.

Claims (4)

1. A probe detector of an otoacoustic abnormal cavity comprises a probe shell, and is characterized in that an electroacoustic ring energy device and an acoustoelectric transducer for receiving sound are arranged in the shell, and a cavity to be detected is connected with the shell through a transmitting and receiving sound pipeline; the shell is provided with a pulse stimulation sound system.

2. The probe apparatus of claim 1, wherein the pulsed stimulus sound system is a Matlab2015 simulation software system, the Matlab2015 simulation software system generates 100 μ s short-sound (click) pulsed stimulus sound with intensity M of 83dB, the interval between the pulses is 25ms, the energy is concentrated at 0.5-6kHz, and the sound structure function is:

wherein the basic stimulation waveform is y (t) sin (2 pi multiplied by 24000t), t is more than or equal to 0 and less than or equal to 100 mus, the time is started from 0, and 602 values are calculated at intervals in total to form a group of stimulation sound waveforms; the strength M assumes a fixed magnitude; and storing the generated basic stimulation data into a head file of the otoacoustic detection project by using simulation software.

3. The method for detecting the probe detector of the otoacoustic abnormal cavity as claimed in claim 1 or 2, which is characterized by comprising the following steps:

the method includes the steps of placing a probe detector, starting testing, and entering a probe detection procedure;

the probe emits basic stimulating sound;

playing short stimulation sound through a pulse stimulation sound system; storing the generated basic stimulation data into a header file of an otoacoustic detection project by using simulation software to realize the acquisition of a sample;

sample data is processed, and a stimulation parameter is calculated:

receiving reflected sound, calculating noise level, and filtering with Hamming window function

Wherein, alpha is 0.46, N is 602, the function processes the noise which is not needed, fast FFT conversion is carried out in the effective frequency range, the energy response of the measured cavity of the reference frequency segment is respectively calculated, and the frequency points are respectively: the energy values of 1KHZ, 2KHZ, 3KHZ, 4KHZ and 5KHZ are used as characteristic values alpha 1, and the number of wave crests appearing in the waveform of 6ms to 15ms of the time domain part is used as a characteristic value alpha 2;

fifthly, in the process of collecting data and calculating the returned sound energy value, counting stability indexes of the transmitted wave and the received wave;

sixth, according to the characteristic parameters alpha 1 and alpha 2 of the fourth step and whether the stability index meets the following requirements in the fifth step: setting 5 data parameter thresholds in the characteristic parameter alpha 1 according to the requirements of DP test or TE test, and setting DP 65 so as to judge the probe index of the cavity to be tested; if so, emitting stimulation sound to meet normal test conditions, and carrying out normal test; if not, the probe is dynamically adjusted, the steps are switched for two seconds, and the test requirements are met until the characteristic parameters and the stability indexes are met.

4. The method for detecting the probe detector of the otoacoustic abnormal cavity according to claim 3, wherein the stability index in the step of the detection method is as follows:

stimulus sound stability: the similarity between each transmitted wave and the previous transmitted wave is more than 90%;

stability of received wave: the similarity between the complete waveform received each time and the waveform received last time is more than 80%;

similarity: euclidean distance using two sets of discrete data

The similarity is calculated, wherein N is a group of received wave lengths, and 602, data1 and data2 are respectively the stimulation sound or the received reflected sound data of the two times before and after.

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