WO2021151172A1

WO2021151172A1 - System and method of multichannel recording and digital analysis of respiratory sounds at different levels of inspiratory load

Info

Publication number: WO2021151172A1
Application number: PCT/BA2020/000007
Authority: WO
Inventors: Jasna NUHIĆ; Merima HADŽIABDIĆ; Sabina SELVIĆ-ORUČEVIĆ
Original assignee: Zira D.O.O.
Priority date: 2020-01-29
Filing date: 2020-10-14
Publication date: 2021-08-05

Abstract

The system and method of multichannel signal acquisition and digital analysis of respiratory sounds at different levels of inspiratory load predicts the diagnosis of pulmonary diseases (asthma, pneumonia, pulmonary fibrosis, and chronic obstructive pulmonary disease) performed by analysis of sound signals acquired from five characteristic points on patients' s posterior chest.

Description

SYSTEM AND METHOD OF MULTICHANNEL RECORDING AND DIGITAL ANALYSIS OF RESPIRATORY SOUNDS AT DIFFERENT LEVELS OF INSPIRATORY LOAD

1) TECHNICAL FIELD

The present invention relates to the diagnosis of pulmonary diseases (asthma, pneumonia, pulmonary fibrosis, and chronic obstructive pulmonary disease), performed by the analysis of sound signals collected from five characteristic points on the posterior chest.

According to international classification (IPC) it is classified as: G01H 5/00.

2) TECHNICAL PROBLEM

The main disadvantages of the current state of the art: a) Subjective factor introduced by an expert in auscultatory methods for disease detection, b) Use of invasive diagnostic methods necessary due to auscultation findings, c) Failure to interpret and use hidden patterns in sound signals acquired during loaded breathing which is not utilized nor analyzed, d) Inexistence of uniform procedures of computer respiratory sound analysis for each type of the disease, e) Similarity of sounds in different diseases and f) Signal interference with other biological signals and external noise, which makes diagnostic procedure more difficult for a specialist.

3) BACKGROUND OF THE INVENTION

The auscultatory method is the basic diagnostic method for pulmonary diseases and as such has been known for a long time and is widely used. The basis of the auscultatory method is a stethoscope that serves to listen to the internal sounds of the human body.

Digital versions of a stethoscope are in the market for some time and these variants of a stethoscope can amplify the signal, storage, and visualization, All diagnostic methods based on the use of digitalized sound signal and digital signal processing are associated with only one form of the disease and analyze respiratory sounds without inspiratory load. Existing post-processing digital stethoscope versions classify respiratory sounds without associating sounds with the disease.

4) SUMMARY OF THE INVENTION

4.1. The technical novelty of the present invention eliminates the subjective aspect of auscultation in the conventional diagnosis, thereby further minimizing the unnecessary use of invasive procedures. 4.2. System and methods of digital analysis of respiratory sounds decrease sensitivity to the physiological changes of clinician caused by aging, hearing impairment and the like, and sensitivity to the level of experience that is directly related to the ability to recognize a particular type of respiratory sound and to associate it with the type of disease.

4.3. System and methods of digital analysis of respiratory sounds of the present invention, in relation to the prior state of the art, utilizes the analysis of respiratory sounds during loaded breathing (at different inspiratory pressure levels).

4.4. System and methods of digital analysis of respiratory sounds of the present invention, in relation to the prior state of the art, extracts characteristic biomarkers based on changes in the intensity and type of sound with the change in loading level.

4.5. System and methods of digital analysis of respiratory' sounds of the present invention, in relation to conventional auscultatory methods and systems that record sounds at one characteristic position at the time, perform parallel multi-channel respiratory sound recording on five characteristic points for auscultation.

4.6. System and methods of digital analysis of respiratory sounds of the present invention, in relation to the prior state of the art, classify respiratory sounds, recognizes characteristic biomarkers by additional analysis and associates respiratory sounds with the type of pulmonary disease and thus speed up the diagnostic process.

5) DESCRIPTION OF THE INVENTION

The following text will refer to the details of this alleged embodiment of the invention, one example of which is illustrated.

5.1. System and methods of digital analysis of respiratory sounds according to the present invention, in relation to the previous state of the art, utilizes the measurement of the maximum inspiratory pressure (MIP) and based on it determines the scaled load levels for each patient. Recordings are performed with steps of 12% MIP, up to the 60% limit in the previously defined MIP.

5.2. System and methods of digital analysis of respiratory sounds according to the present invention, in relation to the prior state of the art where only one auscultation head is utilized, uses five auscultation heads positioned at key auscultation points on the posterior chest and trachea, four characteristic points at which the microphones are placed on the surface the patient's back on either side of the spine, in the bottom and near the upper lobe of the right/left lung and the fifth characteristic point is located on the right side at the tracheal level.

5.3. System and methods of digital analysis of respiratory sounds according to the present invention, in relation to the previous state of the art, based on multichannel recording analyzes the spatial distribution of sounds, which is important for localization of pulmonary obstruction. 5.4. System and methods of digital analysis of respiratory sounds according to the present invention, in relation to the prior state of the art which uses temporal isolation of abnormal sounds, uses the intensity of sound at inspiratory cycles at each load level and uses it to extract key biomarkers for each of the diseases considered.

5.5. System and methods of digital analysis of respiratory sounds according to the present invention, in relation to the prior state pf the art, utilizes previously extracted biomarkers to associate subjects with pulmonary disease.

6) APPLICATION METHODS

6.1. The invention is used in healthcare facilities as a first step in the diagnostic procedure of pulmonary diseases.

6.2. The direct user is the doctor and the indirect user is patient.

6.3. The skin does not need to be cleaned prior to usage.

6.4. As clinicians have expertise in the conventional auscultation process, no additional training is required.

6.5. During the procedure, patients are in sitting position, awake, naked up to the waist, in a soundproof room, in a chair without back.

6.6. The device is started by clicking on the start button in the software package.

6.7. Data storage is performed manually after the completion of the procedure where the signals are encrypted and associated with the patient.

6.8. Stored signals are reproduced by clicking on the appropriate control and also displayed in the time domain on the computer.

Claims

PATENT CLAIMS

1. System and method of multichannel recording and digital analysis of respiratory sounds, characterized in that it is based on multichannel recording, the spatial distribution of sounds is localized for localization of pulmonary obstruction by using five identical auscultation heads positioned at key auscultation points, four characteristic points on which acoustic sensors or microphones (4) are placed are located on the surface of the posterior chest of the patient on either side of the spine, in the bottom and near the upper lobe of the right/left lung and the fifth characteristic point is located on the right at the level of the trachea, PCB with amplifier, analog-to-digital converter, filter and communication module (5), communication channel (6) and computer (7), in which the maximum inspiratory pressure (MIP) is measured at different levels of inspiratory load, and based on it determine the scaled load levels for each patient, where it performs in steps of 12% MIP, up to the limit of 60% in the previously specified MIP.

2. The system and method of multichannel recording and digital analysis of respiratory sounds of claim 1, characterized in that it utilizes the sound intensity of inspiratory cycles at each load level and uses it to extract key biomarkers for each of the diseases under consideration.

3. The system and method of multi-channel digital recording and analysis of respiratory sounds of claim 1, characterized in that it uses the extracted biomarkers and associates them with pulmonary diseases.

7) LIST OF USED LABELS

1- Patient

2- Inspirational load

3- Patient's posterior chest

4- Sound sensor (microphone)

5- PCB with amplifier, analog-to-digital converter, filter and communication module

6- Communication

7- Computer

8) BRIEF DESCRIPTION OF THE DRAWINGS

The accompanying drawings, which are part of an invention description illustrate one of the ways of invention utilization and are intended to explain the basic principles of the invention.

Illustration 1 illustrates the principal design of a system for the acquisition, storage, and analysis of respiratory sounds for the purpose of associating them with pulmonary diseases. The illustration shows a patient (I) with a device positioned on the patient's back (3), part of a load-adding system (2), acoustic sensors for sound acquisition (4), a PCB with an amplifier, an analog-to-digital converter, a filter and communication module (5), communication channel (6) and computer (7).