Bioacoustics in Medical Sciences PDF

International Balkan University Skopje Faculty of Dental Medicine Bioacoustics in medical sciences Asst. Prof. Eljesa Murtezi 1  Human body organs and mechanisms generate acoustic signals, including sounds and vibrations, that propagate through the surroundi...

International Balkan University Skopje Faculty of Dental Medicine Bioacoustics in medical sciences Asst. Prof. Eljesa Murtezi 1  Human body organs and mechanisms generate acoustic signals, including sounds and vibrations, that propagate through the surrounding tissues and reach the body surface. They can contain information about the normal or abnormal activity of their sources, i.e., the organs or mechanisms that generated them. Bioacoustics in medicine explores how sound and acoustics are applied to medical diagnosis, treatment, and research. This emerging field combines principles from biology, physics, and engineering to address medical challenges. For instance, cardiovascular or respiratory-induced sounds can be monitored using a stethoscope on the chest’s surface CONCEPT Acoustics is the field of physics, which investigates acoustic oscillations and waves, and process of their excitation, propagation and interaction with substance I. ELECTROMAGNETIC WAVES ✓ Gamma radiation ✓ X radiation ✓ Optical radiation ✓ Radio waves II. MECHANICAL WAVES a. Liquid surface waves b. Elastic waves ✓ Acoustic waves ✓ Seismic waves  Acoustic waves are mechanical waves propagating in elastic medium; through: Gas Liquid Solid Acoustic waves are alteration of the regions or rarefaction and compression of the medium where these propagate. All types of waves can be: Longitudinal waves Direction of particles oscillation coincides with the direction of wave propagation Transverse waves direction of particles oscillation is perpendicular to the direction of the wave propagation In liquid and gas media acoustic waves are longitudinal. In solids they can have both longitudinal and transverse components. Acoustic waves propagate with frequencies from: 0 Hz up to 1012-1013 Hz According to the frequency acoustic waves are divided on four ranges: Infrasound (0 - 16 Hz.) Sound (16 - 20.000 Hz.) Ultrasound (20.000 - 109 Hz.) Hyper-sound (109 - 1013 Hz.) SOUND CHARACTERISTICS OBJECTIVE (Physical) Measured by instruments, regardless of the feelings of the person. SUBJECTIVE (Physiological) Evaluated by the person, regardless of instrument readings. Sound characteristics of the sound Acoustic pressure, P (Pa) Oscillation amplitude, P0 (Pa) Sound intensity, I (W/m2) Level of intensity, L (Bel) Frequency, f (Hz) Oscillation period, T (s) Wavelength, λ (m) Propagation velocity, v (m/s) Harmonic (acoustic) spectrum Frequency, f (Hz) … is the number of full oscillations per unit time. Oscillation period, T (s) …is a quantity reciprocal to frequency (f) It is the time required for one full oscillation. T = 0.67 seconds f = 1.5 Hz Wavelength, λ (m) 𝒗 𝝀= 𝒇 …is the shortest distance between the points of a wave whose oscillation phases differ by 2π distance (m) Wave propagation velocity, v (m) …is the velocity of energy transfer by the wave. The velocity of propagation is different in a different media For example: sound velocity in AIR at 0 oC, v = 331 m/s at 20 oC,v = 340 m/s in LIQUIDS v = 0.7 km/s Water v =1.34 km/s in SOLIDS v = 1.5-7 km/s DIAGNOSTIC APPLICATIONS a. Imaging Ultrasound High-frequency sound waves create images of internal body structures. Obstetrics, cardiology, abdominal imaging 3D/4D ultrasound, Doppler imaging for blood flow Elastography Using sound waves to measure tissue stiffness for cancer detection. DIAGNOSTIC APPLICATIONS b. Non-Invasive Diagnostics Phonocardiography Recording heart sounds for detecting murmurs or valve issues. Lung Sound Analysis Diagnosing respiratory diseases (e.g., asthma, pneumonia). Voice Analysis Early detection of neurological conditions (e.g., Parkinson’s disease, ALS). Lung Sound Analysis THERAPEUTIC APPLICATIONS a. High-Intensity Focused Ultrasound (HIFU) Non-invasive treatment using focused sound waves to destroy tumors or tissues (e.g., prostate cancer, uterine fibroids). b. Lithotripsy Using acoustic waves to break kidney stones into smaller fragments for easier passage. c. Ultrasound in Rehabilitation Therapeutic ultrasound for pain relief, reducing inflammation, and promoting tissue healing. WEARABLE AND ASSISTIVE BIOACOUSTICS Hearing Aids and Cochlear Implants Amplify or simulate sound for the hearing impaired. Wearable Monitors Devices that use bioacoustics to monitor vital signs, such as respiratory rate and heart sounds. Speech Generating Devices Bioacoustics technologies aiding in voice synthesis for individuals with speech impairments. Thank you for your attention