Downloaded 17 times
More Related Content
Similar to Ultrasound effects
Ultrasound effects
- 1.
- 2. CONTENTS • INTRODUCTION • TYPESOF BIOLOGICAL EFFECTS OF ULTRASOUND • THERMAL EFFECTS • NON THERMAL EFFECTS • TYPES OF CAVITATION • STABLE CAVITATION • INERTIAL CAVITATION • OTHER BIOLOGICAL EFFECTS • THERMAL ABLATION • SONOPORATION 2
- 3. INTRODUCTION • Ultrasound isa high frequency mechanical waves that are above the human being range(>20,000Hz) • They are produced by converting the electrical energy into mechanical energy. • When transmission is through biological tissues and under certain conditions, they may cause biological effects. 3
- 4. TYPES BIOLOGICAL EFFECTS OFULTRASOUND MECHANISMS NON THERMAL MECHANICAL CAVITATION THERMAL 4
- 5. THERMAL EFFECTS • Thermaleffects result from the passage of ultrasound waveforms, with transformation of acoustic energy into heat. • This constitutes the major potential adverse effect of obstetric ultrasound, with several reports existing of the deleterious effects of heat on embryos/fetuses in the animal model. • This seems to occur when temperature rises 1.5°C above physiological levels. • Thermal effects depend on the type of tissue exposed, the duration of exposure, ultrasound mode, and the distance between tissue and emission source. 5
- 6. NON THERMAL EFFECTS MECHANICAL •Mechanical effects result from the alternating pressures that are generated. • The main effect occurs because of the interaction between ultrasound waves and gas bubbles present in tissues. 6
- 7. NON THERMAL EFFECTS(Contd..) CAVITATION •Sound waves generate movement in and around gas bubbles, which can affect the surrounding tissues and lead to cavitation. • These bubbles generally of a micron 10 -6 m diameter. • The bubbles increases and decreases in pressure alternatively. 7
- 8. TYPES OF CAVITATION Thereare two types of cavitation: 1. STABLE CAVITATION 2. INERTIAL (NON-STABLE) CAVITATION 8
- 9. STABLE CAVITATION • Stablecavitation describes the steady oscillation of the size of microbubbles as the pressure changes at the focal point • It can induce moderate changes at the cellular level, such as increasing cell membrane permeability to drugs and other molecules. • It also causes mechanical damage , membrane rupture , and sometimes cell lysis. 9
- 10. INERTIAL CAVITATION • Inertialcavitation occurs when the transmitted power is high enough to cause a violent collapse of microbubbles that destroys the tissue • This type of cavitation can be used to create mechanical “lesions” such as those created by histotripsy. • It causes genetic damage in vitro. 10
- 11. Other Biological Effects •Applying focused ultrasound to living tissue results in other effects like tissue destruction, localized drug delivery, or a range of other effects. Tissue Destruction: • Tissue destruction is one of the most common applications of focused ultrasound 11
- 12. THERMAL ABLATION • Themost clinically advanced bioeffect of focused ultrasound, produces cell death in a targeted area with minimal damage to the surrounding tissue • Tissue damage can be accurately controlled using a range of focused ultrasound transducers with different sonication sizes. 12
- 13. SONOPORATION • Cell membranesoften prevent large molecules such as drugs and genes from entering cells and taking effect • This effect, known as sonoporation, can increase the efficacy of drugs and genes in precise areas in the body 13
- 14. REFERENCES • https://www.glowm.com/article/heading/vol-5--surveillance-of- fetal-wellbeing--effects-of-ultrasound-on-biological-tissues-and- cells/id/411403# • Bioeffects_Paper_July_2015.pdf •https://www.slideshare.net/muthuu978/ultrasound-therapy • https://www.slideshare.net/shatham/bioeffect-of-ultra-sound 14
- 15.