Therapeutic ultrasound uses high-frequency sound waves to stimulate tissues beneath the skin's surface. It offers thermal and non-thermal effects. Thermal effects increase heat and metabolism, while non-thermal effects are from cavitation and acoustic streaming. Proper technique and a coupling medium are required for ultrasound transmission through tissues. The beam is non-uniform near the transducer due to interference. Pulsed ultrasound and phonophoresis are also described. Contraindications include pregnancy, malignancy, and bleeding tissues. Precautions include using the lowest intensity and moving the applicator.
Ultrasound therapy uses high frequency sound waves to create effects in the body. There are thermal and non-thermal effects. Thermal effects occur when ultrasound is used to heat tissues, potentially increasing flexibility. Non-thermal effects are thought to be from cavitation and acoustic streaming. Cavitation involves gas bubble formation, while acoustic streaming disturbs fluid flow. Together these effects can increase cell membrane permeability and metabolic activity. Proper ultrasound dosage considers frequency, intensity, pulse ratio, and treatment duration to target specific depths and achieve desired effects while avoiding harm.
This document summarizes key aspects of ultrasound therapy. It discusses ultrasound transmission and propagation through tissues, the components of an ultrasound generator including the transducer and piezoelectric effect, physiological effects including thermal and non-thermal effects, techniques for application, indications and contraindications.
This document discusses ultrasound, including its physics, production, effects, and therapeutic uses. It defines ultrasound and discusses how it is produced using the piezoelectric effect. The main physical effects of ultrasound are heating, cavitation, acoustic streaming, and microstreaming. Thermally, ultrasound can increase tissue extensibility and reduce pain and muscle spasm. Non-thermally, it can increase membrane permeability and ion diffusion through cavitation. The document outlines appropriate ultrasound parameters and treatment techniques to maximize benefits and minimize risks.
This document discusses ultrasound therapy and properties of ultrasound. It defines ultrasound as sound waves with frequencies above the human hearing range. Therapeutic ultrasound uses frequencies between 0.5 to 5 MHz. Ultrasound is produced using the piezoelectric effect where crystals expand and contract when electric current is passed through. Key ultrasound properties discussed are intensity, beam uniformity, duty cycle, frequencies, and effective radiating area. Near and far ultrasound fields are also explained.
This document discusses ultrasound and its use in physiotherapy. It begins by defining ultrasound and its frequencies. It then covers the components of an ultrasound machine, treatment parameters, transmission methods, and the properties of ultrasound like reflection, refraction and attenuation. The document outlines ultrasound's physiological effects and its therapeutic uses for conditions like soft tissue injuries and inflammation. It provides guidance on testing equipment, treatment methods, dosages, contraindications, and precautions when using ultrasound.
Ultrasound uses high frequency sound waves to produce either thermal or non-thermal effects in tissues. It works by using a transducer that converts electrical energy into longitudinal sound waves through the piezoelectric effect. These waves can be used for diagnostic imaging or to accelerate tissue healing by increasing blood flow and the activity of immune cells through both thermal and non-thermal mechanisms of action. The document provides details on ultrasound wave properties, transducer types, intensities, and clinical applications.
Ultrasonic therapy uses high-frequency sound waves to treat injuries and conditions. It works by generating ultrasound using piezoelectric crystals that expand and contract in response to an electrical current. This creates alternating compressions and rarefactions that transmit energy into the body. Ultrasound has both thermal and non-thermal physiological effects, such as generating heat in tissues through absorption and cavitation, microstreaming, and mechanical tissue massage. Its heating properties can accelerate healing while its non-thermal effects may increase cell permeability and movement. Ultrasonic therapy is used to reduce pain and swelling and aid in tissue repair by stimulating fibroblasts and collagen production.
Therapeutic ultrasound uses high frequency sound waves to produce effects in the body. It is generated using piezoelectric crystals that vibrate when electric current is applied. Ultrasound has various physiological effects including chemical reactions, increased permeability, cavitation, and heat. It is used clinically by applying ultrasound gel and transducer to the skin to produce effects like reduced edema and increased tendon flexibility. Precautions must be taken with open wounds, impaired sensation, pregnancy, and other conditions. Contraindications include pregnancy, metastasis, and lack of sensation.
Ultrasound therapy uses high frequency sound waves to create effects in the body. There are thermal and non-thermal effects. Thermal effects occur when ultrasound is used to heat tissues, potentially increasing flexibility. Non-thermal effects are thought to be from cavitation and acoustic streaming. Cavitation involves gas bubble formation, while acoustic streaming disturbs fluid flow. Together these effects can increase cell membrane permeability and metabolic activity. Proper ultrasound dosage considers frequency, intensity, pulse ratio, and treatment duration to target specific depths and achieve desired effects while avoiding harm.
This document summarizes key aspects of ultrasound therapy. It discusses ultrasound transmission and propagation through tissues, the components of an ultrasound generator including the transducer and piezoelectric effect, physiological effects including thermal and non-thermal effects, techniques for application, indications and contraindications.
This document discusses ultrasound, including its physics, production, effects, and therapeutic uses. It defines ultrasound and discusses how it is produced using the piezoelectric effect. The main physical effects of ultrasound are heating, cavitation, acoustic streaming, and microstreaming. Thermally, ultrasound can increase tissue extensibility and reduce pain and muscle spasm. Non-thermally, it can increase membrane permeability and ion diffusion through cavitation. The document outlines appropriate ultrasound parameters and treatment techniques to maximize benefits and minimize risks.
This document discusses ultrasound therapy and properties of ultrasound. It defines ultrasound as sound waves with frequencies above the human hearing range. Therapeutic ultrasound uses frequencies between 0.5 to 5 MHz. Ultrasound is produced using the piezoelectric effect where crystals expand and contract when electric current is passed through. Key ultrasound properties discussed are intensity, beam uniformity, duty cycle, frequencies, and effective radiating area. Near and far ultrasound fields are also explained.
This document discusses ultrasound and its use in physiotherapy. It begins by defining ultrasound and its frequencies. It then covers the components of an ultrasound machine, treatment parameters, transmission methods, and the properties of ultrasound like reflection, refraction and attenuation. The document outlines ultrasound's physiological effects and its therapeutic uses for conditions like soft tissue injuries and inflammation. It provides guidance on testing equipment, treatment methods, dosages, contraindications, and precautions when using ultrasound.
Ultrasound uses high frequency sound waves to produce either thermal or non-thermal effects in tissues. It works by using a transducer that converts electrical energy into longitudinal sound waves through the piezoelectric effect. These waves can be used for diagnostic imaging or to accelerate tissue healing by increasing blood flow and the activity of immune cells through both thermal and non-thermal mechanisms of action. The document provides details on ultrasound wave properties, transducer types, intensities, and clinical applications.
Ultrasonic therapy uses high-frequency sound waves to treat injuries and conditions. It works by generating ultrasound using piezoelectric crystals that expand and contract in response to an electrical current. This creates alternating compressions and rarefactions that transmit energy into the body. Ultrasound has both thermal and non-thermal physiological effects, such as generating heat in tissues through absorption and cavitation, microstreaming, and mechanical tissue massage. Its heating properties can accelerate healing while its non-thermal effects may increase cell permeability and movement. Ultrasonic therapy is used to reduce pain and swelling and aid in tissue repair by stimulating fibroblasts and collagen production.
Therapeutic ultrasound uses high frequency sound waves to produce effects in the body. It is generated using piezoelectric crystals that vibrate when electric current is applied. Ultrasound has various physiological effects including chemical reactions, increased permeability, cavitation, and heat. It is used clinically by applying ultrasound gel and transducer to the skin to produce effects like reduced edema and increased tendon flexibility. Precautions must be taken with open wounds, impaired sensation, pregnancy, and other conditions. Contraindications include pregnancy, metastasis, and lack of sensation.
Ultrasonography uses high frequency sound waves to produce images of internal organs and structures. Sound waves are transmitted into the body using a transducer, which converts electrical signals to sound and vice versa. Reflections from tissues are detected and used to construct images showing anatomical structures. Key physics principles include velocity, frequency, wavelength, and reflection based on acoustic impedance differences between tissues. Proper transducer design and focused beams are important for optimizing image quality and resolution.
This document discusses key concepts in ultrasound therapy. It defines ultrasound as mechanical energy consisting of areas of compression and rarefaction. Frequency is the number of compression/rarefaction cycles per second. Propagation speed depends on the medium and determines wavelength. Accoustic impedance describes resistance to an ultrasound beam. Reflection and refraction occur at impedance boundaries. Attenuation reduces intensity as ultrasound propagates through tissue. Intensity is further defined as spatial peak, average, temporal peak and average.
Ultrasonic diathermy uses high frequency sound waves generated by a piezoelectric transducer to create heat deep in tissues through vibration, promoting blood flow to treat diseases of the peripheral nervous system, muscles, and skin ulcers. The heat effect is similar to a deep tissue massage without pain. Ultrasonic waves can be delivered continuously or in pulses at frequencies between 800 kHz to 1 MHz for localized treatment of conditions like muscle sprains, strains, and adhesions.
Therapeutic Ultrasound for Physiotherapy studentsSaurab Sharma
This lecture intends to provide general outline about the uses, parameters, precautions and contraindications of therapeutic ultrasound for undergraduate physiotherapy students at Kathmandu University School of Medical Sciences, Nepal. After the lecture, students will explore the evidences about current practices of therapeutic ultrasound in various musculoskeletal pain conditions, critically appraise them and present the evidences to the class.
This document provides an overview of ultrasound physics basics. It discusses how ultrasound uses sound waves between 10-20 MHz to generate images. Sound waves are longitudinal waves that travel through materials at different speeds depending on compressibility and density. Ultrasound imaging works by transmitting pulses into the body and receiving echoes, with transducers converting between electrical and sound signals. Factors like frequency, beam characteristics, and tissue interactions impact the resulting images and potential artifacts. Understanding ultrasound physics principles is important for optimizing scans and interpreting images.
Microwave diathermy (MWD) uses electromagnetic radiation in the microwave frequency range to generate heat in tissue. MWD uses a magnetron to produce microwaves with frequencies commonly between 300 MHz to 300 GHz. These short wavelength microwaves generate strong electrical fields that cause heating through ionic movements and molecular distortion within tissues. MWD provides superficial heating that is more localized than shortwave diathermy and penetrates deeper than infrared radiation. Key uses of MWD include reducing pain, swelling and muscle spasm in inflammatory conditions like tendinitis as well as accelerating healing for injuries and infections.
Ultrasound Physics Made easy - By Dr Chandni WadhwaniChandni Wadhwani
History of ultrasound, Principle of Ultrasound.
Ultrasound wave and its interactions
Ultrasound machine and its parts, Image display, Artifacts and their clinical importance
what is Doppler ultrasound, Elastography and Recent advances in field of ultrasound.
Safety issues in ultrasound.
Ultrasound uses high frequency sound waves that are transmitted into the body. The echoes that bounce back are used to form images of tissues and organs. Higher frequencies provide better resolution but penetrate less deeply. Ultrasound is used for diagnostic medical imaging and to guide procedures by providing real-time visualization of internal structures. It has advantages of being noninvasive, having no known health effects, and being relatively inexpensive compared to other imaging modalities.
This document discusses ultrasound physics and provides details on:
1. Ultrasound is generated using piezoelectric crystals that vibrate when electric current is applied, generating sound waves. Echoes from tissues are detected and used to form images.
2. Different ultrasound probe types (linear, convex, phased array) use different crystal arrangements and frequencies suited to imaging different anatomies.
3. Safety studies have found no harm from ultrasound exposure levels used for medical imaging, as temperatures increases are minimal. Ultrasound is safe to use during pregnancy.
This document discusses ultrasound and electrotherapy. It describes how ultrasound uses mechanical vibration to generate heat in tissues. Different coupling methods like gels or immersion can be used depending on the treatment area. Electrotherapy can stimulate muscles or nerves to help with conditions like pain, edema, or muscle atrophy. Electrical currents are used to induce muscle contraction or stimulate sensory nerves according to the gate control or descending pain theories of treatment. Placement of electrodes can target specific tissues or structures.
An ultrasound machine uses a transducer probe to produce and receive ultrasound pulses that are used to form images of internal tissues and organs. It consists of a transducer, central processing unit, keyboard, display, storage device and printer. The transducer contains piezoelectric crystals that convert electrical signals to ultrasound pulses and reflected ultrasound echoes back to electrical signals. These signals are processed by the CPU to produce images on the display based on differences in tissue reflection and absorption of the ultrasound pulses. Ultrasound machines are used for diagnostic purposes in various medical fields such as cardiology, gynecology and urology.
Ultrasonic therapy uses high frequency sound waves above the range of human hearing to provide therapeutic effects. It works by using an electrical current to power transducers that convert the current into ultrasonic waves. These waves can then be used for diagnostic imaging, surgery, and physiotherapy. Therapeutically, ultrasonic waves create effects through thermal, mechanical, and chemical/biological interactions with tissues. Common uses are for musculoskeletal conditions like sprains, tendinitis, and arthritis. Proper application involves selecting an appropriate intensity, duration, and frequency setting based on the condition being treated. Risks like burns and tissue damage require precautions like starting with low intensities and using pulsed rather than continuous waves in some cases.
This document contains a lecture on ultrasound physics and principles. It discusses topics like how ultrasound pulses propagate through different media, ultrasound beam formation, spatial and temporal resolution, transducer properties, and attenuation compensation. Multiple choice questions are included at the end to test understanding of concepts like axial resolution, transducer crystals, and phased array transducers.
Applications of Ultrasound in MedicinePranay Dutta
Ultrasound uses high-frequency sound waves to produce images of internal organs and structures. It has many medical applications. Ultrasound works by sending pulses of sound into the body that bounce off tissues and create echoes. These echoes are converted into electrical signals and processed to form images. The images provide information about anatomy, abnormal growths, and blood flow.
Therapeutic ultrasound uses sound waves to treat injuries and other conditions. It can be used for imaging, physical therapy, and tissue destruction. Ultrasound works through thermal and non-thermal effects. Thermal effects include increased tissue flexibility and blood flow through localized heating. Non-thermal effects include cavitation and mechanical alterations to cell membranes. Common uses are for joint and muscle issues, reducing pain and spasms, and accelerating wound healing. Precautions must be taken to avoid sensitive areas and ensure safe operation. Clinical decision making considers the injury stage, pathology location, needed tissue heating, and implants.
Ultrasound uses high frequency sound waves to image internal structures. A transducer converts electrical pulses into ultrasound pulses and reflected sound waves back into electrical signals. Tissues reflect sound differently allowing visualization. Higher frequencies improve resolution but reduce penetration. Ultrasound has various medical uses like imaging fetuses, organs and detecting abnormalities by interpreting echo patterns. It provides real-time images without radiation unlike other modalities.
This document discusses various uses of ultrasound waves. It begins by defining ultrasound as sound waves with a frequency above the human hearing range. It then lists 10 common uses of ultrasound, including for cleaning, disintegration, humidifiers, welding, weapons, and various applications in medicine like sonography and therapy. Each use is then discussed in more detail with explanations and examples. The document concludes that ultrasound has diverse uses across many fields like medicine, industry, and nature.
This document discusses non-thermal effects of diagnostic ultrasound, specifically radiation force and its potential biological effects. It outlines ultrasound basics and physics, defines key terms, and explores mechanical effects not related to heating, including cavitation, acoustic radiation force, and acoustic streaming which can cause fluid movement. Observations of effects on bone, lung, heart, perception, and development are provided, such as ultrasound accelerating bone healing and potentially altering neural migration through radiation force.
Ultrasound therapy uses high frequency sound waves to generate heat deep in tissues for therapeutic purposes. A generator sets the ultrasound frequency between 1-3 MHz, with higher frequencies penetrating less deeply. Pulsed ultrasound is safer as it allows time for heat to dissipate between pulses. Non-thermal effects include cavitation, acoustic streaming, and micromassage. Ultrasound promotes healing in acute injuries by stimulating inflammatory responses and collagen synthesis. It helps remodel scar tissue and accelerate wound healing in chronic injuries by increasing membrane permeability. Common uses are for varicose ulcers, pressure sores, pain relief in herpes zoster and back pain. Moving the transducer head prevents heat build up and damage from standing waves.
Therapeutic ultrasound uses high frequency sound waves to produce thermal and non-thermal effects in tissues. It is commonly used by athletic trainers to induce deep heating. When used properly by a competent clinician, it can provide positive outcomes, but improper use provides few benefits. Key components of an ultrasound device include the generator, crystal, soundhead, and applicator. Treatment parameters like frequency, intensity, time, and area treated must be set correctly to achieve the desired therapeutic effect safely and effectively.
Ultrasonography uses high frequency sound waves to produce images of internal organs and structures. Sound waves are transmitted into the body using a transducer, which converts electrical signals to sound and vice versa. Reflections from tissues are detected and used to construct images showing anatomical structures. Key physics principles include velocity, frequency, wavelength, and reflection based on acoustic impedance differences between tissues. Proper transducer design and focused beams are important for optimizing image quality and resolution.
This document discusses key concepts in ultrasound therapy. It defines ultrasound as mechanical energy consisting of areas of compression and rarefaction. Frequency is the number of compression/rarefaction cycles per second. Propagation speed depends on the medium and determines wavelength. Accoustic impedance describes resistance to an ultrasound beam. Reflection and refraction occur at impedance boundaries. Attenuation reduces intensity as ultrasound propagates through tissue. Intensity is further defined as spatial peak, average, temporal peak and average.
Ultrasonic diathermy uses high frequency sound waves generated by a piezoelectric transducer to create heat deep in tissues through vibration, promoting blood flow to treat diseases of the peripheral nervous system, muscles, and skin ulcers. The heat effect is similar to a deep tissue massage without pain. Ultrasonic waves can be delivered continuously or in pulses at frequencies between 800 kHz to 1 MHz for localized treatment of conditions like muscle sprains, strains, and adhesions.
Therapeutic Ultrasound for Physiotherapy studentsSaurab Sharma
This lecture intends to provide general outline about the uses, parameters, precautions and contraindications of therapeutic ultrasound for undergraduate physiotherapy students at Kathmandu University School of Medical Sciences, Nepal. After the lecture, students will explore the evidences about current practices of therapeutic ultrasound in various musculoskeletal pain conditions, critically appraise them and present the evidences to the class.
This document provides an overview of ultrasound physics basics. It discusses how ultrasound uses sound waves between 10-20 MHz to generate images. Sound waves are longitudinal waves that travel through materials at different speeds depending on compressibility and density. Ultrasound imaging works by transmitting pulses into the body and receiving echoes, with transducers converting between electrical and sound signals. Factors like frequency, beam characteristics, and tissue interactions impact the resulting images and potential artifacts. Understanding ultrasound physics principles is important for optimizing scans and interpreting images.
Microwave diathermy (MWD) uses electromagnetic radiation in the microwave frequency range to generate heat in tissue. MWD uses a magnetron to produce microwaves with frequencies commonly between 300 MHz to 300 GHz. These short wavelength microwaves generate strong electrical fields that cause heating through ionic movements and molecular distortion within tissues. MWD provides superficial heating that is more localized than shortwave diathermy and penetrates deeper than infrared radiation. Key uses of MWD include reducing pain, swelling and muscle spasm in inflammatory conditions like tendinitis as well as accelerating healing for injuries and infections.
Ultrasound Physics Made easy - By Dr Chandni WadhwaniChandni Wadhwani
History of ultrasound, Principle of Ultrasound.
Ultrasound wave and its interactions
Ultrasound machine and its parts, Image display, Artifacts and their clinical importance
what is Doppler ultrasound, Elastography and Recent advances in field of ultrasound.
Safety issues in ultrasound.
Ultrasound uses high frequency sound waves that are transmitted into the body. The echoes that bounce back are used to form images of tissues and organs. Higher frequencies provide better resolution but penetrate less deeply. Ultrasound is used for diagnostic medical imaging and to guide procedures by providing real-time visualization of internal structures. It has advantages of being noninvasive, having no known health effects, and being relatively inexpensive compared to other imaging modalities.
This document discusses ultrasound physics and provides details on:
1. Ultrasound is generated using piezoelectric crystals that vibrate when electric current is applied, generating sound waves. Echoes from tissues are detected and used to form images.
2. Different ultrasound probe types (linear, convex, phased array) use different crystal arrangements and frequencies suited to imaging different anatomies.
3. Safety studies have found no harm from ultrasound exposure levels used for medical imaging, as temperatures increases are minimal. Ultrasound is safe to use during pregnancy.
This document discusses ultrasound and electrotherapy. It describes how ultrasound uses mechanical vibration to generate heat in tissues. Different coupling methods like gels or immersion can be used depending on the treatment area. Electrotherapy can stimulate muscles or nerves to help with conditions like pain, edema, or muscle atrophy. Electrical currents are used to induce muscle contraction or stimulate sensory nerves according to the gate control or descending pain theories of treatment. Placement of electrodes can target specific tissues or structures.
An ultrasound machine uses a transducer probe to produce and receive ultrasound pulses that are used to form images of internal tissues and organs. It consists of a transducer, central processing unit, keyboard, display, storage device and printer. The transducer contains piezoelectric crystals that convert electrical signals to ultrasound pulses and reflected ultrasound echoes back to electrical signals. These signals are processed by the CPU to produce images on the display based on differences in tissue reflection and absorption of the ultrasound pulses. Ultrasound machines are used for diagnostic purposes in various medical fields such as cardiology, gynecology and urology.
Ultrasonic therapy uses high frequency sound waves above the range of human hearing to provide therapeutic effects. It works by using an electrical current to power transducers that convert the current into ultrasonic waves. These waves can then be used for diagnostic imaging, surgery, and physiotherapy. Therapeutically, ultrasonic waves create effects through thermal, mechanical, and chemical/biological interactions with tissues. Common uses are for musculoskeletal conditions like sprains, tendinitis, and arthritis. Proper application involves selecting an appropriate intensity, duration, and frequency setting based on the condition being treated. Risks like burns and tissue damage require precautions like starting with low intensities and using pulsed rather than continuous waves in some cases.
This document contains a lecture on ultrasound physics and principles. It discusses topics like how ultrasound pulses propagate through different media, ultrasound beam formation, spatial and temporal resolution, transducer properties, and attenuation compensation. Multiple choice questions are included at the end to test understanding of concepts like axial resolution, transducer crystals, and phased array transducers.
Applications of Ultrasound in MedicinePranay Dutta
Ultrasound uses high-frequency sound waves to produce images of internal organs and structures. It has many medical applications. Ultrasound works by sending pulses of sound into the body that bounce off tissues and create echoes. These echoes are converted into electrical signals and processed to form images. The images provide information about anatomy, abnormal growths, and blood flow.
Therapeutic ultrasound uses sound waves to treat injuries and other conditions. It can be used for imaging, physical therapy, and tissue destruction. Ultrasound works through thermal and non-thermal effects. Thermal effects include increased tissue flexibility and blood flow through localized heating. Non-thermal effects include cavitation and mechanical alterations to cell membranes. Common uses are for joint and muscle issues, reducing pain and spasms, and accelerating wound healing. Precautions must be taken to avoid sensitive areas and ensure safe operation. Clinical decision making considers the injury stage, pathology location, needed tissue heating, and implants.
Ultrasound uses high frequency sound waves to image internal structures. A transducer converts electrical pulses into ultrasound pulses and reflected sound waves back into electrical signals. Tissues reflect sound differently allowing visualization. Higher frequencies improve resolution but reduce penetration. Ultrasound has various medical uses like imaging fetuses, organs and detecting abnormalities by interpreting echo patterns. It provides real-time images without radiation unlike other modalities.
This document discusses various uses of ultrasound waves. It begins by defining ultrasound as sound waves with a frequency above the human hearing range. It then lists 10 common uses of ultrasound, including for cleaning, disintegration, humidifiers, welding, weapons, and various applications in medicine like sonography and therapy. Each use is then discussed in more detail with explanations and examples. The document concludes that ultrasound has diverse uses across many fields like medicine, industry, and nature.
This document discusses non-thermal effects of diagnostic ultrasound, specifically radiation force and its potential biological effects. It outlines ultrasound basics and physics, defines key terms, and explores mechanical effects not related to heating, including cavitation, acoustic radiation force, and acoustic streaming which can cause fluid movement. Observations of effects on bone, lung, heart, perception, and development are provided, such as ultrasound accelerating bone healing and potentially altering neural migration through radiation force.
Ultrasound therapy uses high frequency sound waves to generate heat deep in tissues for therapeutic purposes. A generator sets the ultrasound frequency between 1-3 MHz, with higher frequencies penetrating less deeply. Pulsed ultrasound is safer as it allows time for heat to dissipate between pulses. Non-thermal effects include cavitation, acoustic streaming, and micromassage. Ultrasound promotes healing in acute injuries by stimulating inflammatory responses and collagen synthesis. It helps remodel scar tissue and accelerate wound healing in chronic injuries by increasing membrane permeability. Common uses are for varicose ulcers, pressure sores, pain relief in herpes zoster and back pain. Moving the transducer head prevents heat build up and damage from standing waves.
Therapeutic ultrasound uses high frequency sound waves to produce thermal and non-thermal effects in tissues. It is commonly used by athletic trainers to induce deep heating. When used properly by a competent clinician, it can provide positive outcomes, but improper use provides few benefits. Key components of an ultrasound device include the generator, crystal, soundhead, and applicator. Treatment parameters like frequency, intensity, time, and area treated must be set correctly to achieve the desired therapeutic effect safely and effectively.
Therapeutic ultrasound uses high frequency sound waves to produce thermal and nonthermal effects in tissues. It selectively heats tissues high in collagen like tendons and ligaments. Key parameters include frequency (1-3 MHz), intensity (0.5-3 W/cm2), and treatment time. Ultrasound increases blood flow, tissue extensibility, and metabolism to enhance soft tissue healing and reduce pain. It is used for conditions like tendinitis, bursitis, and muscle strains.
This document provides an overview of ultrasound basics, including its history, principles of operation, interactions with tissue, machine components, imaging modes, artifacts, Doppler, elastography, and safety. Key points covered include how ultrasound works via the piezoelectric effect, factors that affect resolution, common artifacts and their clinical value, applications of Doppler and elastography, and that diagnostic ultrasound has been deemed safe by medical organizations.
This document provides an overview of ultrasound basics, including its history, principles of operation, interactions with tissue, machine components, imaging modes, artifacts, Doppler, elastography, and safety. Key points covered include how ultrasound works via the piezoelectric effect, factors that affect resolution, common artifacts and their clinical value, applications of Doppler and elastography, and that diagnostic ultrasound has been deemed safe by medical organizations.
Ultrasound uses high-frequency sound waves to create images of the inside of the body. It works by transmitting sound pulses into the body using a probe. When the pulses hit boundaries between tissues, some of the sound waves are reflected back to the probe. The machine calculates the distance to tissues and organs based on the speed of sound and time of the echo returns, forming a 2D image. Common medical uses of ultrasound include imaging organs in the abdomen and monitoring fetuses during pregnancy.
This document provides an overview of therapeutic ultrasound. It defines ultrasound as a mechanical wave with frequencies too high for human hearing. Ultrasound is generated using piezoelectric crystals that convert electrical oscillations to mechanical vibrations. As ultrasound propagates through tissues, it undergoes attenuation and is absorbed differently based on tissue properties. Pulsed ultrasound is commonly used to allow time for heat dissipation between pulses. Key physical phenomena like reflection, refraction, and absorption influence how ultrasound is transmitted and interacts with tissues.
This document provides an overview of ultrasound physics concepts including:
- How ultrasound waves interact with tissue through attenuation, reflection, scattering, refraction, and diffraction.
- Key properties of ultrasound waves like wavelength, frequency, amplitude, and acoustic impedance.
- Factors that determine image resolution such as transducer frequency and beam focusing.
- Common artefacts that can occur like reverberation, side lobes, and multi-path artefacts.
- The importance of understanding ultrasound physics principles to optimize image quality and avoid misdiagnosis.
Ultrasound uses sound waves to produce images of internal organs and tissues. Sound waves are transmitted into the body and the echoes produced by reflections from structures and tissues are detected. Three key points:
1) Ultrasound transducers convert electrical pulses into sound waves which penetrate the body and receive the echoes. Piezoelectric crystals in the transducer perform this function.
2) Reflected sound waves are displayed as images on screen to visualize internal structures. The brightness of each pixel depends on the strength of reflection.
3) Different transducer designs like linear arrays and curved arrays allow imaging of different body regions. Imaging modes like B-mode show anatomical structures while M-mode depicts motion.
Vascular ultrasound uses sound waves to image blood vessels. It combines real-time imaging (B-mode) with Doppler to show anatomy and blood flow. Ultrasound is generated by piezoelectric crystals in the transducer that convert electrical signals to sound waves. Reflected sound waves are converted back to electrical signals to form images. Factors like frequency, amplitude, and wavelength determine image quality and depth of penetration. Ultrasound provides information on vessel structure and blood flow velocity through Doppler modes.
Physics of ultrasound and echocardiographyjeetshitole
The document discusses the history and physics of ultrasound imaging and echocardiography. It covers how ultrasound waves interact with tissues through reflection, scattering, attenuation and absorption. It describes how piezoelectric transducers convert electrical signals to ultrasound and vice versa to produce images. Imaging can be done in various modes like A-mode, B-mode, M-mode and 2D to visualize cardiac structures and function at different resolutions and depths.
This document reviews the evidence for using therapeutic ultrasound to treat soft tissue injuries. While laboratory studies have shown ultrasound can have physiological effects like increasing blood flow and stimulating tissue repair, there is surprisingly little clinical evidence that it provides benefits for soft tissue injuries. The few clinical studies that have been done are of low quality and do not show ultrasound is effective at reducing pain. More high-quality research is still needed to determine if ultrasound truly helps or lacks effect for soft tissue conditions.
THERAPEUTIC ULTRASOUND: A PRACTICAL APPROACH BY MINED ACADEMYMINED ACADEMY
Therapeutic ultrasound can be used for both diagnostic imaging and treatment purposes. It produces longitudinal ultrasound waves that can have thermal or non-thermal effects on tissues depending on the mode of application. Common applications include soft tissue healing, pain relief, and bone fracture treatment. Proper parameters including frequency, intensity, duration and mode of application are important to provide benefits while avoiding risks like burns or tissue damage.
This document provides an overview of ultrasound, including its physics, production, effects, uses, and treatment parameters. It defines ultrasound and discusses how it is produced via the piezoelectric effect. The key effects of ultrasound are thermal (heating tissues) and non-thermal (cavitation, acoustic streaming, microstreaming). Ultrasound has therapeutic uses for pain relief, increasing tissue extensibility, and promoting healing. Treatment parameters like intensity, duty cycle, and frequency are described.
Ultrasound uses high-frequency sound waves to create images of the inside of the body. It works by passing an electric current through a transducer, causing crystals inside to vibrate and produce ultrasound waves. These waves reflect off tissues and organs and return echoes that are converted into images. The frequency of the ultrasound waves determines properties like axial resolution and penetration depth. Ultrasound is widely used for medical imaging due to being noninvasive, painless, and less expensive than other imaging methods.
This document provides an overview of the physics behind conventional and advanced ultrasound imaging. It begins with introductions to sound waves and ultrasound, then discusses key ultrasound properties like frequency, wavelength, velocity and attenuation. It explains how ultrasound interacts with tissues using principles of reflection, refraction and acoustic impedance. The role of transducers in generating and receiving ultrasound is covered. Methods for focusing beams, steering angles and displaying images are described. Tradeoffs between resolution, penetration depth and frame rates in image creation are also summarized. Overall, the document concisely outlines core physics concepts underlying modern ultrasound technology.
This document discusses therapeutic ultrasound. It begins by defining sound and ultrasound, noting that ultrasound refers to sound waves above 20 kHz. It then compares the properties of sound waves and light waves. The rest of the document discusses various topics related to therapeutic ultrasound in detail, including the characteristics of sound waves, properties such as transmission, reflection, refraction, diffraction, absorption and scattering. It also covers topics like ultrasound production, coupling agents, effective radiating area, beam nonuniformity ratio, types of ultrasound beams, and physiological effects. Laboratory activities for orientation to ultrasound equipment and testing transducers are also outlined.
The document discusses various topics related to ultrasound and knobology. It begins with an introduction to ultrasound, covering the properties of ultrasound including frequency, wavelength, velocity and attenuation. It then discusses the principles of ultrasound imaging using the pulse-echo technique. The document covers ultrasound tissue interaction through reflection, refraction, absorption and scattering. It also discusses ultrasound instrumentation components including transducers, imaging modes like B-mode and special imaging techniques like harmonic imaging. Finally, it provides a brief introduction to knobology.
This document provides an overview of ultrasound physics basics. It discusses how ultrasound uses sound waves between 10-20 MHz to generate images. Sound waves are longitudinal waves that travel through materials at different speeds depending on compressibility and density. Ultrasound imaging works by transmitting pulses into the body and receiving echoes, with transducers converting between electrical and sound signals. Factors like frequency, beam characteristics, and tissue interactions impact the resulting images and potential artifacts. Understanding ultrasound physics principles is important for optimizing scans and interpreting images.
This document provides information on traffic rules and safety. It discusses important rules for vehicles and pedestrians, such as not stopping on pedestrian crossings or having more than two people on a motorcycle. It also shows data on the rising number of accidents from 2000 to 2015. Additional topics covered include traffic control, traffic lights, basic safety rules like wearing helmets, and causes of accidents like speeding and drunk driving. The document emphasizes the importance of safety awareness and following precautions to prevent road accidents.
The scapula is a flat, triangular bone located on the posterior aspect of the rib cage. It has three borders and three angles. Several muscles originate on the scapula, including the subscapularis, teres major, teres minor, and trapezius. The scapula acts to rotate the shoulder joint and stabilize the shoulder girdle.
Whirpool bath (indication and introduction)Iram Anwar
Whirlpool baths use warm water and jets of water or air to produce turbulence, combining the therapeutic effects of heat and gentle massage. There are several types of whirlpool baths suited for different body parts. Whirlpool baths are used to improve circulation, reduce pain and stiffness, clean wounds, and prepare areas for exercises by relaxing muscles. Contraindications include infections, bleeding, or impaired circulation. Whirlpool baths provide benefits for conditions like arthritis, injuries, and post-surgical recovery.
Ultraviolate radiation and their therapeutic effectIram Anwar
UVR covers a small part of the electromagnetic spectrum between visible light and X-rays. It is produced by mercury vapor lamps and fluorescent tubes in medical devices. UVR has both local and general therapeutic effects, such as reducing psoriasis and acne lesions locally through DNA damage and inflammation, and increasing vitamin D production and immunity generally. However, it also has risks like skin cancer and contraindications for people with certain medical conditions. PUVA combines oral or topical psoralens with UVA to treat severe skin diseases.
This document discusses four main types of lasers: solid state lasers, gas lasers, dye lasers, and semiconductor lasers. Solid state lasers use a solid gain medium doped with rare earth elements and emit wavelengths including infrared. Gas lasers are common lasers like HeNe and CO2 that emit visible or infrared. Dye lasers use organic dyes in liquid solution as a tunable gain medium across many wavelengths. Semiconductor lasers are small electronic devices like diode lasers that operate similarly to LEDs but produce coherent laser light.
Traces of ethnocentrism (the park & kabuliwala)Iram Anwar
James Matthews' short story “The Park” (1962) takes a closer look at a young black boy's life during the South African Apartheid.
The Kabuliwala Summary | Rabindranath Tagore. “Kabuliwala” by Tagore is a tale of heart-rending friendship between a 5-year-old Bengali girl Minnie and an Afghan moneylender, Abdur Rahman or Rahamat.
Tennis elbow (Rpitative injury of lateral epicondyle)Iram Anwar
Lateral epicondylitis, also known as tennis elbow, is an overuse injury causing pain at the outside of the elbow. It results from repetitive microtrauma to the tendons that connect the forearm muscles to the lateral epicondyle. The pathology involves tendon breakdown and inflammation. Risk factors include repetitive arm motions from activities like tennis, manual labor, or keyboard use. Patients experience pain at the lateral elbow that is worsened by gripping or lifting. Examination finds tenderness over the lateral epicondyle and positive Cozen's, Mill's, and Maudsely's tests. Treatment involves rest, bracing, exercises and other conservative measures, with corticosteroid injection or surgery as potential options
Suspension therapy involves supporting parts of the body in slings and ropes fixed above to increase range of motion and muscle strength. There are three main types of suspension therapy - axial, pendular, and vertical. Axial suspension circulates blood flow and strengthens muscles while allowing large joint movements. Pendular suspension increases muscle strength and endurance. Vertical suspension relaxes the suspended body part and improves range of motion. For the elbow joint, vertical suspension hangs the arm vertically while axial fixation attaches all ropes to a single point above the joint, allowing maximum movement on a flat plane. This functional therapy can be done sitting and helps patients with tasks like feeding and turning pages.
The radial nerve runs down the arm and controls wrist and finger movement. Injury to the radial nerve can occur due to physical trauma, infection, or toxins. Symptoms include numbness, tingling, pain and difficulty bending the wrist or fingers. Treatment depends on the cause but may include medications, injections, physical therapy, braces and sometimes surgery to repair nerve damage or release entrapment.
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This document discusses the management of postoperative complications from surgery. It notes that complications can be general, like fever or infection, or specific to the type of surgery. The likelihood of complications depends on factors like the patient's health and type/extent of surgery. Common complications include cardiovascular issues, infections, delirium, DVT, and more. Prevention involves early mobilization, breathing exercises, nutrition, and wound care. Post-operative management includes pain control, wound monitoring, vital sign checking, mobilization encouragement, and communication with the patient. Depending on the complication, interventions may include antibiotics, medications, blood transfusions, or re-suturing. Close monitoring is important to detect complications early.
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- Kallu is a young boy who works very hard as a laborer for a middle-class Muslim household, doing various chores from morning until night.
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Exploiting Artificial Intelligence for Empowering Researchers and Faculty, In...Dr. Vinod Kumar Kanvaria
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3. ULTRASOUND
• Therapeutic ultrasound is defined by any ultrasonic procedure that utilizes ultrasound
for therapeutic applications. These procedures can include lithotripsy, cancer therapy,
ultrasound hemostasis, HIFU, transdermal ultrasound drug delivery, targeted
ultrasound drug delivery and ultrasound assisted thrombolysis. Ultrasound therapies
include unfocused ultrasound and focused ultrasound (FUS), with the difference being
the rate at which the sound waves penetrate the tissues. These high-frequency sound
waves that measure between 800,000 Hz and 2,000,000 Hz stimulate the tissues
beneath the skin’s surface via an applicator or transducer that stays in constantly
moving direct contact with the patient’s skin.
4. Therapeutic ultrasound offers two types of effects,
• Thermal
• Non-thermal/mechanical
1.THERMAL EFFECT
Thermal effects are characterized by the various absorption of the sound waves, while
non-thermal and mechanical effects come from acoustic streaming, microstreaming and
cavitation. Using a more continuous transmission of sound waves, thermal ultrasound
increases heat and friction in relation to the microscopic vibrations it makes in the deep
tissue molecules. This warming effect enhances healing and repair in the soft tissues
through the increase of metabolism at the cellular level.
5. 2.NON –THERMAL EFFECT
The non-thermal effects of US are now attributed primarily to a combination of
CAVITATION and ACOUSTIC STREAMING There appears to be little by way of
convincing evidence to support the notion of MICROMASSAGE though it does sound
rather appealing. CAVITATION in its simplest sense relates to the formation of gas filled
voids within the tissues & body fluids.
There are 2 types of cavitation - STABLE & UNSTABLE which have very different
effects. STABLE CAVITATION does seem to occur at therapeutic doses of US. This is the
formation & growth of gas bubbles by accumulation of dissolved gas in the medium. They
take apx. 1000 cycles to reach their maximum size. The `cavity' acts to enhance the
acoustic streaming phenomena (see below) & as such would appear to be beneficial.
6. UNSTABLE (TRANSIENT) CAVITATION is the formation of bubbles at the low pressure part of the
US cycle. These bubbles then collapse very quickly releasing a large amount of energy which is
detrimental to tissue viability. There is no evidence at present to suggest that this phenomenon occurs at
therapeutic levels if a good technique is used. There are applications of US that deliberately employ the
unstable cavitation effect (High Intensity Focussed Ultrasound or HIFU) but it is beyond the remit of this
summary.
ACOUSTIC STREAMING is described as a small scale eddying of fluids near a vibrating structure
such as cell membranes & the surface of stable cavitation gas bubble This phenomenon is known to
affect diffusion rates & membrane permeability. Sodium ion permeability is altered resulting in changes
in the cell membrane potential. Calcium ion transport is modified which in turn leads to an alteration in
the enzyme control mechanisms of various metabolic processes, especially concerning protein synthesis
& cellular secretions. The result of the combined effects of stable cavitation and acoustic streaming is
that the cell membrane becomes ‘excited’ (up regulates), thus increasing the activity levels of the whole
cell. The US energy acts as a trigger for this process, but it is the increased cellular activity which is in
effect responsible for the therapeutic benefits of the modality
7. ULTRASOUND ENERGY
Ultrasound (US) is a form of MECHANICAL energy, not electrical energy and therefore
strictly speaking, not really electrotherapy at all but does fall into the Electro Physical
Agents grouping. Mechanical vibration at increasing frequencies is known as sound energy.
The normal human sound range is from 16Hz to something approaching 15-20,000 Hz (in
children and young adults). Beyond this upper limit, the mechanical vibration is known as
ULTRASOUND. The frequencies used in therapy are typically between 1.0 and 3.0 MHz
(1MHz = 1 million cycles per second).
Sound waves are LONGITUDINAL waves consisting of areas of COMPRESSION and
RAREFACTION. Particles of a material, when exposed to a sound wave will oscillate about
a fixed point rather than move with the wave itself. As the energy within the sound wave is
passed to the material, it will cause oscillation of the particles of that material.
8.
9. Clearly any increase in the molecular vibration in the tissue can result in heat generation,
and ultrasound can be used to produce thermal changes in the tissues, though current
usage in therapy does not focus on this phenomenon In addition to thermal changes, the
vibration of the tissues appears to have effects which are generally considered to be non
thermal in nature, though, as with other modalities (e.g. Pulsed Shortwave) there must be
a thermal component however small. As the US wave passes through a material (the
tissues), the energy levels within the wave will diminish as energy is transferred to the
material. The energy absorption and attenuation characteristics of US waves have been
documented for different tissues
10. ULTRASOUND WAVES :
FREQUENCY - the number of times a particle experiences a complete
compression/rarefaction cycle in 1 second. Typically 1 or 3 MHz .
WAVELENGTH -the distance between two equivalent points on the waveform in the
particular medium. In an ‘average tissue’ the wavelength at 1MHz would be 1.5mm and at 3
MHz would be 0.5 mm.
VELOCITY - the velocity at which the wave (disturbance) travels through the medium. In a
saline solution, the velocity of US is approximately 1500 m sec-1 compared with
approximately 350 m sec-1 in air (sound waves can travel more rapidly in a more dense
medium). The velocity of US in most tissues is thought to be similar to that in saline.
11. These three factors are related, but are not constant for all types of tissue. Average figures
are most commonly used to represent the passage of US in the tissues. Typical US
frequencies from therapeutic equipment are 1 and 3 MHz though some machines produce
additional frequencies (e.g. 0.75 and 1.5 MHz) and the ‘Longwave’ ultrasound devices
operate at several 10’s of kHz (typically 40-50,000Hz – a much lower frequency than
‘traditional US’ but still beyond human hearing range.
ULTRASOUND BEAM, NEAR FIELD, FAR FIELD AND BEAM NON
UNIFORMITY
The US beam is not uniform and changes in its nature with distance from the transducer.
The US beam nearest the treatment head is called the NEAR field, the INTERFERENCE
field or the Frenzel zone. The behaviour of the US in this field is far from regular, with
areas of significant interference. The US energy in parts of this field can be many times
greater than the output set on the machine (possibly as much as 12 to 15 times greater).
The size (length) of the near field can be calculated using r2/lambda where r= the radius of
the transducer crystal and lambda = the US wavelength according to the frequency being
used (0.5mm for 3MHz and 1.5mm for 1.0 MHz).
12. As an example, a 'crystal' with a diameter of 25mm operating at 1 MHz will have a near
field/far field boundary at : Boundary = 12.5mm2/1.5mm 10cm thus the near field
(with greatest interference) extends for approximately 10 cm from the treatment head
when using a large treatment head and 1 MHz US. When using higher frequency US, the
boundary distance is even greater. Beyond this boundary lies the Far Field or the
Fraunhofer zone. The US beam in this field is more uniform and gently divergent. The
‘hot spots’ noted in the near field are not significant. For the purposes of therapeutic
applications, the far field is effectively out of reach.
One quality indicator for US applicators (transducers) is a value attributed to the Beam
Nonuniformity Ratio (BNR). This gives an indication of this near field interference. It
describes numerically the ratio of the intensity peaks to the mean intensity. For most
applicators, the BNR would be approximately 4 - 6 (i.e. that the peak Example of an
Ultrasound Beam Plot
13. intensity will be 4 or 6 times greater than the mean intensity). It is considered inappropriate
to use a device with a BNR value of 8.0 or more. Because of the nature of US, the theoretical
best value for the BNR is thought to be around 4.0 though some manufacturers claim to have
overcome this limit and effectively reduced the BNR of their generators to 1.0.
ULTRASOUND BEAM, NEAR FIELD, FAR FIELD AND BEAM NON
UNIFORMITY
• The US beam is not uniform and changes in its nature with distance from the transducer.
The US beam nearest the treatment head is called the NEAR field, the INTERFERENCE
field or the Frenzel zone.
• The behaviour of the US in this field is far from regular, with areas of significant
interference. The US energy in parts of this field can be many times greater than the
output set on the machine (possibly as much as 12 to 15 times greater). The size (length)
of the near field can be calculated using r 2 /lambda where r= the radius of the transducer
crystal and lambda = the US wavelength according to the frequency being used (0.5mm
for 3MHz and 1.5mm for 1.0 MHz).
14. • As an example, a 'crystal' with a diameter of 25mm operating at 1 MHz will have a near
field/far field boundary at : Boundary = 12.5mm2 /1.5mm 10cm thus the near field (with
greatest interference) extends for approximately 10 cm from the treatment head when
using a large treatment head and 1 MHz US.
• When using higher frequency US, the boundary distance is even greater. Beyond this
boundary lies the Far Field or the Fraunhofer zone.
• The US beam in this field is more uniform and gently divergent. The ‘hot spots’ noted in
the near field are not significant. For the purposes of therapeutic applications, the far
field is effectively out of reach.
• One quality indicator for US applicators (transducers) is a value attributed to the Beam
Nonuniformity Ratio (BNR). This gives an indication of this near field interference. It
describes numerically the ratio of the intensity peaks to the mean intensity. For most
applicators, the BNR would be approximately 4 - 6 . intensity will be 4 or 6 times
greater than the mean intensity).
15. ULTRASOUND TRANSMISSION THROUGH THE TISSUES
• All materials (tissues) will present an impedance to the passage of sound waves. The
specific impedance of a tissue will be determined by its density and elasticity.
• In order for the maximal transmission of energy from one medium to another, the
impedance of the two media needs to be as similar as possible.
• Clearly in the case of US passing from the generator to the tissues and then through
the different tissue types, this can not actually be achieved.
• The greater the difference in impedance at a boundary, the greater the reflection that
will occur, and therefore, the smaller the amount of energy that will be transferred.
• It is considered inappropriate to use a device with a BNR value of 8.0 or more.
Because of the nature of US, the theoretical best value for the BNR is thought to be
around 4.0 though some manufacturers claim to have overcome this limit and
effectively reduced the BNR of their generators to 1.0.
16.
17. The difference in impedance is greatest for the steel/air interface which is the first one
that the US has to overcome in order to reach the tissues. To minimise this difference, a
suitable coupling medium has to be utilised.
If even a small air gap exists between the transducer and the skin the proportion of US
that will be reflected approaches 99.998% which means that there will be no effective
transmission.
The coupling media used in this context include water, various oils, creams and gels
Ideally, the coupling medium should be fluid so as to fill all available spaces, relatively
viscous so that it stays in place, have an impedance appropriate to the media it connects,
and should allow transmission of US with minimal absorption, attenuation or
disturbance. The addition of active agents (e.g. anti-inflammatory drugs) to the gel is
widely practiced, but remains incompletely researched.
18. Ultrasound Application - The Critical Angle
In addition to the reflection that occurs at a boundary due to differences in impedance,
there will also be some refraction if the wave does not strike the boundary surface at
90. Essentially, the direction of the US beam through the second medium will not be
the same as its path through the original medium - its pathway is angled. The critical
angle for US at the skin interface appears to be about 15. If the treatment head is at an
angle of 15 or more to the plane of the skin surface, the majority of the US beam will
travel through the dermal tissues (i.e. parallel to the skin surface) rather than penetrate
the tissues as would be expected.
19. The physiological effects of ultrasound are almost identical to those of Pulsed
Shortwave and Laser therapy
PULSED ULTRASOUND Most machines offer the facility for pulsed US output, and
for many clinicians, this is a preferable mode of treatment. Until recently, the pulse
duration (the time during which the machine is on) was almost exclusively 2ms (2
thousandths of a second) with a variable off period.
Some machines now offer a variable on time though whether this is of clinical
significance has yet to be determined. Typical pulse ratios are 1:1 and 1:4 though others
are available (see dose calculations). In 1:1 mode, the machine offers an output for 2ms
followed by 2ms rest. In 1:4 mode, the 2ms output is followed by an 8ms rest period.
The effects of pulsed US are well documented and this type of output is preferable
especially in the treatment of the more acute lesions.
20. THERAPEUTIC ULTRASOUND :
CONTRAINDICATIONS AND PRECAUTIONS CONTRAINDICATIONS :
• Do not expose either the embryo or foetus to therapeutic levels of ultrasound by treating over the uterus
during pregnancy
• Malignancy (history of malignancy is NOT a contraindication – DO NOT treat over tissue that is, or
considered to be malignant)
• Tissues in which bleeding is occurring or could reasonably be expected (usually within 4-6 hours of injury
but may be longer in some instances and for some patients)
• Significant vascular abnormalities including deep vein thrombosis, emboli and severe arteriosclerosis /
atherosclerosis (if increase in local blood flow demanded by the treatment can not reasonably be delivered)
• Patients with Haemophilia not covered by factor replacement
Application over :
o The eye o The stellate ganglion
o The cardiac area in advanced heart disease & where pacemakers in situ
o The gonads o Active epiphyses in children
21. PRECAUTIONS :
• Always use the lowest intensity which produces a therapeutic response
• Ensure that the applicator is moved throughout the treatment (speed and direction not an issue)
• [not necessary with LIPUS applications or the newly advocated STATUS application]
• Ensure that the patient is aware of the nature of the treatment and its expected outcome
• If a thermal dose is intended, ensure that any contraindications that apply have been considered
• Caution is advised in the vicinity of a cardiac pacemaker or other implanted electronic device
• Continuous ultrasound is considered unwise over metal implants
HAZARDS :
Reversible blood cell stasis can occur in small blood vessels if a standing wave is produced while
treating over a reflector such as an air/soft tissue interface, soft tissue/bone or soft tissue/metal
interface whilst using a stationary applicator. This having been said, I can identify no evidence that
this occurs at 'normal' therapeutic levels and with a moving head application method. Treatment
with a stationary treatment head is considered bad practice in the normal therapy environment
(LIPUS excepted).
22. Phonophoresis :
It is the use of ultrasound to penetrate topical medicine deeper below the skin than by
applying it on its own. To be used with pharmacological agents such as anti-inflammatory
steroids and local anesthetics. The sound waves from the ultrasound carry the medication
under the skin to the muscle or tissue to more effectively absorb the medicine. Drugs
requiring specific dosage should not be administered by phonophoresis because it is
difficult to be controlled accurately.
Steps of Use:
1. Apply drug directly to clean skin
2. Apply ultrasound conductive gel over the drug on the skin
3. Ultrasound is turned on and wand is placed over gel/drug content
4. Wand is moved in a circular motion over an area no larger than three (3) times the size
of the wand head
5. This should be done for four (4) to six (6) minutes based on the size of treatment area
6. There should be a warming sensation caused by the use of ultrasound
23. Indications:
Localized inflammation of a tendon
Localized inflammation of a bursa
Localized inflammation of a joint
Contraindications
Do not use over
Genitals
Stomach of a pregnant woman
Epiphyseal plates
Eyes
Open wounds
Pacemakers
Breast implants