Therapeutic ultrasound is what can be used for curative (instead of diagnostic) functions and is ordinarily generated in 1 million cycles per minute or one megacycle (MHz).
Ultrasound was initially explored in Europe and has been introduced into the USA from the early 1950’s, as this moment, using ultrasound has increased, and it remains a remarkably common modality today.
Mechanism of action
The present causes the crystal to flex, first in 1 direction and then another, as the present alternates Titan gel. This deformation of the crystal generates what’s known as piezoelectric energy.
The vibration energy is moved into a metal plate, generally nickel-plated brass, and the individual’s tissue. The crystal and metallic plate are housed from the transducer or solid head of this device.
It’s not transmitted through a vacuum
It’s transmitted badly through gases
It’s transmitted best through gas-free fluids and high-density solids
Comes with an oscillator that generates electromagnetic wave in high frequencies.
Larger transducer surface is much better (7-13cm*), but little enough to keep skin contact.
Waves are emitted at a cylindrical beam vertical to traducer surface. Therefore maintain the transducer head parallel to surface.
Never permit the beam to take into the atmosphere without water or gel since this might damage the crystal.
To test crystalon the mind, turn the intensity up that the water should flow.
Air doesn’t run well, should use a coupling medium. Use a business dyes, not mineral oil and a number of gels will include compounds that could promote healing like, vit E, and aloe.
Since US travels through human tissues, it gradually reduces in strength because of attenuation. Attenuation is the consequence of absorption, reflection and refraction, together with absorption accounting for approximately half of attenuation.
Proteins are the Significant absorbers of US
– Bone reflects waves, which fulfill incoming waves: Dot hence heat generation (periosteal burning off )
– Metal artefacts reflects waves however consume heat therefore warning
Conversion of this mechanical power of US to heating is expressed as a absorption coefficient and can be determined by tissue type and frequency. This coefficient is extracted in decibels/cm and is best for cells with the maximum collagen material and increase in percentage to the US frequency.
Absorption coefficients at decibels/cm at 3 and 1 MHz
The thickness of tissue where the US intensity is half of its first intensity is tissue and frequency type determined
Half depths in mm and 3 MHz
US waves are represented in tissue interfaces using most manifestation occurring where there’s the best gap between the acoustic impedance of adjoining tissues.
There’s 100% manifestation of US in an air-skin port and just a 0.1% manifestation at couple moderate – interface. At the body most manifestation approx 35% happens at gentle tissue-bone interface.
The redirection of a wave with an interface
When refraction happens, the US wave passes the tissue at the same angle and proceeds through the tissue in another angle.
There’s not any certain means of just calculating just how much energy is consumed in any specific tissue, the conclusion about dose is a matter of judgement to some degree.
– Constant output
Constant delivery of US during the treatment period
Employed sub acute and chronic stages
Audio off and on (variable ratio)
I.e. 20 percent or 1:5 duty cycle is on 20 percent of their time off 80 percent of their time: on for 2ms off to 8ms
When ultrasound is delivered in at heart manner, using a 20% duty cycle or reduce the heat generated through the time on is spread throughout the time.
Employed more for intense and sub-acute point where warmth isn’t desirable. Also pulsed US was proven to boost cellular permeability more the continuous US (see below) particularly at 1:5 in an intensity of 0.5-0.75 W/cm.
The intensity implemented should be changed in accord with the character of this lesion (chronic higher than severe ) tissue form (see above) reduced intensities for greater absorbers.
For thermal effects when using a frequency of 1 MHz utilize an intensity of between 1.5 to 2.0 W/cm, in a 3MHz frequency generally an advantage of 0.5 W/cm is adequate as a result of energy being consumed in a smaller superficial volume of tissue.
When wanting to attain thermal effects you anticipate the individual to feel a moderate heating after two to three minutes of therapy, if this doesn’t occur increase the strength.