ultrasound therapy Flashcards
what is the frequency of US therapy
20,000hz
type of waves in US
ongitudinal mechanical waves that propagate in an electric medium w/ vibration of particles
w/ rarefaction and compression
how is ultrasound therapeutic
Particles in the material conducting the sound oscillate at a fixed point
The oscillation creates heat and produces thermal energy w/in tissues Thermal energy heats cell membranes consequently improving transportation across the cell
how is ultrasound wave generated
transducer contains piezoelectric crystals
Sound waves hit the crystals causing their oscillation
The oscillator generates an alternating current
Therefore electrical energy is created by mechanical energy
Application of an alternating electric current on the piezoelectric crystal generates ultrasound waves
There for alternating electrical energy creates very high frequency vibrational energy
what happens in the cell when US is applied to the skin
rarefaction : small bubbles form
Compression: small bubbles collapse and release thermal energy Thermal energy heats cell membranes consequently improving transportation acros sthe cell
list the therapeutic effects of US
fibrinolytic effect: rx hypertrophic scarring Tixotropic effect(apparently the same thing?) liquifies gell sltn- usful for disc herniation
dose of US soundwaves
1mhz: deep effect
3mhz: superficial effect
what is US measured in
WATTcm-2. Increasing the watt increases analgesia. Decreasing it increases irritation
what is phonophoresis
use of ultrasound to enhance the delivery of topically applied drugs. Phonophoresis has been used in an effort to enhance the absorption of topically applied analgesics and anti-inflammatory agents through the therapeutic application of ultrasound.
what drugs are applied w/ ionophoresis
nsaids and fibrinolytics
contraindications
Epiphysis of growing bones
Directly above a bone
Brain
Internal organs
