Transcript Ultrasound Dose Calculations

Practical and Methods of US
Application
Dr. Mohammed TA, Omar
Methods of Application
Ultrasound therapy is normally applied using one of three
basic methods of application
A- Direct contact.
B- Water immersion.
C- Water bag application (Bladder application ).
D- Combined therapy
E- Phonophoresis
Principles of US Application
1) Use ultrasound only if adequately trained to do so
2) Use ultrasound to treat only those patients with conditions
known to respond favorably to this treatment (indications)
3) Check the ultrasonic output from the machine by placing
the head just below the water surface in a suitable
container and observing the disturbance appears in water.
4) Move the applicator constantly throughout the treatment,
to avoid the damaging effects of standing waves. The
movement of the head must be slow enough to allow the
tissue to deform , and fast enough to prevent “hot spots”.
Principles of US Application
5) Apply the coupling to the skin surface and/or the treatment
head, and put it on the skin before the machine is turned on
to avoid damage of head transducer.
7) Inspect the skin surface will be treated.
8) Explain the treatment to the patient and set up the
treatment parameters.
9) If the patient feels any additional pain during treatment,
either reduce the intensity to a pain-free level.
Principles of US Application
10) Duration of treatment
1. The minimum treatment times are 3minutes/area
2. The maximum 10minutes/area
3.
The average would be in the region of 5-7minutes.
11) Progression and frequency of treatment
1.
2.
Recent & acute conditions should be treated once or twice daily
Chronic conditions may be treated on alternating days.
Progression is based on the outcome of the previous
treatment.
1.
2.
If there is objective and subjective improvements the
treatment should be continued at the same dose.
If the symptoms are worse the treatment should be reduced or
discontinued.
A- Direct contact
1.
This method is suitable for flat body areas or regular
surface as it allows easy constant parallel contact of
sound head to the skin surface.
2.
When using the direct technique, the ultrasound head is
put against the skin with only a thin layer of couplant
(gel or lotion) in between.
The pattern of movement can be a series of
1-Overlapping circle,
2-Concentric circle
3-Figure of eight
4-transverse stroke
This techniques is suitable for area up to three times
the size of the treatment head.
3.
4.
A- Direct contact
Application Procedure:
Step 1: Apply a generous amount of coupling medium to clean
dry skin
Step 2: Move transducer as described in (3)
Step 3: Turn intensity up to treatment level
Step 4: Each circle / stroke should overlap the previous by ½
Step 5: Treatment area limited to 3 times size of transducer
Step6: Moving the sound head approximately 4 cm per second)
Step 7: Transducer must stay in contact and in motion to avoid
overheating of the transducer and damage to the crystal
Indirect contact : 1-Water Immersion
1- US is easily transmitted through water so that little
energy is lost. Treatment by this method is valuable
because very irregular surfaces and tender areas can be
comfortably treated as the treatment head does not exert
pressure on the skin.
2- The treatment head is placed in water and moved parallel
to the surface of the treated part and held 1-2cm a part .
3- It is preferable to use degassed water to avoid bubbles
formation
Indirect contact : 1-Water Immersion
Immersion Application Procedure:
Step 1: Submerge part fully in tub of water (plastic, ceramic,
rubber, or fiberglass).
Step 2: Submerged ultrasound head and hold approximately 0.5
to 2 cm from the skin surface (intensity should be increased
possibly as much as 50% to ensure effectiveness).
Step 3: Move ultrasound head slowly over treatment area (if air
bubbles accumulate on the sound head or treatment area,
they may be wiped away quickly).
Step 4: Turn intensity up to treatment setting
Indirect contact : 2-Water bag application
Bladder Application
1-Used for the irregular surfaces that cannot be placed in
water bath.
2-The plastic or rubber bag filled with water, forming
water cushion between the treatment head and skin.
3-The bag is filled with warm water or degassed water.
4-The treatment head and the side of the bag in contact
with the skin are covered with coupling agent.
5-The treatment head is moved by deforming the bag or by
moving over the surface of the bag.
Indirect contact : 2-Water bag application
Bladder Application
Bladder Application Procedure:
Step 1: Fill balloon with water
Step 2: Coat both sides of the balloon with coupling medium
Step 3: Place balloon over treatment area
Step 4: Place transducer over balloon
Step 5: Increase power to desired intensity
Step 6: Balloon and water will disperse and transmit sound
waves to the underlying tissue
D-Combination Therapy
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Ultrasound can be used with a variety of modalities to
accomplish a series of treatment goals
– Use of hot packs with ultrasound may have an additive effect on
muscle temperature.
– Cold packs, while often used in conjunction with ultrasound, may
interfere with heating (do not apply before US).
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With electrical stimulation, it is often useful for trigger
point treatment (blood flow, muscle contraction and pain
modulation
E-Phonophoresis
Phono means sound
Phoresis means migration of ions through membrane by action
of an electrical current.
Phonophoresis is defined as the movement of the drugs
through skin into subcutaneous tissues under influence of
ultrasound.
Phonophoresis will be dependent on
1. frequency
2. intensity
3. duty cycle
4. treatment duration
5. nature of the drug molecule
In phonophoresis:
Ultrasound facilitates the passage of some drugs into
and through the skin
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The effects are due both to absorption of the drug and
to the ultrasound.
Lower ultrasonic frequencies appear to lead to deeper
drug penetration.
Pulsing ultrasound may lead to better drug penetration.
The quality of drug entering the skin is proportional, in
general, to the time and intensity of ultrasound
application
E-Drugs Used in Phonophoresis
Anti-inflammatory’s
– Cortisol
– Dexamethasone
– Salicylates
Analgesics
– Lidocaine
Drugs promoting wound healing
Drugs affecting the circulation.
Termination of the Treatment
Reduce the intensity (switch )before removing the
transducer
 Clean the remaining gel from the patient’s skin
and sound head
 To ensure continuity of treatment sessions:
– Record the treatment parameters
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Output frequency
Intensity
Duration
Duty cycle
Immediately initiate any post-treatment stretching
Possible Dangers of US
1-Burns could occur if the heat generated
exceeded the physiological ability to dissipate it.
2-Tissue destruction would result from transient
cavitations.
3-Blood cell stasis and endothelial damage may
occur if there is standing wave formation.
All of them rarely occurred