Dynatron 150plus, Service Manual

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Dynatron ® 150 plus
Ultrasound Usage Cautions
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• Holding the soundhead in one place on the patient’s skin
• Moving the soundhead too slowly
• Treating an area where sensory nerve damage is present with a loss of normal
skin sensation
• Time (Caution: Don’t treat too long).
Bony prominences are especially susceptible, as they reflect sound waves and
increase intensity to the periosteum resulting in a burning sensation. Desensitized
areas can be overheated or burned without the patient realizing it, so extreme care
must be taken with these patients (e.g. diabetes, neural damage, etc.)
Burns can be avoided as long as the treatment causes no pain, tingling, excess heat or
aching (for patients with normal skin sensation). Use sufficient coupling agent and
make sure there are no bubbles in the gel. When treating in water, clear the bubbles
off the soundhead and off the patient’s skin.
An uncalibrated unit can also cause tingling, excess heat, aching, or a burning
sensation.
Output Power
Higher output levels have a greater potential for patient discomfort. Output power
may be reduced by simply choosing a lower watt setting. Output power is also
effectively reduced by selecting a pulsed duty cycle.
Coupling
The term “coupling” refers to the ability to deliver ultrasonic waves from the
soundhead to the skin surface with as little impedance or dissipation of power as
possible. The best coupling is achieved when the soundhead has full, direct contact
over the treatment site or when the treatment site and soundhead are separated only
by a substance that provides excellent conductance.
For example, water is an excellent conductor of ultrasonic waves. Therefore,
Ultrasound treatment in water provides excellent coupling.
Air is a poor conductor of ultrasonic waves. If any part of the soundhead is exposed
to air during the treatment, coupling is decreased. The air bubbles in a whirlpool, for
example, can decrease the effective Ultrasound therapy to the patient.
When treating a patient outside of water, the soundhead must maintain good contact
with the patient’s skin at all times. In addition, a good conductive gel or lotion
should be used to ensure the best possible coupling. Many such products are
commercially available specifically for Ultrasound therapy.