Dynatron 150plus, Руководство по обслуживанию

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Dynatron ® 150 plus
Ultrasound Usage Cautions
19
Ultrasound General Information
and Usage Cautions
Ultrasound, by its very nature, has the ability to irritate the patient’s skin. While the
benefits of Ultrasound far outweigh any disadvantages, certain precautions should be
observed to assure maximum safety and comfort for your patients.
A patient’s tendency to have adverse reactions to Ultrasound is dependent upon
several factors. Some of these factors are discussed below. In addition to cautions
listed below, read the contraindications, warnings, and other precautions in this
manual.
Selecting the Appropriate Soundhead
The selection of the appropriate soundhead is based on the size of the area to be
treated. Ultrasound treatments should be kept specific to the tissue involved in
pathology. A good guideline is 2 to 4 times the size of the soundhead. For example:
• A 2 cm
2
soundhead can deliver up to 4 Watts and is appropriate for small areas
(i.e. hands, fingers, feet).
• A 5 cm
2
soundhead can deliver up to 10 Watts and is appropriate for medium
sized areas (i.e. extremities such as arms, legs and cervical areas).
• A 10 cm
2
soundhead can deliver up to 20 Watts and is appropriate for large areas
(i.e. torso and back).
Ultrasound is a directed beam of energy. Therefore, not only will the average spatial
intensity be a factor in the dosage the patient receives, but the time delivered and area
covered will matter as well. For example, an area of 50 cm
2
is treated for 5 minutes.
Then an area of 200 cm
2
is treated for 5 minutes. Both receive the same intensity.
The 200 cm
2
area however does not receive the same dosage (only ¼ ) because as the
soundhead is moved around the area it has to cover represents 4 times as much tissue.
The Soundhead area measurement is the ERA (effective radiating area).
Each
soundhead has an effective radiating area. It is not necessarily the outside diameter of
the soundhead, but the area of the crystal inside, therefore special care should be
taken in selecting the correct size soundhead for the area to be treated according to
the diameter of the crystal. See the Head and Crystal Size Comparison graphic on the
following page.