Mettler Electronics Sonicator 740, Инструкция по эксплуатации

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Mettler Electronics Corp. — Rev.G_06/28/12
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By keeping these considerations in mind as well as the size of the area to be treated, selection of the proper
sized applicator can be made. In general the larger 10 cm² applicator should be used to treat large areas.
Remember to always check the labeling for the effective radiating area of the applicator when selecting
treatment intensities. Some applicator treatment surfaces may appear larger than their actual effective
radiating area.
7.3 Continuous and Pulsed Waves
Ultrasound may be applied in either continuous or pulsed waveform. Advocates of pulsed beam
applications suggest the approach reduces the thermal effects while accenting the mechanical. Wulff in his
paper titled
“ Reduction of Thermic Effect of Ultrasound Dosages by the Use of Pulsed Ultrasound Energy”,
reported, “ .... the use of pulsed ultrasound energy permits accurately controlled reduction of total
ultrasound intensities employed in therapy.” He recommended the use of rectangular pulses and stated,
“The biologic response reactions of the sonated tissue seem to continue during the sound free intervals
provided that a ratio between pulse duration and free interval of 1:4 is maintained.” Laboratory research
being conducted by Dyson and associates in England seems to indicate beneficial non–thermal effects of
ultrasound. However, clinical studies have not been conducted to thoroughly corroborate this evidence.
The Sonicator 740 provides both continuous and pulse wave capabilities. The continuous mode is on more
than 95% of the time and has an unmodulated wave. The pulse settings have pulse frequencies of 100 Hz
with pulse widths of 1, 2 or 5 milliseconds and 9, 8 or 5 milliseconds between pulses. On time to total time is
1:10, 1:5 or 1:2. The duty cycles are 10%, 20% or 50% and the on time to off time ratio for the 20% duty cycle
is 1:4. In the pulse mode, peak power is displayed.