MediSono P25 EXP, User Manual

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1 Safety
6 Basic User Manual
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3 Acoustic Power Principle
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Perform ultrasound procedures prudently under the guidance of the ALARA (as low
as reasonably achievable) principle. Expose the patient to only the lowest practical
transmit power levels in the shortest possible period to achieve a satisfactory
diagnosis.
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Do not continuously scan the same part of a patient or expose the patient to prolonged
scanning. Doing so may harm the patient.
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Do not expose the fetus to prolonged scanning in the Doppler mode.
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Although the output power is automatically controlled for the selected applications,
high TI values should be kept to a minimum or avoided in obstetric applications.
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You should be familiar with the performances and operations of the system, observe
the ultrasound output parameters on the screen all the time.
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1 Biological Safety
Diagnostic ultrasound is recognized as being safe, but the possibility of biological effects
exists when using it in high exposure levels and long exposure times. Thus ultrasound
should be used in a prudent manner to provide medical benefit to the patient.
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2 ALARA
It is required to practice ALARA when using ultrasound energy. Practicing ALARA
ensures that the total energy level is controlled below a low enough level at which
bioeffects are not generated while diagnostic information is being accumulated. The total
energy is controlled by output intensity and total radiation time. The output intensity
necessary for examinations differs depending on the patient and the clinical case.
Not all examinations can be performed with an extremely low level of acoustic energy.
Controlling the acoustic level at an extremely low level leads to low-quality images or
insufficient Doppler signals, adversely affecting the reliability of the diagnosis. However,
increasing the acoustic power more than necessary does not always contribute to an
increase in quality of information required for diagnosis, rather increasing the risk of
generating bioeffects.
The operator must take responsibility for the safety of the patient and utilize the ultrasound
deliberately. Deliberate use of the ultrasound means that output power of the ultrasound
must be selected based on ALARA. Additional information regarding the concept of
ALARA and the possible bioeffects of Ultrasound is available in a document from the
AIUM (American Institute of Ultrasound Medicine) title “Medical Ultrasound Safety”.