1 - 20 SONOACE X6 Operation Manual
Biological Safety
For more safety information on probes and biopsy, please refer to Chapter 8 'Probes.'
WARNING
■ Ultrasound waves may have damaging effects on cells and, therefore,
may be harmful to the patient. If there is no medical benefit, minimize the
exposure time and maintain the ultrasound wave output level at low.
Please refer to the ALARA principle.
■ Do not use the system if an error message appears on the video display
indicating that a hazardous condition exists. Note the error code, turn off
the power to the system, and call your local MEDISON Customer Service
Department.
■ Do not use a system that exhibits erratic or inconsistent updating.
Discontinuities in the scanning sequence are indicative of a hardware
failure that should be corrected before use.
■ The system limits the maximum contact temperature to 43 degree
Celsius, and the ultrasonic waves outpu
regulations.
ALARA Principle
Guidance for the use of diagnostic ultrasound is defined by the “as low as reasonably achievable”
(ALARA) principle. The decision as to what is reasonable has been left to the judgment and insight of
qualified personnel. No set of rules can be formulated that would be sufficiently complete to dictate the
correct response for every circumstance. By keeping ultrasound exposure as low as possible, while
obtaining diagnostic images, users can minimize ultrasonic bioeffects.
Since the threshold for diagnostic ultrasound bioeffects is undetermined, it is the sonographer’s
responsibility to control the total energy transmitted into the patient. The sonographer must reconcile
exposure time with diagnostic image quality. To ensure diagnostic image quality and limit exposure time,
the ultrasound system provides controls that can be manipulated during the exam to optimize the results
of the exam.
The ability of the user to abide by the ALARA principle is important. Advances in diagnostic ultrasound not
only in the technology but also in the applications of the technology, have resulted in the need for more
and better information to guide the user. The output indices are designed to provide that important
information
There are a number of variables, which affect the way in which the output display indices can be used to
implement the ALARA principle. These variables include mass, body size, location of the bone relative to
the focal point, attenuation in the body, and ultrasound exposure time. Exposure time is an especially
useful variable, because the user controls it. The ability to limit the index values over time support the
ALARA principle.