Q9 Digital Color Doppler Ultrasound System
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Understand the meaning of the TI, TIS, TIB, TIC and MI output display, as well as the relationship between
these parameters and the thermal/cavitation bioeffect to the tissue.
Expose the patient to only the very lowest practical transmit power levels for the shortest possible time to
achieve a satisfactory diagnosis (ALARA - As Low As Reasonably Achievable).
2.6.1
Safe Scanning Guidelines
Ultrasound should only be used for medical diagnosis and only by trained medical personnel.
Diagnostic ultrasound procedures should be done only by personnel fully trained in the use of the equipment,
in the interpretation of the results and images, and in the safe use of ultrasound (including education as to
potential hazards to the patient and the operator).
Operators should understand the likely influence of the machine controls, the operating mode (e.g. B-mode,
color Doppler imaging or spectral Doppler) and probe frequency on thermal and cavitations hazards.
Select a low setting for each new patient. Output should only be increased during the examination if
penetration is still required to achieve a satisfactory result, and after the Gain control has been adjusted to its
maximum value.
Maintain the shortest examination time necessary to produce a useful diagnostic result.
Do not hold the probe in a fixed position for any longer than is necessary. It should be removed from the
patient whenever there is no need for real-time imaging or spectral Doppler acquisition. The frozen frame
and Cine loop capabilities allow images to be reviewed and discussed without exposing the patient to
continuous scanning.
Do not use endo-cavitary probes if there is noticeable self heating of the probe when operating in the air.
Although applicable to any probe, take particular care during trans-vaginal exams during the first eight weeks
of gestation.
Take particular care to reduce output and minimize exposure time of an embryo or fetus when the temperature
of the mother is already elevated.
Take particular care to reduce the risk of thermal hazard during diagnostic ultrasound when exposing: an
embryo less than eight weeks after gestation; or the head, brain or spine of any fetus or neonate.
Operators should continually monitor the on-screen thermal index (TI) and mechanical index (MI) values
and use control settings that keep these settings as low as possible while still achieving diagnostically useful