Philips Lumify - ALARA Education Program

Biological Safety Safety
Lumify Ultrasound System 37
Philips Healthcare 4535 618 58571_A/795 * MAY 2016
NOTE
The transducers described in this document do not contain natural rubber latex that contacts
humans. Natural rubber latex is not used on any Philips ultrasound transducer.
ALARA Education Program
The guiding principle 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 to 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 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, an 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 in the applications of that technology, have resulted
in the need for more and better information to guide the user. The output display 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 index values, 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 it is controlled by the
user. The ability to limit the index values over time supports the ALARA principle.
Applying ALARA
The system imaging mode used depends upon the information needed. 2D imaging provides
anatomical information, while Color imaging provides information about blood flow.
Understanding the nature of the imaging mode being used allows the sonographer to apply the