Direct Controls; Output Display; Related Guidance Documents - FujiFilm SonoLite M-Turbo Guia Del Usuario

Prudent use of ultrasound requires that patient exposure to ultrasound be limited to the lowest ultrasound
output for the shortest time necessary to achieve acceptable diagnostic results. Decisions that support
prudent use are based on the type of patient, exam type, patient history, ease or difficulty of obtaining
diagnostically useful information, and potential localized heating of the patient due to transducer surface
temperature.
The system has been designed to ensure that temperature at the face of the transducer will not exceed the
limits established in IEC 60601-2-37: Particular requirement for the safety of ultrasound medical diagnostic
and monitoring equipment. See "Transducer surface temperature rise" on page 17. In the event of a
device malfunction, there are redundant controls that limit transducer power. This is accomplished by an
electrical design that limits both power supply current and voltage to the transducer.
The sonographer uses the system controls to adjust image quality and limit ultrasound output. The system
controls are divided into three categories relative to output: controls that directly affect output, controls that
indirectly affect output, and receiver controls.

Direct controls

2
The system does not exceed a spatial peak temporal average intensity (ISPTA) of 720 mW/cm for all
imaging modes. (For either the Ophthalmic or Orbital exam, the acoustic output is limited to the following
2
values: ISPTA does not exceed 50 mW/cm ; TI does not exceed 1.0, and MI does not exceed 0.23.) The
mechanical index (MI) and thermal index (TI) may exceed values greater than 1.0 on some transducers in
some imaging modes. One may monitor the MI and TI values and adjust the controls to reduce these values.
See "Guidelines for reducing MI and TI" on page 9-22. Additionally, one means for meeting the ALARA
principle is to set the MI or TI values to a low index value and then modifying this level until a satisfactory
image or Doppler mode is obtained. For more information on MI and TI, see Medical Ultrasound Safety, AIUM
(a copy is included with each system) and IEC 60601-2-37 Annex "Guidance on the interpretation of TI and
MI to be used to inform the operator."

Output display

Related guidance documents

Information for Manufacturers Seeking Marketing Clearance of Diagnostic Ultrasound Systems and
Transducers, FDA, 2008.
Medical Ultrasound Safety, American Institute of Ultrasound in Medicine (AIUM), 2014. (A copy is included
with each system.)
Acoustic Output Measurement Standard for Diagnostic Ultrasound Equipment, NEMA UD2-2004.
IEC 60601-2-37:2007, Particular requirements for the basic safety and essential performance of ultrasonic
diagnostic and monitoring equipment.
16 Direct controls