User's Manual
Vave Personal Ultrasound • USER MANUAL
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CONFIDENTIAL & PROPRIETARY. CAUTION — Investigational device. Limited by Federal law to investigational use. Not commercially available in the US.
• Controls Aecting Display Indices
Use system controls to change the TI and MI values.
B-Mode Controls
• Focus: When the focal depth is near the natural focus of the scanner, the MI may be higher.
• Zoom: Increasing the zoom magnification by spreading the display may increase frame rate, thereby increasing
the TI. The number of focal zones may also increase automatically to improve resolution.
This action may change the MI, because the peak MI can occur at a dierent depth.
Other Control Eects
• B-Mode Depth: An increase in two-dimensional depth will automatically decrease the B-Mode frame rate,
thereby decreasing the TI. The system may also automatically choose a deeper two-dimensional focal depth.
A change of focal depth may change the MI.
• Application: Acoustic output defaults are set when you select an application. Factory defaults vary by application.
Default settings have been chosen below the FDA limits for intended use.
• Imaging Mode Controls: When a new imaging mode is selected, both the TI and MI may change to default
settings. Each mode has a corresponding pulse repetition frequency and maximum intensity point. In combined
or simultaneous modes, the TI is the sum of the contribution from the modes enabled, and the displayed MI is
the largest of the MI values associated with each mode and focal zone enabled. The system will return to the
previously selected settings if a mode is turned o and then reselected.
• Scanner: Each scanner type has unique specifications for contact area, beam shape, and center frequency.
Selecting a scanner initializes its default settings, which varies by scanner, application, and selected mode. These
defaults are set below the FDA limits for intended use.
Step-by-step example of reducing output:
When preparing to do a liver scan, the first step is to select the appropriate preset. Then adjust the focus to the
area of interest and increase the receiver gain to produce a uniform representation of the tissue.
Acoustics
The system limits patient contact temperature to 43°C (109°F), and acoustic output values to their respective U.S.
Food and Drug Administration limits. A power-protection circuit protects against over-current conditions. If the
power monitor protection circuit senses an over-current condition, then the drive voltage to the scanner is shut o
immediately, preventing overheating of the scanner surface and limiting acoustic output. Validation of the power
protection circuit is done under normal system operation.
A temperature elevation of less than 1.5°C (2.7°F) is considered harmless to human tissue (including embryo or
fetus). Temperatures in excess of this may cause harm, depending on the length of time maintained. A temperature
elevation of 4°C (7.2°F), maintained for five minutes or more, is considered to be potentially hazardous to a fetus
or embryo.
• Acoustic Output & Measurement
The acoustic output for this system has been measured and calculated in accordance with the IEC 60601-2-37,
“Medical electrical equipment — Part 2-37: Particular requirements for the basic safety and essential performance
of ultrasonic medical diagnostic and monitoring equipment,” Edition 2.1, 2015-06; the NEMA Standard Publication
UD-2, “Acoustic Output Measurement Standard for Diagnostic Ultrasound Equipment,” Revision 3, 2004; the IEC
62359, “Test methods for the determination of thermal and mechanical indices related to medical diagnostic
ultrasonic fields,” Edition 2.0, 2017-09; and the FDA guidance document “Information for Manufacturers Seeking
Marketing Clearance of Diagnostic Ultrasound Systems and Scanners,” September 2008.