ATS 535-H, Руководство пользователя

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INTRODUCTION
Quality assurance tissue-mimicking phantoms are used to evaluate the accuracy and performance of ultrasound
imaging systems. The phantoms mimic the acoustic properties of human tissue and provide test structures within
the simulated environment. They are essential to detect the performance changes that occur through normal
aging and deterioration of system components. Routine equipment performance monitoring can reduce the
number of repeat examinations, the duration of examinations and maintenance time.
This phantom is constructed of a new rubber-based tissue-mimicking material developed by ATS Laboratories.
This material extends the useful life of the phantom by avoiding problems due to melting, freezing, dehydration
and breakage from dropping which are common with hydrogel (water-based) phantoms. By eliminating these
problems, the durability, quality and reliability of this product is guaranteed for three years.
The acoustic properties of all biologic and non-biologic materials are affected by temperature variations. Most
diagnostic imaging systems and tissue-mimicking phantoms are calibrated at room temperature, commonly
referred to as 23°C. To ensure measurement accuracy ATS incorporates a thermometer strip affixed to the outside
surface of the phantom housing.
The sound velocity of most diagnostic imaging systems is calibrated to 1,540 meters per second (mps), the
assumed average velocity of sound through human soft tissue. The rubber-based tissue-mimicking material has a
sound velocity of 1450 mps at 0.5dB/cm/Mhz at room temperature (23°C). The line targets and anechoic target
structures have been physically positioned to compensate for the differences in the speed of sound, assuring
accuracy of measurements.
PRODUCT DESCRIPTION
The Model 535-H rubber-based, tissue-mimicking (TM) phantom is designed to fulfill the basic testing
requirements of a Quality Assurance Program.
The phantom is designed with a combination of monofilament line targets and six tissue mimicking cylindrical
targets of varying sizes. The monofilament line targets have a diameter of 0.12 mm, to optimize the displayed
image at frequencies ranging from 2.25 to 7.5 MHz. Four groups of line targets are provided to evaluate the
vertical and horizontal calibration measurements, axial-lateral resolution and the dead zone.
TESTS PERFORMED
· Dead Zone or Transducer Ring-Down
· Vertical Measurement Calibration
· Horizontal Measurement Calibration
· Focal Zone
· Sensitivity
· Axial & Lateral Resolution
· Functional Resolution, Definition and Fill-In