MORGATE BiomédicalMORGATE Biomédical - Testeurs biomedicaux > Fantômes d'Echographie en Mode B
Model 411 thread and low contrast for trans-rectal and trans-urethral transducers
Description and specifications:
The phantom is 12 cm wide, 4 cm high and 11 cm deep.
The scanning surface is covered with a protective plate of 0,5 mm PP that allows transmission of Ultrasound.
The phantom contains:
10 twisted threads for 30-40 dB axial and lateral resolution. The position of each individual thread is correct within +/- 0,4 mm.
3 groups of 11 twisted threads for 6 dB axial and lateral resolution.
3 groups of low contrast cylinders, that deviates +6 dB, +3 dB and -6 dB from the background. The first group is 5 mm in diameter and is centred 2 cm below the surface. The 2 next groups are 10 mm in diameter and are centred 6 cm and 10 cm below the surface.
Attenuation of background material: 0,5 dB * cm * MHz. Tolerance see data sheet.
Sound speed of background material 1540 m/sec. Tolerance see data sheet.
All threads consists of 2 nylon filaments twisted >1 times per mm.
Outer dimensions: 18,5 cm * 18,5 cm * 7 cm
Weight: 1,2 kg
20 dB beam width:
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Optimise the focus of the scanner in the region of test.
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Reduce the amplification, so that the threads just can be seen.
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Increase the amplification 20 dB.
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Measure the dimensions of one wire axial and lateral.
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Repeat step 1 to 4 at relevant depths.
6 dB beam width:
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Optimise the focus of the scanner in the region of test.
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Adjust the amplification, so that the wires are medium grey.
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Notice how many of the wires in the 6 dB group that can be seen.
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Repeat step 1 to 3 at relevant depths.
Maintenance:
Once every Month inspect the phantom.
The surface must always be covered with 1/2 - 1 cm preservative fluid. Fluid that disappears by desiccation should be replaced by distilled water.
Once every 3 month replace the preservative fluid.
Please notice that the lid may not be 100 % tight. Drain fluid off before transportation, but never let it stay dry more than a few days.
The phantom will not stand frost. Safe storage temperature: 0 - 45 degrees Celsius.
Prescription for preservative fluid:
906 ml Distilled Water
94 ml Glycerol (85 %) or 65 g PEG MW400
5 g Acnibio OCS
1 g Citric ascid