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BMD computation. Which Phantom ?

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Mahmoudi Sidi Ahmed

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Apr 27, 2015, 9:25:13 AM4/27/15
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Dear,

I would like to compute the Bone Mineral Density using the calibration that could exploit Phantom values.

My question is. Which Phantom could we use within BoneJ for computing BMD ?

Best regards,

Sidi,

Michael Doube

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Apr 27, 2015, 1:21:57 PM4/27/15
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Dear Sidi,

You should use phantoms that are appropriate to the materials you are
imaging and the technique used to do the imaging. Some clinical CT
systems have phantoms built in under the gantry; at RVC we've used
third-party phantoms placed on the gantry with the specimens. They're
just objects with known attenuation coefficients, which span the range
of attenuation coefficients we're interested in. You make an image of
the phantoms using the same instrument settings as your specimen, then
construct a standard curve by measuring the phantoms' pixel values and
plotting them against phantom attenuation coefficient. This way you
can relate image pixel value to attenuation coefficient. Bear in mind
that X-ray imaging, unless *very* carefully done, contains *lots* of
artefacts that you should be aware of when making your measurements.

Whether or not the measured attenuation coefficient has anything to do
with physical density is another story, however...

Michael
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