Editing Scanco Administration (section)

===Conversion between Attenuation and Bone Density===
<pre>
BMD_value = mu-value * slope + intercept

mu-value = (BMD_value – intercept) / slope

pixel_Scanco = scaling_factor * (BMD_value – intercept) / slope

</pre>

For example, to convert mu_value of 1.7923 (1/cm) to BMD (mg HA/ccm):
<pre>
BMD_value = 1.7923 * 3.67162994e+02 + -2.06399002e+02 = 451.667 (mg HA/ccm)
</pre>

For example, to convert the lower threshold of 125 mg HA/ccm that is in the IPL script to pixel intensity in Scanco images:
<pre>
pixel_Scanco = 4096 * (125 - -2.06399002e+02) / 3.67162994e+02 = 3697 
</pre>

*You could get the scaling_factor, intercept and slope values from the AIM header of your scan by using aix -l command:
[[File:Aix.JPG|400px]]


*Reference: [[Media:Jbmr.141.pdf|Bouxsein ML, Boyd SK, Christiansen BA, Guldberg RE, Jepsen KJ, Müller R, Guidelines for assessment of bone microstructure in rodents using micro-computed tomography. J Bone Miner Res. 25(7): 1468-86. 2010.]]


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