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Dual-energy x-ray CT material extr
action
• CT images are represented by HU = 1000x(
μ
/
μ
w
-1)
–
μ and μ
w
are the linear attenuation coefficients of a material
and of water
• dual-energy material extraction (DECT) is based on
– Taking CT images at two tube voltages (e.g. 100 kVp and 140
kVp)
– The farther apart the energy the better!
– Parameterization of the linear attenuation coefficient results in
ρ
e
and
Z
maps