Diapositive 1

Some developments: DECT

DECT exploits energy and compositional dependence of



at keV energies



(E) =



(af

compton

(E) + bf

(E))

a and b depend only on composition of material

Scan at 2 energies to give Z

eff

and electron or mass density

via simultaneous equations

Attenuation is function of medium density and elemental composition

Several materials same HU but different densities and elemental compositions