Target Volume Determination 2015

ADC and cellularity

Three principal axes: A second look DWI assesses also preferential direction of movement of water molecules

Fiber tracking with Diffusion Tensor Imaging • Diffusion: tractography and fractional anisotropy

Tensor imaging/ tractography Fractional anisotropy

Chenevert et al., J Natl Cancer Inst 2000; 92:2029–36

Fiber tracking

Fractional anisotropy • Degree of preferential movement along one axis – FI = 0: Equal movement in all directions – FI = 1: Movement in one direction only • Measures the degree of architectural disturbance in organized tissues – Tumor infiltration in white matter

Quantifying disorder in fiber arrangement • Diffusion: fractional anisotropy

• Diffusion: tractography

,900

Healthy controls (n=5) pat 1

FA

,000

Possition of the CC genu 1st body 2nd body 3rd body splenium

Stieltjes et al. 2002