Physics Athens 2016

Homogeneity

Clinically relevant?

Conformality

Steep dose gradient

Applications

Examples

SIB, multiple GTV/CTVs...

Intentionally inhomogeneous dose distributions

prostate (rectum), head neck (spinal cord), pelvis

Coverage of concave PTV with better sparing of OAR

nasopharyngeal, prostate, head-neck cancer,…

Better coverage of tumors near critical structures (also convex)

spine, head-neck,…

Re-irradiation of locally recurrent tumors

Potential of IMRT

Brachytherapy, protontheray

Compensation of plans

→ delivery of conventional doses with ↓ toxicity → delivery of higher doses without ↑ toxicity

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