Dose Course 2018_Flipping book

How accurate are CT numbers…?

• HU of homogeneous material can vary by 1-2% • Depends on location (beam hardening) – up to 3% • Variation across scanners for high density (>5% in cases) • Electron Density of Tissue Substitutes • Tissue substitutes=tissues?

M. Schwarz

• Tissue Assignment (ICRU and ICRP)?