IMRT

Rectal bleeding: dose-volume, dose-surface or dose wall?

- Empty rectum: DWH ≈ DVH - Full rectum: DWH ≈ DSH

Robust solutions: Empty the rectum at plan CT scan and use DVH Use DSH for distended rectum (rectal balloon )

Several prospective studies ongoing

Sanchez-Nieto B, Fenwick JF, Nahum A E et al 2001 Biological dose surfacemaps: evaluation of 3D dose data for tubular organs Radiother. Oncol. 61 S52