Dosimetric verification of biologically adapted IMRT.

Purpose: To investigate the delivery of biologically adapted high resolution intensity modulated radiotherapy (IMRT) to an anthropomorphic phantom, using dosimetric and radiobiologic measures.

Methods: A compartment based 3D hypoxia map of a highly heterogeneous tumor was imported into the CT planning basis of an anthropomorphic phantom. Biologically adapted IMRT was planned according to the corresponding 3D dose prescription map with elevated dose to the hypoxic regions.

Influence of MLC leaf width on biologically adapted IMRT plans.

Introduction: High resolution beam delivery may be required for optimal biology-guided adaptive therapy. In this work, we have studied the influence of multi leaf collimator (MLC) leaf widths on the treatment outcome following adapted IMRT of a hypoxic tumour.

Material And Methods: Dynamic contrast enhanced MR images of a dog with a spontaneous tumour in the nasal region were used to create a tentative hypoxia map following a previously published procedure.

Feasibility of contrast-enhanced cone-beam CT for target localization and treatment monitoring.

A dog with a spontaneous maxillary tumour was given 40 Gy of fractionated radiotherapy. At five out of 10 fractions cone-beam CT (CBCT) imaging before and after administration of an iodinated contrast agent were performed. Contrast enhancement maps were overlaid on the pre-contrast CBCT images.