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Changes in anatomy over the course of treatment
•
10 H&N – oropharingeal ca pts, IMRT
•
CBCT prospectively acquired weekly,
OARs dose/volume compared to the
planned CT
•
Evaluation of the use of KV CBCT for
dose monitoring and examine if
dosimetric impact of such changes on the
parotid and OARs require replanning
•
Patient weight loss (mean:7.5 kg) and
parotid volume shrinkage was observed,
but no significant excess dose to OAR
•
No need for replanning in this
patient cohort
(Ho
et al
2011)
Fig. 1. Contouring parotid on cone beam
computed tomography (CBCT) (b) using
planning CT (a) as reference
.