Scott Hanvey1, John Foster2
1Radiotherapy Physics, Beatson West of
Scotland Cancer Centre, Glasgow, Lanarkshire, United Kingdom; 2MRI
Physics, Beatson West of Scotland Cancer Centre, Glasgow, United Kingdom
Accurate
localisation of the planning target volume (PTV) is vitally important in
radiotherapy. The excellent soft tissue contrast of MRI makes it an ideal
imaging modality for radiotherapy of the head and neck. Registration of MRI with CT can be
problematic since patients are not positioned in the same way. The following
study compared the accuracy of the registration of MRI with CT in 20 head and
neck patients receiving an MRI in the typical curved table and within an
immobilisation device. It also measured the PTVs of patients in the normal
and radiotherapy position in MRI.