Radiotherapy treatment planning of brain tumours using MRI alone.

MRI of the brain can provide images of very high quality revealing detailed information especially concerning the extent of abnormalities. As such MRI has great potential in the radiotherapy (RT) planning of brain tumours. However MRI has rarely been used alone as the basis for treatment planning primarily due to concern over potential geometric distortions. Treatment planning using MRI has therefore usually been carried out in conjunction with CT images. This work demonstrates that geometric distortions can be minimized by using a relatively small field-of-view, an increased receiver bandwidth, and a fast spin echo acquisition sequence, and that it is thus possible to perform RT planning using MRI.