We have investigated an intensity-based image registration technique using a robust correlation coefficient as a similarity measure. The proposed method has an advantage over the ordinary correlation coefficient since it reduces the effect of “outlier” image intensity values. For the application of image registration to radiotherapy or image-guided surgery, there may be outlier samples due to t...

Radiation therapy has come a long way from treatment planning based on orthogonal radiographs with large margins around tumours. Advances in imaging and radiation planning software have led to three-dimensional conformal radiotherapy and, further, to intensity modulated radiotherapy (IMRT). IMRT permits sparing of normal tissues and hence dose-escalation to tumours. IMRT is the current standard...

The delineation of the target volume for irradiation is a critical step in the radiotherapy process. Delivery of radiotherapy occurs over a fractionated course of many treatments. Variations in the position of the target volume may occur on a daily basis during treatment and so the procedure for defining the target volume on a single initial 'snapshot' computed tomography scan has been re-evalu...