Scaling Methods for Registration of Pre- And Post-Androgen Ablation MR Prostate Images

Sophie Riches¹, Mike Partridge², Geoff S. Payne¹, Vonnie A. Morgan¹, Nandita M. deSouza¹

Synposis: MR offers improved visualisation of the prostate gland over the standard CT imaging currently used for planning of radical radiotherapy for prostate cancer. Hormone therapy often prescribed prior to radiotherapy reduces the discrimination of tumor with functional MR techniques therefore necessitating registration of functional information acquired prior to androgen ablation to anatomical images acquired immediately prior to radiotherapy. Comparison of three scaling techniques to account for changes in prostate shape during hormone treatment found assuming bi-linear shrinkage of the prostate allowed pre-treatment tumor regions to be registered to post-treatment anatomical images.