Abstract
This paper reviews the current status in using magnetic resonance imaging (MRI) to guide and monitor thermal coagulation of tumours using focused ultrasound. The patient treatment procedure with a second generation phased array system will be described. Several clinical trials have found that patient treatments are feasible and that MRI thermometry allows non-invasive monitoring of clinical treatments. Overall, this emerging modality holds significant potential for non-invasive tumour treatment of both benign and malignant tumours.