Poster — Thur Eve — 50: Preliminary Evaluation of Ultrasound Treatment of the Human Prostate Gland Using MRI Thermometry In Vivo

Abstract

Current radical treatments for prostate cancer can have numerous, permanent side effects including incontinence, sexual dysfunction and bowel dysfunction. The development of an effective, minimally invasive treatment with fewer side effects would enhance treatment options, particularly for younger men with low‐risk disease. MRI‐guided transurethral high intensity ultrasound therapy has been shown to have a high degree of accuracy in coagulating tissue. A real‐time feedback system in conjunction with continuous MR thermometry gives the system control over heat deposition, as demonstrated in both gel and preclincal animal models. A subvolume treatment of the gland was performed on six men with low grade prostate cancer who volunteered for the procedure prior to their scheduled radical prostatectomy. Histological measurements were performed on the surgically removed prostate to asses the accuracy of the ultrasound therapy. A spinal anaesthetic was given to the patient to limit discomfort and movement during treatment. A transurethral device fitted with four 5‐mm planar transducers operating at 8MHz delivered the treatment in a 1.5T clinical MRI system. A volume within the prostate was targeted, based on MR images, usually involving a 180° rotation of the device. Temperature uncertainty of ∼1C° was obtained and the coagulation boundary from histology agreed with the target boundary with an accuracy of 1mm ± 1.5mm. This presentation describes a preliminary study of safety and feasibility in human beings.