Catheter-based ultrasound devices and MR thermal monitoring for conformal prostate thermal therapy.

Catheter-based ultrasound applicators have been developed for delivering hyperthermia or high-temperature thermal ablation of cancer and benign disease of the prostate. These devices allow for control of heating along the length and angular expanse during therapy delivery. Four types of transurethral applicators were devised for thermal treatment of prostate combined with MR thermal monitoring: sectored tubular transducer devices with directional heating patterns and rotation; planar and curvilinear devices with narrow heating patterns and rotation; and multi-sectored tubular devices capable of dynamic angular control without applicator movement.

Magnetic resonance-guided high-intensity ultrasound ablation of the prostate.

Objectives: This paper describes our work in developing techniques and devices for magnetic resonance (MR)-guided high-intensity ultrasound ablation of the prostate and includes review of relevant literature.

Methods: Catheter-based high-intensity ultrasound applicators, in interstitial and transurethral configurations, were developed to be used under MR guidance. Magnetic resonance thermometry and the relevant characteristics and artifacts were evaluated during in vivo thermal ablation of the prostate in 10 animals.

Multiplanar MR temperature-sensitive imaging of cerebral thermal treatment using interstitial ultrasound applicators in a canine model.

Purpose: To study the feasibility of an interleaved gradient-echo, echo-planar imaging (iGE-EPI) sequence for multiplanar magnetic resonance temperature imaging (MRTI) to monitor intracerebral thermal treatment three-dimensionally using multielement ultrasound applicators.

Materials And Methods: Transmissible venereal tumor (TVT) fragments were injected into the right cerebral hemisphere of five dogs. Guided by MRI, an interstitial ultrasound applicator was inserted into the tumor or normal brain tissue.