Cavitation-enhanced MR-guided focused ultrasound ablation of rabbit tumors in vivo using phase shift nanoemulsions.

Advanced tumors are often inoperable due to their size and proximity to critical vascular structures. High intensity focused ultrasound (HIFU) has been developed to non-invasively thermally ablate inoperable solid tumors. However, the clinical feasibility of HIFU ablation therapy has been limited by the long treatment times (on the order of hours) and high acoustic intensities required.

Creating brain lesions with low-intensity focused ultrasound with microbubbles: a rat study at half a megahertz.

Low-intensity focused ultrasound was applied with microbubbles (Definity, Lantheus Medical Imaging, North Billerica, MA, USA; 0.02 mL/kg) to produce brain lesions in 50 rats at 558 kHz. Burst sonications (burst length: 10 ms; pulse repetition frequency: 1 Hz; total exposure: 5 min; acoustic power: 0.

Microbubble contrast agent with focused ultrasound to create brain lesions at low power levels: MR imaging and histologic study in rabbits.

Purpose: To evaluate magnetic resonance (MR) imaging-based thermometry for predicting the onset and spatial extent of lesions produced by focused ultrasound combined with a microbubble contrast agent (Optison; GE Healthcare, Milwaukee, Wis) and to compare the resulting induced temperature increase and threshold for damage with those in studies performed without the agent.

Materials And Methods: The experiments were approved by the animal care committee. Fifty-three locations in the brains of 15 rabbits were sonicated with various exposure parameters by using a 1.