MR-guided focused-ultrasound ablation system: determination of precision and accuracy in preparation for clinical trials.

The authors analyzed the accuracy and precision of focal-spot placement with a magnetic resonance-guided, focused-ultrasound system. Average absolute accuracy errors ranged from 0.2 to 1.0 mm, and average absolute individual precision errors ranged from 0.2 to 0.3 mm. To prevent damage to vital structures, single sonications and sonication grids should be placed beyond approximately 2 and 1 mm, respectively.