title: MRI-guided focused ultrasound surgery in the brain: tests in a primate model.
abstract: MRI-guided focused ultrasound was tested in the brains of rhesus monkeys. Locations up to 4.8 cm deep were targeted. Focal heating was observed in all cases with MRI-derived temperature imaging. Subthreshold heating was observed at the focus when the ultrasound beam was targeted with low power sonications, and in the ultrasound beam path during high-power exposures. Lethal temperature values and histologically confirmed tissue damage were confined to the focal zone (e.g., not in the ultrasound beam path), except when the focus was close to the bone. In that case, damage to the neighboring brain tissue was observed. Focal lesions were observed on histological examination and, in some cases, in MR images acquired immediately after the ultrasound exposures. The capabilities demonstrated in this study will be of benefit for clinical ultrasound therapies in the brain.
authors.affiliation: Department of Radiology, Harvard Medical School and Brigham and Women's Hospital, Boston, Massachusetts, USA. njm@bwh.harvard.edu
authors.forename: Nathan
authors.initials: N
authors.lastname: McDannold
authors.forename: Mark
authors.initials: M
authors.lastname: Moss
authors.forename: Ron
authors.initials: R
authors.lastname: Killiany
authors.forename: Douglas L
authors.initials: DL
authors.lastname: Rosene
authors.forename: Randy L
authors.initials: RL
authors.lastname: King
authors.forename: Ferenc A
authors.initials: FA
authors.lastname: Jolesz
authors.forename: Kullervo
authors.initials: K
authors.lastname: Hynynen
mesh_terms: D000818:Animals; D001921:Brain / Q000473:pathology / Q000601:surgery*; D008253:Macaca mulatta; D008279:Magnetic Resonance Imaging; D019635:Neurosurgical Procedures / Q000379:methods; D013696:Temperature; D014464:Ultrasonic Therapy