title: On-line monitoring of ultrasonic surgery with MR imaging.
abstract: Ultrasonic surgery was performed in rabbits and dogs under the guidance of magnetic resonance (MR) imaging. Two different MR techniques were used to guide the ultrasound beam. T2-weighted images showed lesion formation within a few minutes after sonication. T1-weighted GRASS (gradient-recalled acquisition in the steady state) images were sensitive to temperature elevations, permitting monitoring of lesion creation with MR imaging. Short TR T1-weighted GRASS images were not as helpful in detecting temperature elevation because of a reduction in signal-to-noise ratio. T2-weighted fast spin-echo images were compared with conventional T2-weighted spin-echo images. The former produced high-quality images in a fraction of the imaging time. This study shows that it is possible to monitor and guide ultrasonic surgery with MR imaging.
authors.affiliation: Department of Radiology, University of Arizona Health Sciences Center, Tucson 85724.
authors.forename: A
authors.initials: A
authors.lastname: Darkazanli
authors.forename: K
authors.initials: K
authors.lastname: Hynynen
authors.forename: E C
authors.initials: EC
authors.lastname: Unger
authors.forename: J F
authors.initials: JF
authors.lastname: Schenck
mesh_terms: D000818:Animals; D004285:Dogs; D008279:Magnetic Resonance Imaging; D009132:Muscles / Q000473:pathology / Q000601:surgery*; D011817:Rabbits; D014464:Ultrasonic Therapy / Q000379:methods