title: Sensitivity of effective radiating area measurement for therapeutic ultrasound transducers to variations in hydrophone scanning technique.
abstract: Clinical efficacy and safety may be compromised if output from ultrasonic therapy transducers differs significantly from the indicated value. Space-averaged effective intensities selected for treatment are a ratio of the emitted ultrasonic power to the effective radiating area (ERA). In this study, ERA measurements for 17 commercially available devices were obtained by using a hydrophone scanning technique, and sources of systematic error were assessed by computer simulation. Marginal differences in technique may lead to differences of up to 50% in measured values. Suggestions are made for the improvement of consistency in such measurements.
authors: Bureau of Radiation and Medical Devices, Health and Welfare Canada, Tunney's Pasture, Ottawa, Ontario.
authors: S H
authors: SH
authors: Bly
authors: R G
authors: RG
authors: Hussey
authors: J P
authors: JP
authors: Kingsley
authors: A W
authors: AW
authors: Dickson
mesh_terms: D003198:Computer Simulation; D014159:Transducers; D014464:Ultrasonic Therapy / Q000295:instrumentation* / Q000379:methods; D014465:Ultrasonics