title: Method for determining the SATA and SAPA intensities for real-time ultrasonographic scanning modes.
abstract: Determination of a complete set of sonographic exposure parameters is desirable for any clinical ultrasound unit and is particularly important in controlled studies of biologic effects. When the exposure system is a diagnostic real-time scanner operating in autoscan mode, the determination of two of these parameters, the spatial average-temporal average (SATA) and the spatial average-pulse average (SAPA) intensities, is not straightforward because of the spatial overlap of successive propagating pulses. A method is described for determining these intensities for autoscan operation. The primary tool in the method is a digital oscilloscope, which supports pretrigger recording and configuring of the oscilloscope's memory into segments that can record rapidly occurring successive pulses, each segment recording one pulse. Results for a few commercially available real-time scanning systems are presented.
authors.affiliation: Department of Medical Physics, University of Wisconsin, Madison.
authors.forename: M C
authors.initials: MC
authors.lastname: Macdonald
authors.forename: E L
authors.initials: EL
authors.lastname: Madsen
mesh_terms: D014465:Ultrasonics; D014463:Ultrasonography / Q000295:instrumentation / Q000379:methods* / Q000706:statistics & numerical data