title: Effects of varying duty cycle and pulse width on high-intensity focused ultrasound (HIFU)-induced transcranial thrombolysis.
abstract: The goal was to test the effects of various combinations of pulse widths (PW) and duty cycles (DC) on high-intensity focused ultrasound (HIFU)-induced sonothrombolysis efficacy using an in vitro flow model. An ExAblate™ 4000 HIFU headsystem (InSightec, Inc., Israel) was used. Artificial blood clots were placed into test tubes inside a human calvarium and exposed to pulsatile flow. Four different duty cycles were tested against four different pulse widths. For all study groups, an increase in thrombolysis efficacy could be seen in association with increasing DC and/or PW (p < 0.0001). Using transcranial HIFU, significant thrombolysis can be achieved within seconds and without the use of lytic drugs in vitro. Longer duty cycles in combination with longer pulse widths seem to have the highest potential to optimize clot lysis efficacy.
authors.affiliation: Brain Ultrasound Research Laboratory (BURL), Department of Radiology, University of California San Diego, San Diego, CA, 92103, USA ; Department of Neurosciences, University of California San Diego, 200 West Arbor Drive, San Diego, CA, 92103-8756, USA.
authors.forename: Thilo
authors.initials: T
authors.lastname: Hölscher
authors.affiliation: Division of Biostatistics and Bioinformatics, University of California San Diego, San Diego, CA, 92093, USA.
authors.forename: Rema
authors.initials: R
authors.lastname: Raman
authors.affiliation: Brain Ultrasound Research Laboratory (BURL), Department of Radiology, University of California San Diego, San Diego, CA, 92103, USA.
authors.forename: David J
authors.initials: DJ
authors.lastname: Fisher
authors.affiliation: Brain Ultrasound Research Laboratory (BURL), Department of Radiology, University of California San Diego, San Diego, CA, 92103, USA.
authors.forename: Golnaz
authors.initials: G
authors.lastname: Ahadi
authors.affiliation: InSightec, Ltd, 5 Nahum Heth St., Tirat Carmel, 39120, Israel.
authors.forename: Eyal
authors.initials: E
authors.lastname: Zadicario
authors.affiliation: Brain Ultrasound Research Laboratory (BURL), Department of Radiology, University of California San Diego, San Diego, CA, 92103, USA.
authors.forename: Arne
authors.initials: A
authors.lastname: Voie
keywords: Duty cycle; High-intensity focused ultrasound; Pulse width; Stroke; Thrombolysis; Transcranial