JUM
HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS
QUICK SEARCH:   [advanced]


     

This Article
Right arrow Full Text
Right arrow Full Text (PDF)
Right arrow Alert me when this article is cited
Right arrow Alert me if a correction is posted
Services
Right arrow Similar articles in this journal
Right arrow Similar articles in PubMed
Right arrow Alert me to new issues of the journal
Right arrow Download to citation manager
Right arrow reprints & permissions
Citing Articles
Right arrow Citing Articles via Google Scholar
Google Scholar
Right arrow Articles by Hirokawa, T.
Right arrow Articles by Burns, P. N.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Hirokawa, T.
Right arrow Articles by Burns, P. N.
© 2007 by the American Institute of Ultrasound in Medicine
J Ultrasound Med 26:731-738 • 0278-4297

Insonation of the Eye in the Presence of Microbubbles

Preliminary Study of the Duration and Degree of Vascular Bioeffects—Work in Progress

Tomihiko Hirokawa, PhD, Raffi Karshafian, MSc, Charles J. Pavlin, MD, PhD and Peter N. Burns, PhD

Department of Medical Biophysics, University of Toronto and Department of Imaging Research, Sunnybrook Health Sciences Centre, Toronto, Ontario, Canada (T.H., R.K., P.N.B.); and Mount Sinai Hospital, Toronto, Ontario, Canada (C.J.P.).

Address correspondence to Peter N. Burns, PhD, Imaging Research, S660, Sunnybrook Health Sciences Centre, 2075 Bayview Ave, Toronto ON M4N 3M5, Canada. E-mail: burns{at}swri.ca

Objective. The purpose of this study was to investigate the presence and duration of vascular permeability changes induced by the combination of ultrasound and an intravascular microbubble contrast agent in the rabbit eye. Methods. Five eyes were studied in 8 anaesthetized rabbits. Insonation was performed with a diagnostic B-mode system (center frequency = 2 MHz; mechanical index [MI] = 0.2 and 1.7) for 5 minutes after administration of perflutren microbubbles (0.07 mL/kg). Fluorescein fundus angiography was performed before and 3 minutes after insonation; at 6 minutes, color fundus photography was used to assess the dye leakage, bleeding, and alteration of the diameter of fundus vessels. Results. Alteration of fundus vessel diameters was observed in 1 of 5 cases at a low MI and in 4 of 5 cases at a higher MI. In 1 case, leakage of fluorescein indicated increased permeability at the higher MI. No bleeding was detected in any case. Conclusions. The permeability change induced by insonation and this dose of an ultrasound contrast agent appears to be transient under the conditions studied, although the time delay between insonation and optical assessment limits the completeness of the findings. This preliminary study may be relevant to drug delivery strategies using ultrasound and microbubbles.

Key Words: bioeffects • rabbit eye vasoconstriction • therapeutic ultrasound • ultrasound contrast agents

Abbreviations: MI, mechanical index

HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS
Copyright © 2007 by the American Institute of Ultrasound in Medicine.