Blood-brain barrier disruption by low-frequency ultrasound.

Abstract

BACKGROUND AND PURPOSE:

A recent study showed a dramatic increase in cerebral hemorrhage comprising atypical locations with low-frequency ultrasound-mediated recombinant tissue plasminogen activator-thrombolysis in humans. Here, we provide a possible explanation for this phenomenon by a side effect observed in a study using the similar ultrasound device.

METHODS:

The study was originally undertaken to investigate by transcranial Doppler sonography, positron emission tomography and perfusion MRI whether transcranial application of wide-field low-frequency ultrasound (300 kHz) improves cerebral hemodynamics in patients with cerebral small vessel disease.

RESULTS:

Showing no clear positive effect on cerebral hemodynamics in 4 patients and on cerebral perfusion (positron emission tomography) in 2 patients, the study has been terminated early because of a remarkable side effect in the first patient (a 62 year-old man) undergoing perfusion-MRI: detection of frontoparietal extravasation of Gadolinium contrast agent (applied during MRI perfusion imaging preinsonation) on MRI immediately postinsonation.

CONCLUSIONS:

Abnormal permeability of the human blood-brain barrier can be induced by wide-field low-frequency insonation. The observed excessive bleeding rate with low-frequency sonothrombolysis might thus be attributable to primary blood-brain barrier disruption by ultrasound.

• Authors: Matthias Reinhard, Andreas Hetzel, Sebastian Krüger, Stefan Kretzer, Jochen Talazko, Sargon Ziyeh, Johannes Weber, Thomas Els
• Journal: Stroke (Stroke) Vol. 37 Issue 6 Pg. 1546-8 (Jun 2006) ISSN: 1524-4628 [Electronic] United States
• PMID: 16645131 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't)

Topics

• Aged
• Blood-Brain Barrier (radiation effects)
• Brain Ischemia (diagnosis, physiopathology, therapy)
• Cerebrovascular Circulation (radiation effects)
• Extravasation of Diagnostic and Therapeutic Materials (etiology)
• Frontal Lobe (blood supply)
• Hemodynamics (radiation effects)
• Humans
• Magnetic Resonance Imaging
• Male
• Middle Aged
• Parietal Lobe (blood supply)
• Positron-Emission Tomography
• Ultrasonic Therapy (adverse effects)
• Ultrasonography, Doppler, Transcranial