This Article Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Citation Map Services Email this article to a friend Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Request Permissions Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Siebler, M. Articles by Steinmetz, H. Search for Related Content PubMed PubMed Citation Articles by Siebler, M. Articles by Steinmetz, H.

Stroke, Vol 23, 1652-1654, Copyright © 1992 by American Heart Association

ARTICLES

Detection of intracranial emboli in patients with symptomatic extracranial carotid artery disease

M Siebler, M Sitzer and H Steinmetz
Department of Neurology, Heinrich-Heine-University, Dusseldorf, FRG.

BACKGROUND AND PURPOSE: Cerebral embolism from extracranial sources is an important cause of ischemic stroke. The purpose of this limited study using long-term transcranial Doppler ultrasonographic monitoring was to estimate the frequency of clinically silent intracranial embolisms in patients with symptomatic extracranial carotid artery disease. SUMMARY OF REPORT: By means of a 2-MHz pulsed-wave transcranial Doppler instrumentation, three consecutive patients with extracranial internal carotid artery stenosis (n = 2) or occlusion (n = 1) and recurrent ipsilateral ischemic events were monitored (19 hours total recording time). In addition, 10 control subjects without cerebrovascular disease were studied (25 hours total recording time). Formed-element emboli were defined as distinct signals within the fast Fourier-transform Doppler spectrum that were < 70 msec in duration and > 9dB greater in intensity than the background signal. Clinically silent formed-element embolism of ophthalmic or cerebral arteries was demonstrated in all three patients. Embolic events occurred only in the territory of the symptomatic internal carotid artery. The average rate of cerebral embolization at transcranial Doppler ultrasonography was 4.1/hr, with a mean signal duration of 47 msec. No emboli were found in control subjects. CONCLUSIONS: The observed high frequency of silent embolism of the intracranial arteries detected by transcranial Doppler monitoring in patients with recurrently symptomatic extracranial carotid artery disease should encourage studies of the prognostic and therapeutic implications of this method.

This article has been cited by other articles:

				R. Sztajzel, I. Momjian-Mayor, M. Comelli, and S. Momjian Correlation of Cerebrovascular Symptoms and Microembolic Signals With the Stratified Gray-Scale Median Analysis and Color Mapping of the Carotid Plaque Stroke, March 1, 2006; 37(3): 824 - 829. [Abstract] [Full Text] [PDF]

				I. Momjian-Mayor and J.-C. Baron The Pathophysiology of Watershed Infarction in Internal Carotid Artery Disease: Review of Cerebral Perfusion Studies Stroke, March 1, 2005; 36(3): 567 - 577. [Abstract] [Full Text] [PDF]

				K. Kimura, K. Minematsu, M. Koga, R. Arakawa, M. Yasaka, H. Yamagami, K. Nagatsuka, H. Naritomi, and T. Yamaguchi Microembolic Signals and Diffusion-weighted MR Imaging Abnormalities in Acute Ischemic Stroke AJNR Am. J. Neuroradiol., June 1, 2001; 22(6): 1037 - 1042. [Abstract] [Full Text] [PDF]

				R. G. J. Gibbs, M. Sian, A. W. M. Mitchell, R. M. Greenhalgh, A. H. Davies, and N. Carey Chlamydia pneumoniae Does Not Influence Atherosclerotic Plaque Behavior in Patients With Established Carotid Artery Stenosis Stroke, December 1, 2000; 31(12): 2930 - 2935. [Abstract] [Full Text] [PDF]

				T. Rundek, M. R. Di Tullio, R. R. Sciacca, I. V. Titova, J. P. Mohr, S. Homma, and R. L. Sacco Association Between Large Aortic Arch Atheromas and High-Intensity Transient Signals in Elderly Stroke Patients Stroke, December 1, 1999; 30(12): 2683 - 2686. [Abstract] [Full Text] [PDF]

				R. W. M. Keunen, C. J. Stam, D. L. J. Tavy, W. H. Mess, B. M. Titulaer, and R. G. A. Ackerstaff Preliminary Report of Detecting Microembolic Signals in Transcranial Doppler Time Series With Nonlinear Forecasting Stroke, August 1, 1998; 29(8): 1638 - 1643. [Abstract] [Full Text] [PDF]

				J. Molloy, N. Khan, and H. S. Markus Temporal Variability of Asymptomatic Embolization in Carotid Artery Stenosis and Optimal Recording Protocols Stroke, June 1, 1998; 29(6): 1129 - 1132. [Abstract] [Full Text] [PDF]

				A. Notzold, D. W. Droste, G. Hagedorn, S. Berndt, M. Kaps, B. Graf, and H. H. Sievers Circulating Microemboli in Patients After Aortic Valve Replacement With Pulmonary Autografts and Mechanical Valve Prostheses Circulation, September 16, 1997; 96(6): 1843 - 1846. [Abstract] [Full Text]

				D. W. Droste, G. Hagedorn, A. Notzold, H.-J. Siemens, H. H. Sievers, and M. Kaps Bigated Transcranial Doppler for the Detection of Clinically Silent Circulating Emboli in Normal Persons and Patients With Prosthetic Cardiac Valves Stroke, March 1, 1997; 28(3): 588 - 592. [Abstract] [Full Text]

				C. Specker, J. Rademacher, D. Sohngen, M. Sitzer, I. Janda, M. Siebler, H. Steinmetz, and M. Schneider Cerebral microemboli in patients with antiphospholipid syndrome Lupus, January 1, 1997; 6(8): 638 - 644. [Abstract] [PDF]

				E. V. Van Zuilen, W. H. Mess, C. Jansen, I. Van Der Tweel, J. Van Gijn, and R. G.A. Ackerstaff Automatic Embolus Detection Compared With Human Experts: A Doppler Ultrasound Study Stroke, October 1, 1996; 27(10): 1840 - 1843. [Abstract] [Full Text]

				J. Molloy and H. S. Markus Multigated Doppler Ultrasound in the Detection of Emboli in a Flow Model and Embolic Signals in Patients Stroke, September 1, 1996; 27(9): 1548 - 1552. [Abstract] [Full Text]

				J. L. Smith, D. H. Evans, L. Fan, M. E. Gaunt, N. J.M. London, P. R.F. Bell, and A. R. Naylor Interpretation of Embolic Phenomena During Carotid Endarterectomy Stroke, December 1, 1995; 26(12): 2281 - 2284. [Abstract] [Full Text]

				U. Sliwka, F.-P. Job, D. Wissuwa, R. R. Diehl, F.-A. Flachskampf, P. Hanrath, and J. Noth Occurrence of Transcranial Doppler High-Intensity Transient Signals in Patients With Potential Cardiac Sources of Embolism : A Prospective Study Stroke, November 1, 1995; 26(11): 2067 - 2070. [Abstract] [Full Text]

				D. C. Tong and G. W. Albers Transcranial Doppler–Detected Microemboli in Patients With Acute Stroke Stroke, September 1, 1995; 26(9): 1588 - 1592. [Abstract] [Full Text]

				S. K. Brækken, D. Russell, R. Brucher, and J. Svennevig Incidence and Frequency of Cerebral Embolic Signals in Patients With a Similar Bileaflet Mechanical Heart Valve Stroke, July 1, 1995; 26(7): 1225 - 1230. [Abstract] [Full Text]

				L. Valton, V. Larrue, P. Arrue, G. Geraud, and A. Bes Asymptomatic Cerebral Embolic Signals in Patients With Carotid Stenosis : Correlation With Appearance of Plaque Ulceration on Angiography Stroke, May 1, 1995; 26(5): 813 - 815. [Abstract] [Full Text]

				E. V. van Zuilen, F. L. Moll, F. E.E. Vermeulen, H. W. Mauser, J. van Gijn, and R. G.A. Ackerstaff Detection of Cerebral Microemboli by Means of Transcranial Doppler Monitoring Before and After Carotid Endarterectomy Stroke, February 1, 1995; 26(2): 210 - 213. [Abstract] [Full Text]

				M. Sturzenegger, J. H. Beer, and F. Rihs Monitoring Combined Antithrombotic Treatments in Patients With Prosthetic Heart Valves Using Transcranial Doppler and Coagulation Markers Stroke, January 1, 1995; 26(1): 63 - 69. [Abstract] [Full Text]