This Article Full Text Full Text (PDF) Correction (v111,pe443) All Versions of this Article: 111/21/2776    most recent CIRCULATIONAHA.104.483024v1 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 Devuyst, G. Articles by Bogousslavsky, J. Search for Related Content PubMed PubMed Citation Articles by Devuyst, G. Articles by Bogousslavsky, J. Pubmed/NCBI databases Medline Plus Health Information Carotid Artery Disease Ultrasound Related Collections Carotid Stenosis Imaging Doppler ultrasound, Transcranial Doppler etc.

(Circulation. 2005;111:2776-2782.)
© 2005 American Heart Association, Inc.

Imaging

Ultrasound Measurement of the Fibrous Cap in Symptomatic and Asymptomatic Atheromatous Carotid Plaques

Gérald Devuyst, MD; Patrick Ruchat, MD; Theodoros Karapanayiotides, MD; Lisa Jonasson, MS; Olivier Cuisinaire, PhD; Johannes-Alexander Lobrinus, MD; Marc Pusztaszeri, MD; Askenadios Kalangos, MD; Paul-André Despland, MD; Jean-Philippe Thiran, PhD; Julien Bogousslavsky, MD

From the Department of Neurology (G.D., T.K., P.-A.D., J.B.), Division of Neuropathology (J.-A.L., M.P.), and Department of Cardiovascular Surgery (P.R.), Centre Hospitalier Universitaire Vaudois, Lausanne, Switzerland; Signal Processing Institute (L.J., O.C., J.-P.T.), Swiss Federal Institute of Technology, Lausanne, Switzerland; and Department of Cardiovascular Surgery, Geneva University Hospital (A.K.), Geneva, Switzerland.

Correspondence to Gérald Devuyst, MD, Department of Neurology, Centre Hospitalier Universitaire Vaudois, Rue du Bugnon 46, 1011 Lausanne, Switzerland. E-mail gerald.devuyst{at}chuv.hospvd.ch

Received June 8, 2004; revision received January 25, 2005; accepted February 22, 2005.

Background— Fibrous cap thickness (FCT) is an important determinant of atheroma stability. We evaluated the feasibility and potential clinical implications of measuring the FCT of internal carotid artery plaques with a new ultrasound system based on boundary detection by dynamic programming.

Methods and Results— We assessed agreement between ultrasound-obtained FCT values and those measured histologically in 20 patients (symptomatic [S]=9, asymptomatic [AS]=11) who underwent carotid endarterectomy for stenosing (>70%) carotid atheromas. We subsequently measured in vivo the FCT of 58 stenosing internal carotid artery plaques (S=22, AS=36) in 54 patients. The accuracy in discriminating symptomatic from asymptomatic plaques was assessed by receiver operating characteristic curves for the minimal, mean, and maximal FCT. Decision FCT thresholds that provided the best correct classification rates were identified. Agreement between ultrasound and histology was excellent, and interobserver variability was small. Ultrasound showed that symptomatic atheromas had thinner fibrous caps (S versus AS, median [95% CI]: minimal FCT=0.42 [0.34 to 0.48] versus 0.50 [0.44 to 0.53] mm, P=0.024; mean FCT=0.58 [0.52 to 0.63] versus 0.79 [0.69 to 0.85] mm, P<0.0001; maximal FCT=0.73 [0.66 to 0.92] versus 1.04 [0.94 to 1.20] mm, P<0.0001). Mean FCT measurement demonstrated the best discriminatory accuracy (area under the curve [95% CI]: minimal 0.74 [0.61 to 0.87]; mean 0.88 [0.79 to 0.97]; maximal 0.82 [0.71 to 0.93]). The decision threshold of 0.65 mm (mean FTC) demonstrated the best correct classification rate (82.8%; positive predictive value 75%, negative predictive value 88.2%).

Conclusions— FCT measurement of carotid atheroma with ultrasound is feasible. Discrimination of symptomatic from asymptomatic plaques with mean FCT values is good. Prospective studies should determine whether this ultrasound marker is reliable.

Key Words: ultrasonics • plaque • carotid arteries • atherosclerosis • cerebrovascular disorders

This article has been cited by other articles:

				J. N. Redgrave, P. Gallagher, J. K. Lovett, and P. M. Rothwell Critical Cap Thickness and Rupture in Symptomatic Carotid Plaques: The Oxford Plaque Study Stroke, June 1, 2008; 39(6): 1722 - 1729. [Abstract] [Full Text] [PDF]

				T. Karapanayiotides Letter by Karapanayiotides Regarding Article, "Histological Assessment of 526 Symptomatic Carotid Plaques in Relation to the Nature and Timing of Ischemic Symptoms: the Oxford Plaque Study" Circulation, November 21, 2006; 114(21): e598 - e598. [Full Text] [PDF]

				T. Karapanayiotides and G. Devuyst Fibrous Cap Thickness and Stability of Carotid Atheromata Stroke, October 1, 2006; 37(10): 2451 - 2451. [Full Text] [PDF]

				Z.-Y. Li, T. Tang, S. P.S. Howarth, and J. H. Gillard Response to Letter by Karapanayiotides and Devuyst Stroke, October 1, 2006; 37(10): 2452 - 2452. [Full Text] [PDF]

				T. Karapanayiotides and J. Bogousslavsky Carotid Stenosis: Looking Beyond the Lumen With Ultrasound Stroke, July 1, 2006; 37(7): 1646 - 1646. [Full Text] [PDF]

				B. A. Wasserman, R. J. Wityk, H. H. Trout III, and R. Virmani Response to Letter by Karapanayiotides et al Stroke, July 1, 2006; 37(7): 1647 - 1647. [Full Text] [PDF]