This Article Full Text Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Services Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Kriegshauser, J. S. Articles by Nelson, K. D. Search for Related Content PubMed PubMed Citation Articles by Kriegshauser, J. S. Articles by Nelson, K. D.

Carotid Pseudostring Sign From Vasa Vasorum Collaterals

Department of Radiology, Mayo Clinic, Scottsdale, Arizona USA.

Address correspondence and reprint requests to J. Scott Kriegshauser, MD, Mayo Clinic Scottsdale, 13400 E Shea Blvd, Scottsdale, AZ 85259 USA. Email: skriegshauser{at}mayo.edu.

Objective. To describe the spectral and color Doppler imaging findings in 2 cases of internal carotid artery occlusion with vasa vasorum collateral flow, which we term the "pseudostring sign." Methods. Spectral and color Doppler imaging findings in both cases were reviewed. Magnetic resonance angiography in 2 cases and conventional angiography in 1 case were also reviewed. Results. Both patients had color Doppler images showing that the internal carotid artery was a narrow, stringlike vessel with arterial flow that had normal spectral Doppler features (velocity <125 cm/s with a normal waveform). Magnetic resonance angiography in 1 patient showed total occlusion of the proximal internal carotid artery with patent vasa vasorum collaterals reconstituting the lumen distally. In the second patient, magnetic resonance angiography showed total occlusion of the proximal internal carotid artery, and conventional angiography showed proximal occlusion with collateral flow through the vasa vasorum. Conclusions. Proximal internal carotid artery occlusion with vasa vasorum collateral flow should be considered when color Doppler imaging shows a seemingly narrow internal carotid artery with tortuosity and normal spectral Doppler features. Patients with these features should not undergo carotid endarterectomy directly on the basis of only the Doppler findings.

Key Words: carotid occlusion • string sign • vasa vasorum

Abbreviations: CCA, common carotid artery • ICA, internal carotid artery

This article has been cited by other articles:

				J. P Soares-Fernandes, M. Ribeiro, Z. Magalhaes, and J. F Rocha The sonographic pitfall of carotid collateralisation via the vasa vasorum J. Neurol. Neurosurg. Psychiatry, November 1, 2007; 78(11): 1270 - 1270. [Full Text] [PDF]