Abstract
The purpose of this case-control study was to determine whether an asymmetry of size of the intracranial internal carotid artery (ICA) on 3D time-of-flight MR angiography (MRA) is predictive of a high-grade cervical ICA stenosis. Ninety-six stroke/TIA consecutive patients were recruited for the study, of whom 32 had unilateral high-grade ICA stenosis (≥70% NASCET) and were included into the case group, and the remaining 64 did not have such high-grade stenosis and were included in the control group. On intracranial MRA, two observers, blinded to the characteristics of cervical ICA stenosis, independently searched for qualitative size asymmetry between ICAs and measured the cross-sectional surface of the intracranial ICAs. An intracranial size asymmetry was seen in 28 of the 32 high-grade stenoses by both readers, and in 10 (reader1) and 8 (reader2) of the 64 controls (sensitivity = 88%, specificity = 84–88%). In patients without agenesia of the A1 segment of the circle of Willis (n = 70), sensitivity was ≥90% and specificity = 96%. Surfaces ratios were significantly different (p < 0.001) between cases and controls. However, using ROC curves analysis, the quantitative processing did not improve the detection when compared with the qualitative assessment of intracranial ICA asymmetry. A size asymmetry of the intracranial ICAs reveals the presence of an underlying high-grade cervical stenosis, with a high degree of confidence, especially in patients without anatomical variant of the anterior part of the circle of Willis. This sign may allow an early detection of high-grade cervical carotid stenosis in stroke patients before dedicated neck imaging is performed.
Similar content being viewed by others
References
Ozsarlak O, Van Goethem JW, Maes M, Parizel PM (2004) MR angiography of the intracranial vessels: technical aspects and clinical applications. Neuroradiology 46:955–992
Lövblad KO, Baird AE (2006) Actual diagnostic approach to the acute stroke patient. Eur Radiol 16:1253–1269
Thurnher MM, Castillo M (2005) Imaging in acute stroke. Eur Radiol 15:408–415
Fairhead JF, Mehta Z, Rothwell PM (2005) Population-based study of delays in carotid imaging and surgery and the risk of recurrent stroke. Neurology 65:371–375
Rutgers DR, Blankensteijn JD, van der Grond J (2000) Preoperative MRA flow quantification in CEA patients: flow differences between patients who develop cerebral ischemia and patients who do not develop cerebral ischemia during cross-clamping of the carotid artery. Stroke 31:3021–3028
Ascher E, Markevich N, Hingorani AP, Kallakuri S, Gunduz Y (2002) Internal carotid artery flow volume measurement and other intraoperative duplex scanning parameters as predictors of stroke after carotid endarterectomy. J Vasc Surg 35:439–444
Caramia F, Santoro A, Pantano P, Passacantilli E, Guidetti G, Pierallini A, Fantozzi LM, Cantore GP, Bozzao L (2001) Cerebral hemodynamics on MR perfusion images before and after bypass surgery in patients with giant intracranial aneurysms. AJNR Am J Neuroradiol 22:1704–1710
Wasserman BA, Lin W, Tarr RW, Haacke EM, Muller E (1995) Cerebral arteriovenous malformations: flow quantitation by means of two-dimensional cardiac-gated phase-contrast MR imaging. Radiology 194:681–686
Rothwell PM, Eliasziw M, Gutnikov SA, Warlow CP, Barnett HJ (2004) Endarterectomy for symptomatic carotid stenosis in relation to clinical subgroups and timing of surgery. Lancet 363:915–924
Adams HP Jr, Adams RJ, Brott T, del Zoppo GJ, Furlan A, Goldstein LB, Grubb RL, Higashida R, Kidwell C, Kwiatkowski TG, Marler JR, Hademenos GJ (2003) Guidelines for the early management of patients with ischemic stroke: A scientific statement from the Stroke Council of the American Stroke Association. Stroke 34:1056–1083
Soinne L, Helenius J, Tatlisumak T, Saimanen E, Salonen O, Lindsberg PJ, Kaste M (2003) Cerebral hemodynamics in asymptomatic and symptomatic patients with high-grade carotid stenosis undergoing carotid endarterectomy. Stroke 34:1655–1661
Surikova I, Meisel S, Siebler M, Wittsack HJ, Seitz RJ (2006) Significance of the perfusion-diffusion mismatch in chronic cerebral ischemia. J Magn Reson Imaging 24:771–778
Hendrikse J, van Raamt AF, van der Graaf Y, Mali WP, van der Grond J (2005) Distribution of cerebral blood flow in the circle of Willis. Radiology 235:184–189
Author information
Authors and Affiliations
Corresponding author
Rights and permissions
About this article
Cite this article
Naggara, O., Touzé, E., Seiller, N. et al. Asymmetry of intracranial internal carotid artery on 3D TOF MR angiography: a sign of unilateral extracranial stenosis. Eur Radiol 18, 1038–1042 (2008). https://doi.org/10.1007/s00330-007-0835-3
Received:
Revised:
Accepted:
Published:
Issue Date:
DOI: https://doi.org/10.1007/s00330-007-0835-3