Functional assessment of high-grade ICA stenosis with duplex ultrasound and transcranial Doppler
2012 (English)In: Clinical Physiology and Functional Imaging, ISSN 1475-0961, E-ISSN 1475-097X, Vol. 32, no 3, 241-246 p.Article in journal (Refereed) Published
Background: Duplex ultrasound (DUS) has shown a andgt;90% accuracy compared to angiography, concerning the degree of internal carotid artery (ICA) stenosis. However, uncertainty may occur in a severe stenosis, in which peak systolic velocity (PSV) may decrease owing to high flow resistance or high backward pressure. We investigated intracranial collateral flows using transcranial Doppler (TCD) to further evaluate the hemodynamic significance of high-grade ICA stenosis. Methods: In this retrospective study, 320 consecutive symptomatic patients were examined. The degree of ICA stenosis and collateral capacity in the circle of Willis was investigated by DUS and TCD. In addition, magnetic resonance angiography (MRA) was added in a subgroup of 204 patients. The criterion for hemodynamic significant ICA stenosis was established collateral flow. Results: In 91% of all symptomatic vessels (291 vessels), an ICA stenosis of 70% was found. Established collateral flow always indicated precerebral carotid artery disease of 70%. Furthermore, in 11% of the whole study material, collateral reserve capacity was found despite high-grade (70%) ICA stenosis. PSV in ICA andlt; 2 5 m s) 1 was combined with established collateral flow and MRA stenosis of 70% in 9% (19 arterial systems). In 4%, doubt existed concerning the degree of stenosis after DUS. Conclusion: Transcranial Doppler helps to determine whether an ICA stenosis is of hemodynamic significance and to assess collateral patterns. Established collateral blood flow will help to identify patients with 70% (ECST) carotid artery disease. TCD might be of value when flow velocity criteria combined with plaque assessment by DUS are inclusive. Other diagnostic methods may also be considered.
Place, publisher, year, edition, pages
Wiley-Blackwell , 2012. Vol. 32, no 3, 241-246 p.
carotid artery disease, collateral blood flow, duplex ultrasound, transcranial Doppler
Medical and Health Sciences
IdentifiersURN: urn:nbn:se:liu:diva-77094DOI: 10.1111/j.1475-097X.2011.01118.xISI: 000302545300012OAI: oai:DiVA.org:liu-77094DiVA: diva2:524961