Objective. —To determine whether carotid endarterectomy provides protection against subsequent cerebral ischemia in men with ischemic symptoms in the distribution of significant (>50%) ipsilateral internal carotid artery stenosis. Design. —Prospective, randomized, multicenter trial. Setting. —Sixteen university-affiliated Veterans Affairs medical centers. Patients. —Men who presented within 120 days of onset of symptoms that were consistent with transient ischemic attacks, transient monocular blindness, or recent small completed strokes between July 1988 and February 1991. Among 5000 patients screened, 189 individuals were randomized with angiographic internal carotid artery stenosis greater than 50% ipsilateral to the presenting symptoms. Forty-eight eligible patients who refused entry were followed up outside of the trial. Outcome Measures. —Cerebral infarction or crescendo transient ischemic attacks in the vascular distribution of the original symptoms or death within 30 days of randomization. Intervention. —Carotid endarterectomy plus the best medical care (n = 91) vs the best medical care alone (n=98). Results. —At a mean follow-up of 11.9 months, there was a significant reduction in stroke or crescendo transient ischemic attacks in patients who received carotid endarterectomy (7.7%) compared with nonsurgical patients (19.4%), or an absolute risk reduction of 11.7% (P=.011). The benefit of surgery was more profound in patients with internal carotid artery stenosis greater than 70% (absolute risk reduction, 17.7%;P=.004). The benefit of surgery was apparent within 2 months after randomization, and only one stroke was noted in the surgical group beyond the 30-day perioperative period. Conclusions. —For a selected cohort of men with symptoms of cerebral or retinal ischemia in the distribution of a high-grade internal carotid artery stenosis, carotid endarterectomy can effectively reduce the risk of subsequent ipsilateral cerebral ischemia. The risk of cerebral ischemia in this subgroup of patients is considerably higher than previously estimated. (JAMA. 1991;266:3289-3294)

Carotid endarterectomy and prevention of cerebral ischemia in symptomatic carotid stenosis. Commentary

ESVS guidelines. Invasive treatment for carotid stenosis: indications, techniques.

Europejskie Towarzystwo Chirurgii Naczyniowej (ESVS) zgromadzilo grupe ekspertow zajmujących sie patologią
tetnic szyjnych (CAD) w celu stworzenia uaktualnionych wytycznych dotyczących inwazyjnego leczenia
zwezenia tetnicy szyjnej. Zalecenia oceniano, przypisując im odpowiedni poziom dowodow. Wykonanie endarterektomii
tetnicy szyjnej (CEA) zaleca sie u pacjentow z objawami, u ktorych zwezenie jest wieksze niz
50%, jeśli czestośc wystepowania udaru mozgu/zgonu w okresie okolooperacyjnym wynosi mniej niz 6% [A];
najlepiej, aby CEA wykonano w ciągu 2 tygodni od wystąpienia ostatnich objawow [A]. Zabieg ten zaleca sie
takze u mezczyzn, u ktorych nie stwierdza sie objawow, w wieku ponizej 75 rz., ze zwezeniem wynoszącym
70–99%, jeśli czestośc wystepowania udaru mozgu/zgonu w okresie okolooperacyjnym wynosi mniej niz 3%
[A]. Korzyści z przeprowadzenia CEA u kobiet, u ktorych nie wystepują objawy, są istotnie mniejsze niz u mezczyzn
[A], dlatego wykonanie tego zabiegu powinno rozwazac sie tylko u mlodszych kobiet bez dodatkowych
obciązen. Preferuje sie przeprowadzanie angioplastyki z uzyciem laty nad pierwotnym zamknieciem tetnicy
[A]. Przed zabiegiem CEA, w jego trakcie i po nim chorym nalezy zalecic stosowanie kwasu acetylosalicylowego w dawce dobowej 75–325 mg i terapie statynami [A]. Zabieg stentowania tetnicy szyjnej (CAS) powinno
sie wykonywac jedynie u pacjentow, u ktorych przeprowadzenie zabiegu CEA wiąze sie z duzym ryzykiem,
w duzych ośrodkach o udokumentowanym malym ryzyku wystąpienia zgonu i udaru mozgu w okresie okolooperacyjnym
lub w ramach randomizowanych kontrolowanych badan klinicznych [C]. Zabieg CAS nalezy wykonywac, stosując jednocześnie podwojne leczenie przeciwplytkowe z uzyciem kwasu acetylosalicylowego
i klopidogrelu [A]. Wykorzystanie systemow protekcji mozgu prawdopodobnie jest korzystne [C].
 Acta Angiol 2010; 16, 4: 190–215

/pdf/european-society-of-vascular-surgery-esvs-guidelines-41kph5h7hg.pdf

European Society of Vascular Surgery (ESVS) guidelines. Invasive treatment for carotid stenosis: indications, techniques

OBJECTIVE. This and its companion article address the 10 most frequently asked questions that radiologists face when planning, performing, processing, and interpreting different MR perfusion studies in CNS imaging. CONCLUSION. Perfusion MRI is a promising tool in assessing stroke, brain tumors, and patients with neurodegenerative diseases. Most of the impediments that have limited the use of perfusion MRI can be overcome to allow integration of these methods into modern neuroimaging protocols.

/pdf/perfusion-mri-the-five-most-frequently-asked-clinical-1or4cw7w4u.pdf

Perfusion MRI: the five most frequently asked clinical questions.

In a well-characterized and large data set, we have found considerable variation in the accuracy of core and penumbra detection, and the perfusion thresholds used to determine them, with commonly used perfusion algorithms.

Perfusion CT in Acute Stroke: A Comprehensive Analysis of Infarct and Penumbra

BACKGROUND AND PURPOSE: Plaque morphologic features have been suggested as a complement to luminal narrowing measurements for assessing the risk of stroke associated with carotid atherosclerotic disease, giving rise to the concept of “vulnerable plaque.” The purpose of this study was to evaluate the ability of multidetector-row CT angiography (CTA) to assess the composition and characteristics of carotid artery atherosclerotic plaques with use of histologic examination as the gold standard. MATERIALS AND METHODS: Eight patients with transient ischemic attacks who underwent carotid CTA and “en bloc” endarterectomy were enrolled in a prospective study. An ex vivo micro-CT study of each endarterectomy specimen was obtained, followed by histologic examination. A systematic comparison of CTA images with histologic sections and micro-CT images was performed to determine the CT attenuation associated with each component of the atherosclerotic plaques. A computer algorithm was subsequently developed that automatically identifies the components of the carotid atherosclerotic plaques, based on the density of each pixel. A neuroradiologist9s reading of this computer analysis was compared with the interpretation of the histologic slides by a pathologist with respect to the types and characteristics of the carotid plaques. RESULTS: There was a 72.6% agreement between CTA and histologic examination in carotid plaque characterization. CTA showed perfect concordance for calcifications. A significant overlap between densities associated with lipid-rich necrotic core, connective tissue, and hemorrhage limited the reliability of individual pixel readings to identify these components. However, CTA showed good correlation with histologic examination for large lipid cores (κ = 0.796; P P = .102). CTA performed well in detecting ulcerations (κ = 0.855) and in measuring the fibrous cap thickness ( R 2 = 0.77; P CONCLUSION: The composition of carotid atherosclerotic plaques determined by CTA reflects plaque composition defined by histologic examination.

http://www.ajnr.org/content/ajnr/29/5/875.full.pdf

S. Abedin

Papers

High-resolution CT imaging of carotid artery atherosclerotic plaques.