L J Kappelle

University Medical Center Utrecht, Utrecht, Utrecht, Netherlands

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Publications (356)1359.12 Total impact

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    ABSTRACT: Blood oxygenation-level dependent (BOLD) magnetic resonance imaging signal changes in response to stimuli have been used to evaluate age-related changes in neuronal activity. Contradictory results from these types of experiments have been attributed to differences in cerebral blood flow (CBF) and cerebral metabolic rate of oxygen (CMRO2 ). To clarify the effects of these physiological parameters, we investigated the effect of age on baseline CBF and CMRO2 . Twenty young (mean ± sd age, 28 ± 3 years), and 45 older subjects (66 ± 4 years) were investigated. A dual-echo pseudocontinuous arterial spin labeling (ASL) sequence was performed during normocapnic, hypercapnic, and hyperoxic breathing challenges. Whole brain and regional gray matter values of CBF, ASL cerebrovascular reactivity (CVR), BOLD CVR, oxygen extraction fraction (OEF), and CMRO2 were calculated. Whole brain CBF was 49 ± 14 and 40 ± 9 ml/100 g/min in young and older subjects respectively (P < 0.05). Age-related differences in CBF decreased to the point of nonsignificance (B=-4.1, SE=3.8) when EtCO2 was added as a confounder. BOLD CVR was lower in the whole brain, in the frontal, in the temporal, and in the occipital of the older subjects (P<0.05). Whole brain OEF was 43 ± 8% in the young and 39 ± 6% in the older subjects (P = 0.066). Whole brain CMRO2 was 181 ± 60 and 133 ± 43 µmol/100 g/min in young and older subjects, respectively (P<0.01). Age-related differences in CBF could potentially be explained by differences in EtCO2 . Regional CMRO2 was lower in older subjects. BOLD studies should take this into account when investigating age-related changes in neuronal activity. Hum Brain Mapp, 2015. © 2015 Wiley Periodicals, Inc. © 2015 Wiley Periodicals, Inc.
    Human Brain Mapping 07/2015; DOI:10.1002/hbm.22891 · 6.92 Impact Factor
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    ABSTRACT: Aneurysms of the extracranial carotid artery (ECAA) are rare. Several treatments have been developed over the last 20 years, yet the preferred method to treat ECAA remains unknown. This paper is a review of all available literature on the risk of complications and long-term outcome after conservative or invasive treatment of patients with ECAA. Reports on ECAA treatment until July 2014 were searched in PubMed and Embase using the key words aneurysm, carotid, extracranial, and therapy. A total of 281 articles were identified. Selected articles were case reports (n = 179) or case series (n = 102). Papers with fewer than 10 patients were excluded, resulting in the final selection of 39 articles covering a total of 1,239 patients. Treatment consisted of either conservative treatment in 11% of the cases or invasive treatment in 89% of the cases. Invasive treatment comprised surgery in 94%, endovascular approach in 5%, and a hybrid approach in 1% of the patients. The most common complication described after invasive therapy was cranial nerve damage, which occurred in 11.8% of patients after surgery. The 30 day mortality rate and stroke rate in conservatively treated patients was 4.67% and 6.67%, after surgery 1.91% and 5.16%. Information on confounders in the present study was incomplete. Therefore, adjustments to correct for confounding by indication could not be done. This review summarizes the largest available series in the literature on ECAA management. The number of ECAAs reported in current literature is scarce. The early and long-term outcome of invasive treatment in ECAA is favorable; however, cranial nerve damage after surgery occurs frequently. Unfortunately, due to limitations in reporting of results and confounding by indication in the available literature, it was not possible to determine the optimal treatment strategy. There is a need for a multicenter international registry to reveal the optimal treatment for ECAA. Copyright © 2015 European Society for Vascular Surgery. Published by Elsevier Ltd. All rights reserved.
    European journal of vascular and endovascular surgery: the official journal of the European Society for Vascular Surgery 06/2015; DOI:10.1016/j.ejvs.2015.05.002 · 3.07 Impact Factor
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    ABSTRACT: Our aim is to compare the effect of type 2 diabetes on recurrent major cardiovascular events (MCVE) for patients with symptomatic vascular disease at different locations. A total of 6,841 patients from the single-center, prospective Secondary Manifestations of ARTerial disease (SMART) cohort study from Utrecht, the Netherlands, with clinically manifest vascular disease with (n = 1,155) and without (n = 5,686) type 2 diabetes were monitored between 1996 and 2013. The effect of type 2 diabetes on recurrent MCVE was analyzed with Cox proportional hazard models, stratified for disease location (cerebrovascular disease, peripheral artery disease, abdominal aortic aneurysm, coronary artery disease, or polyvascular disease, defined as ≥2 vascular locations). Five-year risks for recurrent MCVE were 9% in cerebrovascular disease, 9% in peripheral artery disease, 20% in those with an abdominal aortic aneurysm, 7% in coronary artery disease, and 21% in polyvascular disease. Type 2 diabetes increased the risk of recurrent MCVE in coronary artery disease (hazard ratio [HR] 1.67; 95% CI 1.25-2.21) and seemed to increase the risk in cerebrovascular disease (HR 1.36; 95% CI 0.90-2.07), while being no risk factor in polyvascular disease (HR 1.12; 95% CI 0.83-1.50). Results for patients with peripheral artery disease (HR 1.42; 95% CI 0.79-2.56) or an abdominal aortic aneurysm (HR 0.93; 95% CI 0.23-3.68) were inconclusive. Type 2 diabetes increased the risk of recurrent MCVE in patients with coronary artery disease, but there is no convincing evidence that it is a major risk factor for subsequent MCVE in all patients with symptomatic vascular disease. © 2015 by the American Diabetes Association. Readers may use this article as long as the work is properly cited, the use is educational and not for profit, and the work is not altered.
    Diabetes care 06/2015; DOI:10.2337/dc14-2900 · 8.57 Impact Factor
  • J Hofmeijer, L J Kappelle, C J M Klijn
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    ABSTRACT: In patients who have intracerebral haemorrhage while on antithrombotic treatment, there is no evidence from randomised clinical trials to support decisions with regard to antithrombotic medication. In the acute phase, we advise stopping all antithrombotic treatment with rapid reversal of antithrombotic effects of oral anticoagulants. After the acute phase, we discourage restarting oral anticoagulants in patients with a lobar haematoma caused by cerebral amyloid angiopathy because of the high risk of recurrent bleeding. In these patients, even treatment with platelet inhibitors needs careful weighing of the risks of bleeding and ischaemic stroke. In patients with non-lobar intracerebral haemorrhage, we suggest considering restarting optimal antithrombotic treatment. This includes treatment with oral anticoagulants for patients with atrial fibrillation and/or mechanical valve prosthesis. After intracerebral haemorrhage during oral anticoagulant therapy in patients with atrial fibrillation, direct anticoagulants may be better than vitamin K antagonists, but we await confirmation of this from ongoing trials. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.
    Practical Neurology 04/2015; DOI:10.1136/practneurol-2015-001104
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    ABSTRACT: Thus far, blood flow velocity measurements with MRI have only been feasible in large cerebral blood vessels. High-field-strength MRI may now permit velocity measurements in much smaller arteries. The aim of this proof of principle study was to measure the blood flow velocity and pulsatility of cerebral perforating arteries with 7-T MRI. A two-dimensional (2D), single-slice quantitative flow (Qflow) sequence was used to measure blood flow velocities during the cardiac cycle in perforating arteries in the basal ganglia (BG) and semioval centre (CSO), from which a mean normalised pulsatility index (PI) per region was calculated (n = 6 human subjects, aged 23–29 years). The precision of the measurements was determined by repeated imaging and performance of a Bland–Altman analysis, and confounding effects of partial volume and noise on the measurements were simulated. The median number of arteries included was 14 in CSO and 19 in BG. In CSO, the average velocity per volunteer was in the range 0.5–1.0 cm/s and PI was 0.24–0.39. In BG, the average velocity was in the range 3.9–5.1 cm/s and PI was 0.51–0.62. Between repeated scans, the precision of the average, maximum and minimum velocity per vessel decreased with the size of the arteries, and was relatively low in CSO and BG compared with the M1 segment of the middle cerebral artery. The precision of PI per region was comparable with that of M1. The simulations proved that velocities can be measured in vessels with a diameter of more than 80 µm, but are underestimated as a result of partial volume effects, whilst pulsatility is overestimated. Blood flow velocity and pulsatility in cerebral perforating arteries have been measured directly in vivo for the first time, with moderate to good precision. This may be an interesting metric for the study of haemodynamic changes in aging and cerebral small vessel disease. © 2015 The Authors NMR in Biomedicine Published by John Wiley & Sons Ltd.
    NMR in Biomedicine 04/2015; DOI:10.1002/nbm.3306 · 3.56 Impact Factor
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    ABSTRACT: Mensen met type 2 diabetes mellitus hebben een verhoogd risico op cognitieve achteruitgang en dementie. De oorzaak van dit verhoogde risico is niet duidelijk. In deze studie hebben we onderzocht wat voor type hersenschade op MRI en welke vasculaire risicofactoren samenhangen met versnelde cognitieve achteruitgang bij ouderen met type 2 diabetes.
    04/2015; 10(1):20-20. DOI:10.1007/s12467-012-0007-1
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    ABSTRACT: The purpose of this study was to assess whether calibrated magnetic resonance imaging (MRI) can identify regional variances in cerebral hemodynamics caused by vascular disease. For this, arterial spin labeling (ASL)/blood oxygen level-dependent (BOLD) MRI was performed in 11 patients (65±7 years) and 14 controls (66±4 years). Cerebral blood flow (CBF), ASL cerebrovascular reactivity (CVR), BOLD CVR, oxygen extraction fraction (OEF), and cerebral metabolic rate of oxygen (CMRO2) were evaluated. The CBF was 34±5 and 36±11 mL/100 g per minute in the ipsilateral middle cerebral artery (MCA) territory of the patients and the controls. Arterial spin labeling CVR was 44±20 and 53±10% per 10 mm Hg ▵EtCO2 in patients and controls. The BOLD CVR was lower in the patients compared with the controls (1.3±0.8 versus 2.2±0.4% per 10 mm Hg ▵EtCO2, P<0.01). The OEF was 41±8% and 38±6%, and the CMRO2 was 116±39 and 111±40 μmol/100 g per minute in the patients and the controls. The BOLD CVR was lower in the ipsilateral than in the contralateral MCA territory of the patients (1.2±0.6 versus 1.6±0.5% per 10 mmHg ▵EtCO2, P<0.01). Analysis was hampered in three patients due to delayed arrival time. Thus, regional hemodynamic impairment was identified with calibrated MRI. Delayed arrival artifacts limited the interpretation of the images in some patients.Journal of Cerebral Blood Flow & Metabolism advance online publication, 25 February 2015; doi:10.1038/jcbfm.2015.14.
    Journal of Cerebral Blood Flow & Metabolism 02/2015; 35(6). DOI:10.1038/jcbfm.2015.14 · 5.34 Impact Factor
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    ABSTRACT: Aneurysms of the extracranial carotid artery (ECAA) are rare. Although most ECAA are identified in asymptomatic patients, serious neurological complications may occur. Current literature on treatment outcome contains mainly case reports and small case series with incomplete data and lack of long--term follow--up. There is clear lack on natural follow--up data, and there is no clear treatment algorithm. An international web--based registry to collect data on patients with ECAA is designed to provide clinical guidance on this scarce pathology. The Carotid Aneurysm Registry (CAR) is open for inclusion of all patients with a fusiform or saccular ECAA. Patients with primary or secondary ECAA can be enrolled in CAR independent of the type of treatment (conservative or invasive). CAR participation does not interfere with the local physician's treatment policy. Follow--up and imaging can also be scheduled according to local clinical practice. The primary endpoint of the CAR in conservative patients is occurrence of symptoms related to the aneurysm at 30 days, one, three, and five years. The primary endpoint in invasively treated patients is freedom from symptoms of the aneurysm at 30 days, one, three, and five years. Analyses will relate outcome to etiology, imaging characteristics, ECAA growth patterns, and (if applicable) revascularization technique applied. The aim of the registry is to prospectively collect follow--up data on patients with an ECAA, being either treated conservatively or by invasive aneurysm exclusion strategies. The CAR database will be used to address diagnostic and therapeutic research questions. Collecting and analyzing the data gained from the registry could be the first step towards development of treatment guidelines and expert consensus for the management of ECAA.
  • D P J Smeeing, L J Kappelle, J Hendrikse
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    ABSTRACT: A 60-year-old woman with a history of hypertension presented with acute onset of left-sided weakness and drowsiness. Non-contrast CT at baseline and follow-up showed a focal high density lesion in the right middle cerebral artery, consistent with a calcified embolus. CT angiography confirmed its location.
    Nederlands tijdschrift voor geneeskunde 01/2015; 159:A8946.
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    ABSTRACT: - There is no evidence from randomised clinical trials with regard to the question if and when to resume antithrombotic medication in patients who have suffered an intracerebral haemorrhage and in whom medication continues to be indicated.- It is unknown whether new oral anticoagulants are more suitable than vitamin K antagonists in this group of patients.- Oral anticoagulants should probably not be resumed in patients with a lobar intracerebral haemorrhage caused by cerebral amyloid angiopathy. They can be considered in patients with a haemorrhage in subcortical regions of the brain, the brain stem or the cerebellum, provided that blood pressure levels are under control. - Depending on the risk of a cardiac embolus, antithrombotic medication can be resumed from 1 to 10 weeks after the intracerebral haemorrhage. In patients with atrial fibrillation this risk can be calculated using the CHA2DS2-VASc score. - In patients with a cardiac indication for antithrombotic medication the decision whether or not to resume medication should be made by a cardiologist and a neurologist in collaboration.
    Nederlands tijdschrift voor geneeskunde 01/2015; 159:A8507.
  • International Journal of Stroke 10/2014; 9:79-80. · 4.03 Impact Factor
  • International Journal of Stroke 10/2014; 9:38-38. · 4.03 Impact Factor
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    ABSTRACT: Endovascular or intra-arterial treatment (IAT) increases the likelihood of recanalization in patients with acute ischemic stroke caused by a proximal intracranial arterial occlusion. However, a beneficial effect of IAT on functional recovery in patients with acute ischemic stroke remains unproven. The aim of this study is to assess the effect of IAT on functional outcome in patients with acute ischemic stroke. Additionally, we aim to assess the safety of IAT, and the effect on recanalization of different mechanical treatment modalities.Methods/design: A multicenter randomized clinical trial with blinded outcome assessment. The active comparison is IAT versus no IAT. IAT may consist of intra-arterial thrombolysis with alteplase or urokinase, mechanical treatment or both. Mechanical treatment refers to retraction, aspiration, sonolysis, or use of a retrievable stent (stent-retriever). Patients with a relevant intracranial proximal arterial occlusion of the anterior circulation, who can be treated within 6 hours after stroke onset, are eligible. Treatment effect will be estimated with ordinal logistic regression (shift analysis); 500 patients will be included in the trial for a power of 80% to detect a shift leading to a decrease in dependency in 10% of treated patients. The primary outcome is the score on the modified Rankin scale at 90 days. Secondary outcomes are the National Institutes of Health stroke scale score at 24 hours, vessel patency at 24 hours, infarct size on day 5, and the occurrence of major bleeding during the first 5 days.
    Trials 09/2014; 15(1):343. DOI:10.1186/1745-6215-15-343 · 2.12 Impact Factor
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    ABSTRACT: Low-grade inflammation and endothelial dysfunction are related to cognitive decline and dementia, in a complex interplay with vascular factors and aging. We investigated, in an older population, low-grade inflammation and endothelial dysfunction in relation to detailed assessment of cognitive functioning. Furthermore, we explored this association within the context of vascular factors. 377 participants (73 ± 6 years) of the population-based Hoorn Study were included. In plasma samples of 2000–2001 (n = 363) and/or 2005–2008 (n = 323), biomarkers were determined of low-grade inflammation (CRP, TNF-alpha, IL-6, IL-8, SAA, MPO, and sICAM-1) and endothelial dysfunction (vWF, sICAM-1, sVCAM-1, sTM, sE-selectin). In 2005–2008, all participants underwent neuropsychological examination. Composite z-scores were computed for low-grade inflammation and endothelial dysfunction at both time points, and for six domains of cognitive functioning (abstract reasoning, memory, information processing speed, attention and executive functioning, visuoconstruction, and language). The association between low-grade inflammation and endothelial dysfunction, and cognitive functioning was evaluated with linear regression analysis. In secondary analyses, we explored the relation with vascular risk factors and cardiovascular disease. Low-grade inflammation and endothelial dysfunction were associated with worse performance on information processing speed and attention and executive functioning, in prospective and cross-sectional analyses (standardized betas ranging from −0.20 to −0.10). No significant relation with other cognitive domains was observed. Adjusting for vascular factors slightly attenuated the associations. Low-grade inflammation and endothelial dysfunction accounted for only 2.6% explained variance in cognitive functioning, on top of related vascular risk factors and cardiovascular disease. Bootstrapping analyses show that low-grade inflammation and endothelial dysfunction mediate the relation between vascular risk factors and cognitive functioning. This study shows that low-grade inflammation and endothelial dysfunction contribute to reduced information processing speed and executive functioning in an older population.
    Psychoneuroendocrinology 02/2014; 40:108–118. DOI:10.1016/j.psyneuen.2013.11.011 · 5.59 Impact Factor
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    ABSTRACT: In patients with recently symptomatic carotid artery stenosis, guidelines recommend carotid revascularization within 2 weeks of the index event. The "index event" may be defined as either the first or the most recent event. The delay between the index event and carotid endarterectomy (CEA) over a period of 6 years in a single centre was evaluated and the effect of defining the index event as either the first or the most recent event was assessed. Observational study. 555 consecutive patients with symptomatic carotid stenosis ≥50% treated with CEA between 2007 and 2012 were assessed. In 2010, changes to the in-hospital process of care to reduce delays in referral and CEA were introduced. These changes included, for example, improving access to physicians, imaging, and operating rooms. The delay from symptoms to surgery was expressed in days. The median time between the first event and surgery was reduced from 53 days (interquartile range [IQR] 30-78) in 2007 to 21 days (IQR 12-45) in 2012, and between the most recent event and CEA from 45 days (IQR 28-67) to 17 days (IQR 9-28). Patients referred directly by their general practitioner more often underwent CEA within 2 weeks than patients referred by specialists from other hospitals. Compared to patients with transient ischaemic attack or ocular symptoms, patients with ischaemic stroke more often underwent CEA within 2 weeks. A small change in the process of care significantly reduced the delay from the index event to CEA, but in 2012 it still exceeded 14 days in the majority of patients. The definition of the "index event" has a large impact on the total duration of delay, and should therefore be uniform across studies.
    European journal of vascular and endovascular surgery: the official journal of the European Society for Vascular Surgery 01/2014; 47(3). DOI:10.1016/j.ejvs.2013.12.013 · 3.07 Impact Factor
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    ABSTRACT: Background: In stroke erythrocyte-rich thrombi are more sensitive to intravenous thrombolysis with recombinant tissue plasminogen activator (IV-rtPA) and have higher density on non-contrast CT (NCCT). We investigated the relationship between thrombus density and recanalization and whether persistent occlusions can be predicted by Hounsfield unit (HU) measurements. Methods: In 88 IV-rtPA-treated patients with intracranial ICA or MCA occluding thrombus and follow-up imaging, thrombus and contralateral vessel attenuation measurements were performed on thin-slice NCCT. Mean absolute and relative HU were compared between patients with persistent occlusion (modified Thrombolysis in Cerebral Infarction system, grade 0/1/2a) and recanalization (grade 2b/3). Univariate and multivariate (adjusted for stroke subtype, clot burden score, occlusion site and time to thrombolysis) odds ratios for persistent occlusion were calculated. Additional prognostic value for persistent occlusion was estimated by adding HU measurements to the area under the curve (AUC) of known determinants and calculating optimal cut-off values. Results: Patients with persistent occlusion (n = 19) had significant lower mean HU (absolute 52.2 ± 9.5, relative 1.29 ± 0.20) compared to recanalization (absolute 63.1 ± 10.7, relative 1.54 ± 0.23, both p < 0.0001). Odds ratios for persistent occlusion were 3.1 (95% confidence interval, CI 1.6-6.0) univariate and 3.1 (95% CI 1.7-5.7) multivariate per 10 absolute HU decrease and 3.2 (95% CI 1.6-6.5) univariate and 4.1 (95% CI 1.8-9.1) multivariate per 0.20 relative HU decrease. Attenuation measurements significantly increased the AUC (0.67) of the known determinants to 0.84 (absolute HU) and 0.86 (relative HU). Cut-off values of <56.5 absolute HU and <1.38 relative HU showed optimal predictive values for persistent occlusion. Conclusions: Thrombus density is related to recanalization rate. Lower absolute and relative HU are independently related to persistent occlusion and HU measurements significantly increase discriminative performances of known recanalization determinants. © 2014 S. Karger AG, Basel.
    Cerebrovascular Diseases 01/2014; 37(2):116-122. DOI:10.1159/000357420 · 3.70 Impact Factor
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    ABSTRACT: Patients with symptomatic carotid artery stenosis are at high risk for recurrent stroke. To date, the decision to perform carotid endarterectomy in patients with a recent cerebrovascular event is mainly based on degree of stenosis of the ipsilateral carotid artery. However, additional atherosclerotic plaque characteristics might be better predictors of stroke, allowing for more precise selection of patients for carotid endarterectomy. We investigate the hypothesis that the assessment of carotid plaque characteristics with magnetic resonance imaging, multidetector-row computed tomography angiography, ultrasonography, and transcranial Doppler, either alone or in combination, may improve identification of a subgroup of patients with < 70% carotid artery stenosis with an increased risk of recurrent stroke. The Plaque At RISK (PARISK) study is a prospective multicenter cohort study of patients with recent (<3 months) neurological symptoms due to ischemia in the territory of the carotid artery and < 70% ipsilateral carotid artery stenosis who are not scheduled for carotid endarterectomy or stenting. At baseline, 300 patients will undergo magnetic resonance imaging, multidetector-row computed tomography angiography, and ultrasonography examination of the carotid arteries. In addition, magnetic resonance imaging of the brain, ambulatory transcranial Doppler recording of the middle cerebral artery and blood withdrawal will be performed. After two-years, imaging will be repeated in 150 patients. All patients undergo a follow-up brain magnetic resonance imaging, and there will be regular clinical follow-up until the end of the study. The combined primary end-point contains ipsilateral recurrent ischemic stroke or transient ischemic attack or new ipsilateral ischemic brain lesions on follow-up brain magnetic resonance imaging.
    International Journal of Stroke 10/2013; 9(6). DOI:10.1111/ijs.12167 · 4.03 Impact Factor
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    ABSTRACT: The occurrence of cerebral ischemia during carotid endarterectomy (CEA) can be prevented by (selective) placement of an intraluminal shunt during cross-clamping. We set out to develop a rule to predict the likelihood for shunting during CEA based on preoperative assessment of collateral cerebral circulation and patient characteristics. Patients who underwent CEA between 2004 and 2010 were included. Patients without preoperative magnetic resonance (MRA) or computed tomography angiography (CTA) were excluded. The primary endpoint was intraluminal shunt placement based on electroencephalography changes. Age, sex, cardiovascular risk factors peripheral artery disease, symptomatic status, degree of ipsilateral and contralateral carotid, status of the vertebral arteries, and morphology of the CoW were studied as potential predictors for shunt use. A prediction model was derived from a multivariable regression model using discrimination, calibration, and bootstrapping approaches and transformed into a clinical prediction model. A total of 431 patients were included, of which 65 patients (15%) received an intraluminal shunt. In the MRA group (n = 285) factors related to shunt use in multivariate analysis were ipsilateral carotid stenosis 90-99% (odds ratio [OR] 0.15, 95% CI 0.04-0.53), contralateral carotid occlusion (OR 4.29, 95% CI 1.68-10.95) and any not-visible anterior (OR 4.96, 95% CI 1.95-12.58) or ipsilateral posterior segment of the CoW (OR 5.08, 95% CI 2.10-12.32). In the CT group none of the factors were independently related to shunt use; therefore, only predictors describing morphology of CoW derived from MRA findings were included in our model. The c-statistic of this model was 0.79 (95% CI 0.72-0.86). Among patients with an estimated chance of needing a shunt of under 10% (49% of the population), the likelihood of shunting was 5%. In those in whom this chance was estimated higher than 30% (13% of the population) the likelihood was 51%. Among patients scheduled for CEA, assessment of cerebral arteries and of the configuration of the CoW based on MRA-derived images can help to identify patients with low and high likelihood of the need of shunt use during surgery.
    European journal of vascular and endovascular surgery: the official journal of the European Society for Vascular Surgery 09/2013; 46(6). DOI:10.1016/j.ejvs.2013.09.007 · 3.07 Impact Factor
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    ABSTRACT: This study assessed the value of cerebral near-infrared spectroscopy (NIRS) and transcranial Doppler (TCD) in relation to electroencephalography (EEG) changes for the detection of cerebral hypoperfusion necessitating shunt placement during carotid endarterectomy (CEA). This was a prospective cohort study. Patients with a sufficient TCD window undergoing CEA from February 2009 to June 2011 were included. All patients were continuously monitored with NIRS and EEG. An intraluminal shunt was placed, selectively determined by predefined EEG changes in alpha, beta, theta, or delta activity. Relative changes in regional cerebral oxygen saturation (rSO2) in the frontal lobe and mean blood flow velocity (Vmean) 30 seconds before carotid cross-clamping versus 2 minutes after carotid cross-clamping were related to shunt placement. Receiver operating characteristic curve analysis was performed to determine the optimal thresholds. Diagnostic values were reported as positive and negative predictive value (PPV and NPV). Of a cohort of 151 patients, 17(11%) showed EEG changes requiring shunt placement. The rSO2 and Vmean decreased more in the shunt group than in the non-shunt group (mean ± standard error of the mean) 21 ± 4% versus 7 ± 5% and 76 ± 6% versus 12 ± 3%, respectively (p < .005), Receiver operating characteristic curve analysis revealed a threshold of 16% decrease in rSO2 (PPV 76% and NPV 99%) and 48% decrease in Vmean (PPV 53% and NPV 99%) as the optimal cut-off value to detect cerebral ischemia during CEA under general anesthesia. Compared with EEG, we found moderate PPV but high NPV for NIRS and TCD to detect cerebral ischemia during CEA under general anesthesia, meaning that both techniques independently may be suitable to exclude patients for unnecessary shunt use and to direct the use of selective shunting. However, the optimal thresholds for NIRS remain to be determined.
    European journal of vascular and endovascular surgery: the official journal of the European Society for Vascular Surgery 08/2013; 46(4). DOI:10.1016/j.ejvs.2013.07.007 · 3.07 Impact Factor
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    ABSTRACT: To study the association between the epsilon 4 allele of apolipoprotein E (APOEε4) and delirium in a stroke population. 527 consecutive stroke patients were screened for delirium during the first week of admission with the confusion assessment method. In three hundred fifty-three patients genomic DNA isolation was available. The incidence of delirium after stroke in the 353 patients was 11.3%. There was no association between APOEε4 and delirium. Even after adjustment for IQCODE, stroke localization, stroke subtype, stroke severity, infection, and brain atrophy no association was found (odds ratio: 0.9; 95% confidence interval: 0.4-2.1). Delirium did not last longer in patients with an APOEε4 allele compared to patients without an APOEε4 allele (median: 5.6 days [range: 1-21] versus median: 4.6 days [range: 1-15], p = 0.5). There was no association between the presence of an APOEε4 allele and the occurrence of delirium in the acute phase after stroke.
    The American journal of geriatric psychiatry: official journal of the American Association for Geriatric Psychiatry 08/2013; 21(10). DOI:10.1016/j.jagp.2013.01.068 · 3.52 Impact Factor

Publication Stats

10k Citations
1,359.12 Total Impact Points

Institutions

  • 1986–2015
    • University Medical Center Utrecht
      • Department of Neurology
      Utrecht, Utrecht, Netherlands
  • 1991–2013
    • Universiteit Utrecht
      • • Division of Experimental Psychology
      • • Department of Neurology
      • • Department of Radiology
      Utrecht, Utrecht, Netherlands
  • 2009
    • Baylor College of Medicine
      • Department of Neurology
      Houston, Texas, United States
  • 2003
    • Erasmus MC
      • Department of Neurology
      Rotterdam, South Holland, Netherlands
  • 2002
    • Hennepin County Medical Center
      Minneapolis, Minnesota, United States
  • 1993
    • University of Texas Health Science Center at San Antonio
      San Antonio, Texas, United States