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L J Kappelle

Publications and source records attributed to L J Kappelle.

At least 19 recordsLinked to original sources
PubMed2000

Recurrent ischemia in symptomatic carotid occlusion: prognostic value of hemodynamic factors.

OBJECTIVE: To identify hemodynamic factors that predict recurrence of ipsilateral cerebral ischemic events in patients with symptomatic carotid artery occlusion (CAO). PATIENTS AND METHODS: The authors studied 117 consecutive patients with CAO and corresponding recent (</=6 months) ischemic symptoms of the brain or eye that were transient or at most mildly disabling. They determined, using Cox proportional hazards analysis, the prognostic value for recurrence of ipsilateral cerebral ischemic events of 1) clinical features believed to indicate hemodynamic compromise, 2) collateral blood flow pattern, and 3) transcranial Doppler CO(2)-reactivity. RESULTS: None of the 24 patients with symptoms of retinal ischemia alone had a recurrent cerebral ischemic event. In the 93 patients with cerebral ischemic symptoms on entry, recurrence of these symptoms was independently predicted by 1) the nature of the initial symptoms being of purported hemodynamic origin (limb-shaking, precipitation of symptoms by rising, exercise or low blood pressure, retinal claudication) (hazard ratio [HR] 3.8, 95% CI 1.5 to 9.5), 2) continuing symptoms after the CAO had been documented, but before inclusion in the study (HR 5.9, 95% CI 2.2 to 16.1), and 3) the presence of collateral blood flow via leptomeningeal vessels (HR 4.1, 95% CI 1.3 to 13.1). CO(2)-reactivity did not predict recurrence of cerebral ischemic events. CONCLUSIONS: Having cerebral in contrast to retinal ischemia, clinical features suggestive of hemodynamic compromise, continuing symptoms after demonstration of the CAO, and presence of leptomeningeal collaterals may help to identify patients with symptomatic CAO at high risk of future cerebral ischemia.

Aged↗
PubMed2000

Small, unruptured intracranial aneurysms and management of symptomatic carotid artery stenosis. North American Symptomatic Carotid Endarterectomy Trial Group.

Of the 2885 patients participating in the North American Symptomatic Carotid Endarterectomy Trial, 90 (3.1%) had unruptured intracranial aneurysms (UIA), of which 96% had a diameter of less than 10 mm. During an average 5-year follow-up, only one patient had subarachnoid hemorrhage 6 days after carotid endarterectomy (CE). For patients with unrepaired UIA, the 5-year stroke risk was 10% after CE and 22.7% with best medical care. Both risks are similar to those of patients without UIA. The decision regarding CE probably should not be influenced by the presence of a small UIA.

Aged↗
PubMed2000

[Intravenous thrombolytic therapy: ideal treatment for acute ischemic stroke].

In four patients with symptoms of presumed acute ischaemic stroke intravenous treatment with recombinant tissue plasminogen activator (rtPA) was considered. Two patients indeed received rtPA within 3 hours after onset of symptoms. One of them, a 55-year-old woman, recovered and was able to resume her job as a teacher four months later. The other patient, a 38-year-old man, had a severe bleeding complication that could be stopped, but the patient died several days later because of the massive stroke. The third patient, an 82-year-old woman, could not be treated with rtPA because the time of onset of neurological deficit was uncertain. Nevertheless, she recovered well from her hemiplegia after a few days. The fourth patient, a 24-year-old woman, did not receive rtPA because her symptoms were thought to be the result of a psychogenic disorder. Intravenous thrombolysis increases the risk of intracranial haemorrhage, but should be considered a useful treatment for ischaemic stroke provided there is no doubt about this diagnosis and treatment with rtPA can be started within 3 hours of onset of the neurological deficit.

Acute Disease↗
PubMed2000

[Thrombolytic therapy of brain infarct: the end of beginning].

Thrombolysis by intravenous application of thrombolytic drugs may improve the outcome of patients with a brain infarct, but it also entails risks. The effect of recombinant tissue plasminogen activator (rtPA) was compared with placebo in three medium-sized randomized controlled clinical trials. One study, performed in North America, showed a clear benefit of rtPA administered within 3 hours after the onset of symptoms. Two European trials showed a less strong effect, but the number of patients who were independent after 3 months' follow-up was also larger after treatment with rtPA within 6 hours. A meta-analysis of all three trials demonstrates a significant advantage of rtPA over placebo for all the usual outcome measures, without significant excess mortality in the rtPA group. The chance of being able to live independently increases by about 8% after treatment with rtPA. In conclusion there is now sufficient evidence to start with thrombolytic treatment for cerebral infarcts in hospitals with a stroke unit, if a number of additional quality standards for the acute diagnosis and treatment of stroke patients are met.

Acute Disease↗
PubMed2000

Cerebral metabolic changes in patients with a symptomatic occlusion of the internal carotid artery: a longitudinal 1H magnetic resonance spectroscopy study.

The objective of this 1H magnetic resonance spectroscopy study was to investigate the time course of the brain metabolites N-acetyl-aspartate (NAA), choline, and lactate in patients with transient or minor disabling neurological deficits associated with an occlusion of the internal carotid artery (ICA). Fifty patients had had symptoms of hemispheric ischemia, and 16 had suffered symptoms of retinal ischemia. Single-voxel proton spectra were obtained from uninfarcted cerebral regions on three occasions: 0-6, 6-12, and 12-18 months after symptoms. Reference values were obtained from 29 control subjects. In the 0-6 month period, patients with hemispheric ischemia showed a significantly lower NAA/creatine ratio in the hemisphere ipsilateral to the ICA occlusion, compared with control subjects and patients with retinal ischemia, and a significantly higher choline/creatine ratio, compared with control subjects. The prevalence of lactate did not differ significantly between patient groups. In the following time periods, the NAA/creatine ratio in patients with hemispheric ischemia tended to return to control values and no longer differed from that in patients with retinal ischemia; the choline/creatine ratio decreased significantly and returned to control values. These results demonstrate that cerebral metabolism is altered in patients with an ICA occlusion who have had a hemispheric ischemic event, but returns (choline) or tends to return (NAA) to control values over time. The metabolic changes occur primarily in the hemisphere ipsilateral to the symptomatic ICA occlusion and are related to the occurrence of the hemispheric ischemic event.

Aged↗
PubMed2000

Prognostic value of perfusion- and diffusion-weighted MR imaging in first 3 days of stroke.

The aim of this study was to evaluate the differences in cerebral perfusion seen on mean transit time (MTT) and cerebral blood volume (CBV) maps and to assess the subsequent prognostic value of the MTT-DWI (diffusion-weighted MRI) and CBV-DWI mismatch in the first three days of stroke on lesion enlargement and clinical outcome. In 38 patients, imaged 1-46 h after onset of symptoms, lesion volumes on proton-density (PD)-weighted MRI, DWI and PWI (both MTT and CBV maps) were compared with lesion volumes on follow-up PD-weighted scans, and to clinical outcome (National Institutes of Health Stroke Scale, Barthel index, and Rankin scale). The MTT-CBV, MTT-DWI and CBV-DWI mismatches were compared with change in lesion volume between initial and follow-up PD-weighted scans. Lesion volume on both DWI and PWI correlated significantly with clinical outcome parameters (p < 0.001) with strongest correlation for lesion volume on CBV. Perfusion-diffusion mismatches were found for both CBV and MTT and correlated significantly with lesion enlargement on PDweighted imaging with strongest correlation for the CBV-DWI mismatch. The CBV-DWI mismatch has the highest accuracy in predicting lesion size on follow-up imaging and in predicting clinical outcome. Lesion volume measurements on CBV maps have a higher specificity than on PD-weighted, MTT or DWI images in predicting clinical follow-up imaging and in predicting clinical outcome.

Adult↗
PubMed2000

Cognitive disorders in patients with occlusive disease of the carotid artery: a systematic review of the literature.

We present a systematic review of the literature on the prevalence, nature, severity, course, and causes of cognitive deficits in patients with occlusive disease of the carotid artery prior to surgery (if surgery was under discussion). Searches were carried out on Medline and Psychlit from 1980 to 1999 using neurovascular and psychological index terms, and papers and books were checked for further references. Studies describing neuropsychological assessment of groups of patients with carotid obstruction were included. Eighteen studies were found. We extracted from the papers data on study design, demographic characteristics of patients, clinical diagnosis, carotid obstruction, cerebral imaging, time interval between ischemic episode and neuropsychological assessment, neuropsychological assessment procedures, integration and interpretation of test performances, and conclusions of authors. Fourteen studies concluded that there are cognitive deficits both in patients with symptomatic and in those with asymptomatic carotid obstruction; four studies denied cognitive impairment. There were no differences in patient characteristics, study design, or neuropsychological assessment procedures between the 14 studies that found deficits and the 4 that did not. There are indications for a mild, diffuse detrimental effect of carotid occlusive disease on cognitive functioning. However, methodological problems prevent a definitive conclusion. Further research is needed to confirm these findings and to ascertain the neurovascular risk factors for and the natural course of cognitive impairment in patients with carotid occlusive disease.

Adult↗
PubMed2000

Prognosis of ischemic stroke in childhood: a long-term follow-up study.

Little is known about long-term physical sequelae, cognitive functioning, and quality of life in children who have experienced ischemic stroke. Thirty-seven patients under 16 years of age were studied; the median interval after stroke was 7 years. CT-scans were reassessed to determine the type of infarction at baseline. Occurrences of death, of new cardiovascular events, and of seizures during follow-up were recorded. Surviving patients were invited for a follow-up examination, including physical check-up, global screening of cognition, and an inventory of subjective health perception. Only two patients were lost to follow-up. During follow-up four died, nine developed seizures, eight had transient ischemic attacks, and two experienced a recurrent ischemic stroke. None of the patients had cardiac complications during follow-up. In 11 of 27, no functional impairment was found, in 15 there was a hemiparesis of varying severity, and in one a paraplegia. There was a significant shift in cognitive functioning towards lower levels, especially in children with epilepsy. Remedial teaching was frequently needed. Many of the parents' perceived their child's behavior to be very changeable. Three-quarters of the children considered themselves as healthy as other children, and almost all of them as happy. The physical and functional prognosis after ischemic stroke in childhood is relatively good, particularly in children with no serious causative illness, but special education is often needed and social changes occur.

Adolescent↗
PubMed2000

Outcome in patients with symptomatic occlusion of the internal carotid artery.

OBJECTIVES: to assess whether the risk of recurrent ischaemic stroke in patients with symptomatic internal carotid artery (ICA) occlusion has changed over the past decades, to determine risk factors for the occurrence of ischaemic stroke and to assess the risk of endarterectomy (CEA) of a severe contralateral ICA stenosis. DESIGN: retrospective cohort study. PATIENTS AND METHODS: patients with symptomatic ICA occlusion were identified from duplex registry files between 1991 and 1995. Information was obtained on vascular risk factors, performance of CEA for a contralateral ICA stenosis and on recurrence of ischaemic stroke. The rate of complications occurring within 30 days after CEA of the contralateral ICA in patients with symptomatic ICA occlusion was compared with the risk of CEA in patients with asymptomatic ICA occlusion and severe contralateral ICA stenosis (symptomatic or asymptomatic). RESULTS: ninety-seven patients were identified. Mean follow-up time was 26 months. The annual risk of (non-)fatal stroke was 5.3% for all strokes (95% CI 2. 9%-9.6%) and 3.8% for ipsilateral stroke (95% CI 1.9%-7.7%). Hyperlipidaemia and severe stenosis of the contralateral ICA were independent risk factors. Twenty-two of 32 patients with a severe stenosis of the contralateral ICA underwent CEA, of which one patient died and three suffered a minor ischaemic stroke. The perioperative risk of CEA in the control group of 20 patients with asymptomatic contralateral ICA occlusion was 0% (0 of 20). CONCLUSIONS: outcome in patients with symptomatic ICA occlusion has not substantially improved over the years. CEA for severe stenosis of the contralateral ICA carried a relatively high risk in our series, but deserves to be studied in a controlled design.

Adult↗
PubMed2000

Cerebral ischaemic changes in association with the severity of ICA lesions and cerebropetal flow.

OBJECTIVES: To study the effect of the severity of internal carotid artery (ICA) lesions on cerebral haemodynamics. DESIGN: Cross-sectional study. MATERIALS AND METHODS: Magnetic resonance (MR) imaging, angiography (MRA) and spectroscopy (MRS) were used to study the prevalence of (border-zone) infarctions, volume flow in the main cerebropetal and middle cerebral arteries (MCA) and metabolic changes in the MCA territories in 170 patients with symptomatic ICA stenoses or occlusions and 25 control subjects. RESULTS: No significant correlation was found between severity of the carotid lesion and the prevalence of border-zone infarctions. Also, no significant correlation was found with changes in the N -acetyl-aspartate/choline ratio nor with the prevalence of cerebral lactate. In patients with at least one severe ICA lesion, flow in the basilar artery was increased. Flow in the MCA on the symptomatic and asymptomatic side was decreased when at least one ICA was occluded. Total cerebropetal flow (flow through the ICAs plus basilar artery) was decreased when at least one ICA was occluded. No significant correlation was found between changes in cerebropetal flow and the N -acetyl-aspartate/choline ratio nor with the prevalence of border-zone infarctions. CONCLUSION: Border-zone infarctions and ischaemic metabolic changes are not directly the result of cerebral hypoperfusion caused by severe ICA lesions.

Aged↗
PubMed2000

Spatial memory impairment in patients after tumour resection: evidence for a double dissociation.

Human spatial memory can be divided into multiple, partly separate cognitive processes. In this study, object location memory was studied using a set of tasks that assessed three different spatial memory aspects: positional memory, object location binding, and a combined process. Also, maze learning and spatial span memory were measured. Ten patients who had undergone intracranial tumour resection participated, and their individual results were compared with control data from 24 healthy subjects. Four patients showed selective spatial memory impairments; two patients were impaired at positional memory, and two other patients were impaired on object location binding and the combined process. This double dissociation provides further evidence for the notion that object location memory is not a unitary system, but consists of at least two separate mechanisms. In addition, spatial memory problems were predominantly present in the patients with lesions in either the right hemisphere or in the parietal lobe. These results are in agreement with previous findings on the involvement of the right hemisphere and the posterior parietal cortices in spatial processing.

Adult↗
PubMed2000

Magnetic resonance techniques for the identification of patients with symptomatic carotid artery occlusion at high risk of cerebral ischemic events.

BACKGROUND AND PURPOSE: We sought to assess whether MRI, MR angiography, or (1)H MR spectroscopy can be used to identify patients with symptomatic carotid artery occlusion (CAO) who are at high risk of recurrent ipsilateral cerebral ischemic events. METHODS: In 115 consecutive patients with transient or moderately disabling symptoms of cerebral or retinal ischemia and ipsilateral CAO, we studied the prognostic value of (1) presence of a border-zone infarct; (2) quantitative flow in the middle cerebral artery (MCA) ipsilateral to the CAO; and (3) metabolic ratios in the centrum semiovale ipsilateral to the CAO. RESULTS: Presence of a border-zone infarct and the rate of flow in the MCA did not have a significant relationship with recurrence of cerebral ischemic events. Patients with a low N:-acetyl aspartate (NAA)/choline ratio had an annual risk of recurrent, ipsilateral, cerebral ischemic events of 16.0% (95% CI, 9.5 to 27.0), whereas this risk was 4.2% (95% CI, 2.2 to 8.0) in those with a normal NAA/choline ratio (hazard ratio, 0. 43; 95% CI, 0.19 to 1.00). Patients who on entry had had only retinal symptoms had on average a higher NAA/choline ratio (mean difference, 0.25; 95% CI, 0.13 to 0.37) and a lower risk of recurrent cerebral ischemic events (odds ratio, 0.0; 95% CI, 0.0 to 0.6) than those with cerebral ischemic symptoms. CONCLUSIONS: NAA/choline ratio measured by (1)H MRS, but not the presence of a border-zone infarct or the amount of flow in the MCA, can identify patients with symptomatic CAO who are at risk of future ipsilateral cerebral ischemic events.

Adult↗
PubMed2000

A longitudinal study of collateral flow patterns in the circle of Willis and the ophthalmic artery in patients with a symptomatic internal carotid artery occlusion.

BACKGROUND AND PURPOSE: The purpose of the present study was to assess whether the direction of flow via the circle of Willis and the ophthalmic artery (OphA) changed over time in patients with a symptomatic occlusion of the internal carotid artery (ICA) who did not experience recurrent cerebral ischemic symptoms. METHODS: Sixty-two patients with a symptomatic ICA occlusion were investigated within 6 months after symptoms occurred. The investigations were repeated after 6 and 12 months. The directions of flow in the A1 segment and the posterior communicating artery (PCoA), both on the side of the symptomatic ICA occlusion, were assessed with the use of magnetic resonance angiography. The pattern of collateral flow via the circle of Willis was categorized as via the A1 segment only, via the PCoA only, via the A1 segment plus the PCoA, or no collateral flow via the circle of Willis. The direction of flow in the OphA was investigated with transcranial Doppler sonography. CO(2) reactivity was determined with transcranial Doppler sonography to investigate whether changes in flow patterns were accompanied by changes in cerebrovascular reactivity. RESULTS: There were no statistically significant changes over time in the direction of blood flow in the A1 segment and the PCoA or in the pattern of collateral flow via the circle of Willis. On average, 72% of patients with a unilateral ICA occlusion (n=41) had willisian collateral flow compared with 37% of patients with a bilateral ICA occlusion (n=21; P<0.05). Patients with a unilateral ICA occlusion tended to a lower prevalence of reversed flow via the OphA over time. CO(2) reactivity did not change significantly in any patient group. In patients with a unilateral ICA occlusion, decreased CO(2) reactivity was associated with a higher prevalence of absent willisian collateral flow and a lower prevalence of collateral flow via the A1 segment plus the PCoA. CONCLUSIONS: The absence of recurrent cerebral ischemic symptoms in patients with a symptomatic ICA occlusion is not associated with an improvement in collateral flow via the circle of Willis or the OphA during 1.5-year follow-up.

Blood Gas Analysis↗
PubMed2000

Long-term clinical and angiographic outcomes in symptomatic patients with 70% to 99% carotid artery stenosis.

BACKGROUND AND PURPOSE: In 1991, the North American Symptomatic Carotid Endarterectomy Trial (NASCET) reported the benefit of carotid endarterectomy for 659 patients with 70% to 99% stenosis. Follow-up continued until 1997. METHODS: The present study examined the risks and causes of ipsilateral stroke in the randomized groups and in those who had delayed endarterectomy or continued on medical therapy and also examined the evolution of carotid disease on follow-up imaging. RESULTS: By on-treatment (efficacy) analysis, the risk of any ipsilateral stroke at 3 years was 28.3% for medically randomized and 8.9% for surgically randomized patients (19.4% absolute risk reduction, P:<0.001). For combined disabling or fatal ipsilateral stroke, the risks were 14.0% and 3.4%, respectively (10. 6% absolute risk reduction). In medical patients, >80% of the first strokes at 3 years were of large-artery origin. After February 1991, 116 suitable medical patients underwent endarterectomy within 6 months, and 115 continued on medical therapy. The 3-year risk of any ipsilateral stroke in the groups of 116 and 115 patients was 7.9% and 15.0%, respectively (7.1% absolute risk reduction). During follow-up, 81 patients had angiograms comparable to the baseline images. Progression by >/=10% occurred in 7 patients; regression, in 8; no change, in 39; and occlusion, in 27. By use of both angiography and ultrasound, 63 (25.5%) of the 247 medically treated patients progressed to occlusion, of whom 31.7% had an ipsilateral stroke before or on the day of occlusion. CONCLUSIONS: Endarterectomy for patients with 70% to 99% stenosis and recent symptoms was efficacious in the long term. Compared with patients who continued on medical therapy, medical patients with delayed endarterectomy experienced a moderate benefit. Medically treated patients experienced a high risk of occlusion.

Aged↗
PubMed1999

[Creative mathematics with clopidogrel; exaggeration of the preventive effect by manufacturer].

A number of Dutch medical journals recently carried an advertisement stating that clopidogrel treatment reduced the number of ischaemic complications with 26%, compared with aspirin treatment. This is a miscalculation: the actual reduction is 0.51% in absolute rates, and 8.7% in relative terms. The error by Sanofi-Synthelabo arose by comparison of the event rates for clopidogrel (5.32%) as well as for aspirin (5.83%) with that in an imaginary placebo group (7.77%), yielding a reduction of ischaemic complications of 2.45% and 1.94% respectively; erroneous comparison of these two numbers leads to a difference of 26%.

Advertising↗
PubMed1999

[High-flow transcranial bypass for prevention of brain ischemia].

In patients in whom the internal carotid artery has to be occluded because of the presence of an intracranial giant aneurysm or an infiltrating skull base tumour and in patients with brain ischaemia, whose internal carotid artery has been occluded spontaneously on the basis of atherosclerosis, a transcranial bypass can be created. Since the beginning of the seventies 'low-flow bypasses' are made in which a branch of the superficial temporal artery is connected with a cortical branch of the middle cerebral artery. Because of the small calibre of the blood vessels involved the desired effect on the brain circulation is limited. Thanks to the nonocclusive Excimer laser-assisted anastomosing technique, developed by Tulleken et al. in the last fifteen years, it is now possible to create a high-flow bypass in a safe way. A donor vessel, e.g. the V. saphena magna, is connected at one end to the external carotid artery and at the other to the intracranial part of the internal carotid artery beyond the pathological lesion. The mean flow through the bypass was 140 ml/min in about 90 patients. For example, in three patients, a woman aged 45 with rightsided progressive ophthalmoplegia due to a giant aneurysm, a woman aged 31 years with an aneurysm in the right middle ear and a man with a chemodectoma at the base of the skull, a transcranial high-flow bypass was created nonocclusively, after which the internal carotid artery was closed without any problems.

Adult↗