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J van Gijn

Publications and source records attributed to J van Gijn.

At least 181 records · Page 10Linked to original sources
PubMed1995

The Babinski reflex.

The plantar response is a reflex that involves not only the toes, but all muscles that shorten the leg. In the newborn the synergy is brisk, involving all flexor muscles of the leg; these include the toe 'extensors', which also shorten the leg on contraction and therefore are flexors in a physiological sense. As the nervous system matures and the pyramidal tract gains more control over spinal motoneurones the flexion synergy becomes less brisk, and the toe 'extensors' are no longer part of it. The toes then often go down instead of up, as a result of a segmental reflex involving the small foot muscles and the overlying skin, comparable to the abdominal reflexes. With lesions of the pyramidal system, structural or functional, this segmental, downward response of the toes disappears, the flexion synergy may become disinhibited and the extensor hallucis longus muscle is again recruited into the flexion reflex of the leg: the sign of Babinski. A true Babinski sign denotes dysfunction of the pyramidal tract, and should be clearly distinguished from upgoing toes that do not belong to the flexion synergy of the leg. Correct interpretation of the plantar response depends only to a minor degree on the method or site of stimulation of the foot. It is therefore most important to assess the response in the entire leg.

Humans↗
PubMed1995

Detection of cerebral microemboli by means of transcranial Doppler monitoring before and after carotid endarterectomy.

BACKGROUND AND PURPOSE: The main purpose of carotid endarterectomy (CEA) for neurologically symptomatic high-grade extracranial carotid artery stenosis is to remove the suspected source of cerebral microemboli. Transcranial Doppler (TCD) ultrasonography has the potential for detecting solid microemboli in the basal cerebral arteries. Therefore, TCD monitoring provides the opportunity to assess the rate of microemboli to the brain in patients with symptomatic high-grade carotid artery stenosis and to verify whether these phenomena have ceased after CEA. METHODS: TCD monitoring was performed in 41 patients to detect high-intensity transient signals indicating microemboli in the middle cerebral artery before and after CEA. In the event that, within 1 week after CEA, TCD monitoring revealed ongoing cerebral microemboli on the side of surgery, the examination was repeated 3 months later. RESULTS: High-intensity transient signals were detected preoperatively on the side of the affected carotid artery in 22 patients (54%; mean, 10.2 per hour; range, 1 to 88). Linear regression analysis demonstrated a trend toward an inverse relationship between the number of high-intensity transient signals per hour and the time interval since the last episode of neurological symptoms (P < .1). CEA resulted in a significant reduction in the number of high-intensity transient signals per hour 7 days after surgery (mean, 6.0 versus 0.4 per hour; median, 0 versus 0; n = 37; P < .005) and 3 months later (mean, 6.3 versus 0 per hour; median, 1.3 versus 0; n = 41; P < .0001). CONCLUSIONS: Clearly, TCD monitoring can be helpful in assessing the effect of CEA in removing the suspected source of cerebral microemboli. Ongoing microemboli to the brain should prompt reassessment of the operated carotid artery or a search for other potential sources of cerebral embolism. Carotid artery plaques seem to produce cerebral microemboli for a limited period, which implies that the prophylactic effect of CEA might decrease if the operation is delayed.

Adult↗
PubMed1995

Predictors of major vascular events in patients with a transient ischemic attack or minor ischemic stroke and with nonrheumatic atrial fibrillation. European Atrial Fibrillation Trial (EAFT) Study Group.

BACKGROUND AND PURPOSE: The risk of major vascular events after an initial episode of cerebral ischemia in patients with nonrheumatic atrial fibrillation (NRAF) varies from 2% to 15% in the first year and is approximately 5% yearly thereafter. Few studies have reported on risk factors that can be used to identify high-risk subgroups within this patient population. METHODS: We studied the predictive value of several easily obtainable clinical characteristics in a group of 375 placebo-treated patients with NRAF and a recent episode of transient or nondisabling cerebral ischemia who were entered in a multicenter clinical trial. The mean follow-up was 1.6 years. RESULTS: By means of multivariate modeling, six independent variables were identified: history of previous thromboembolism, ischemic heart disease, enlarged cardiothoracic ratio on chest roentgenogram, systolic blood pressure greater than 160 mm Hg at study entry, NRAF for more than 1 year, and presence of an ischemic lesion on CT scan. These variables could also be used to stratify patients in low-, medium-, and high-risk subgroups for the other two arms of the trial, those treated with anticoagulation and aspirin. Patients older than 75 years with three or more risk factors seemingly benefited less from both aspirin and anticoagulant treatment. CONCLUSIONS: Easily obtainable patient characteristics are helpful in estimating the potential effect of adequate secondary prevention in patients with NRAF who recently suffered a transient ischemic attack or minor ischemic stroke.

Aged↗
PubMed1995

Outcome in familial subarachnoid hemorrhage.

BACKGROUND AND PURPOSE: The outcome of subarachnoid hemorrhage in patients with familial occurrence of subarachnoid hemorrhage (familial SAH) is an important but neglected factor in balancing the risks of screening for asymptomatic aneurysms and repairing these in unaffected members of such families. METHODS: We studied the outcome of familial SAH in a prospective, hospital-based series of patients with at least one first-degree relative with SAH and compared it with the outcome in a prospectively collected hospital series of patients selected for the absence of SAH in first- and second-degree relatives. Outcome was graded in three categories: independence, dependence, or death. Poor outcome was defined as death or dependence. RESULTS: Of 29 patients with familial SAH, 52% had a poor outcome, whereas only 37% of 125 patients with sporadic SAH had a poor outcome. The crude relative risk for poor outcome in familial SAH was 1.4 (95% confidence interval [CI], 0.9 to 2.1; P = .14); the odds ratio adjusted for age and sex was 2.5 (95% CI, 1.0 to 6.0; P = .04). This risk is probably an underestimation due to our strict patient selection criteria. CONCLUSIONS: Patients with familial SAH have a greater risk of poor outcome than patients with sporadic SAH. This adds to the factors in favor of screening unaffected first-degree relatives of patients with familial SAH.

Adult↗
PubMed1995

The Cochrane Collaboration Stroke Review Group. Meeting the need for systematic reviews in stroke care.

BACKGROUND: There is a pressing need to identify which interventions are definitely effective in the prevention of stroke and in the treatment and rehabilitation of stroke patients, which interventions are definitely ineffective, and which interventions require further research. This information is most reliably obtained from reviewing all the available evidence from randomized controlled trials in a systematic way. SUMMARY OF COMMENT: There have been many (at least 8000) randomized controlled trials relevant to stroke. It would be difficult for any one individual to keep track of all these trials, and therefore most clinicians, therapists, and researchers are dependent, to some degree, on reviews of this literature. However, most current reviews are unsystematic and tend to be either incomplete or biased, so that their recommendations can be seriously flawed. Until now there has been no attempt to systematically identify all randomized controlled trials relevant to stroke (including subarachnoid hemorrhage), to review the data they contain, and to keep these reviews up-to-date in the light of new evidence. The Stroke Review Group has now been established within the Cochrane Collaboration to try to perform these tasks. There are presently 40 collaborators from 13 countries working on approximately 25 reviews. CONCLUSIONS: Identifying and reviewing all randomized controlled trials relevant to stroke should bring important benefits to patients and all those involved in purchasing or providing care for patients with stroke. The Cochrane Collaboration Stroke Review Group has started this process and would welcome help from anyone interested in collaborating in this enormous task.

Bias↗
PubMed1994

Prospective study of sentinel headache in aneurysmal subarachnoid haemorrhage.

Retrospective surveys of patients with subarachnoid haemorrhage suggest that minor episodes with sudden headache (warning leaks) may precede rupture of an aneurysm, and that early recognition and surgery might lead to improved outcome. We studied 148 patients with sudden and severe headache (possible sentinel headache) seen by 252 general practitioners in a 5-year period in the Netherlands. Subarachnoid haemorrhage was the cause in 37 patients (25%) (proven aneurysm in 21, negative angiogram in 6, no angiogram done in 6, sudden headache followed by death in 4). 103 patients had headache as the only symptom, 12 of whom proved to have subarachnoid haemorrhage (6 with a ruptured aneurysm). Previous bouts of sudden headache had occurred in only 2. Other serious neurological conditions were diagnosed in 18. In the remaining 93, no underlying cause of headache was found; follow-up over 1 year showed no subsequent subarachnoid haemorrhage or sudden death. In this cohort, acute, severe headache in general practice indicated a serious neurological disorder in 37% (95% CI 29-45%), and subarachnoid haemorrhage in 25% (18-32%). 12% (5-18%) of those with headache as the only symptom. The notion of warning leaks as a less serious variant of subarachnoid haemorrhage is not supported by this study. Early recognition of subarachnoid haemorrhage is important but will probably have only limited impact on the outcome in the general population.

Acute Disease↗
PubMed1994

Predictive value of clinical history and electrocardiogram in patients with transient ischemic attack or minor ischemic stroke for subsequent cardiac and cerebral ischemic events. The Dutch TIA Trial Study Group.

OBJECTIVE: Patients with cerebral ischemia have a high mortality rate. The most common cause of death is myocardial infarction. We attempted to identify risk factors for subsequent cardiac events in patients with cerebral ischemia by means of the history and electrocardiography performed with the patient at rest. DESIGN: The original inception cohort was entered in a multicenter randomized clinical trial (30 or 283 mg/d of aspirin) and followed up prospectively for a mean period of 2.6 years. SETTING: Patients were admitted to the hospital or seen in outpatient clinics. PATIENTS: Patients with one or more transient ischemic attacks (symptoms completely reversible within 24 hours) and patients with minor ischemic stroke (symptoms persisting for longer than 24 hours) were randomized, provided they were independent in most activities of daily living. Patients with a definite or probable source of embolism in the heart were excluded. A total of 3021 patients were included in the study. Follow-up was performed at 4-month intervals. MAIN OUTCOME MEASURES: Primary cardiac outcome events were defined as nonfatal myocardial infarction and cardiac death. Cardiac death included sudden death, fatal myocardial infarction, or death due to congestive heart failure; 189 patients suffered a cardiac death--82 of which were sudden deaths--or nonfatal myocardial infarction. RESULTS: By means of multivariate analysis, the following independent predictors for cardiac events were identified (hazards ratio/95% confidence limits): age older than 65 years (1.6/1.2 to 2.2), male sex (1.5/1.1 to 2.1), angina pectoris (1.5/1.0 to 2.3), diabetes (1.6/1.1 to 2.5), anterior infarction noted on electrocardiography (1.7/1.1 to 2.7), inverted T wave noted on the electrocardiogram (1.6/1.1 to 2.4), and left ventricular hypertrophy noted on electrocardiography (3.2/2.0 to 4.9). CONCLUSIONS: The history and the electrocardiogram obtained with the patient at rest are valuable tools for cardiac risk assessment in patients with recent cerebral ischemia.

Adult↗
PubMed1994

Silent infarction on a second CT scan in 91 patients without manifest stroke in the Dutch TIA trial.

The frequency of silent infarction is an important issue because it is a marker of vascular disease. We studied the occurrence of silent infarction in a sample of patients from the Dutch TIA trial, in which patients were randomized between 30 and 283 mg of aspirin. A total of 91 patients with TIA or non-disabling ischemic stroke and who did not suffer a stroke during a period of one to four years (mean 32 months) underwent CT scanning both on entry and at the end of the study. A cardiac source of embolism was an exclusion criterion for the trial. We found only one patient with a possibly silent infarction; in four patients a previously detected symptomatic infarct on CT was no longer visible. The rarity of silent infarction in this study may have several explanations; (1) the relatively short period of follow-up, (2) the selection of patients (no cardiac source of embolism), (3) the clinical monitoring at four monthly intervals aimed at detection of focal ischemia, (4) the use of aspirin. Given these circumstances, silent infarction is an infrequent problem.

Adult↗
PubMed1994

Prediction of intracerebral haemorrhage after carotid endarterectomy by clinical criteria and intraoperative transcranial Doppler monitoring.

Intracerebral haemorrhage is a serious complication after carotid endarterectomy. We tried to identify predictors of this event. Two-hundred-and-thirty-three operations were selected from a total of 280 because of reliable intraoperative transcranial Doppler data with regards to the increase of peak blood flow velocities and pulsatility indices in the ipsilateral middle cerebral artery after release of the internal carotid artery cross-clamp. We also recorded the occurrence of unilateral throbbing headache or hypertension after the operation. Five patients developed an intracerebral haemorrhage after the operation. Seventeen patients developed headache or hypertension after surgery, four of whom developed an intracerebral haemorrhage (p < 0.001; Fisher's exact test). The positive predictive value of headache, hypertension, or both, for intracerebral haemorrhage was 24% (diagnostic gain 22%). The negative predictive value, sensitivity and specificity were 99, 80 and 94%, respectively. The increase of peak blood flow velocities and pulsatility indices in patients who developed intracerebral haemorrhage was significantly higher than in patients who did not (p < 10(-5); one-way ANOVA). With appropriate cut-off levels for the increase of peak blood flow velocities (> or = 175% increase) or pulsatility indices (> or = 100% increase) after release of the cross-clamps, the positive predictive value of intraoperative transcranial Doppler for intracerebral haemorrhage was 100% (diagnostic gain 98%). The negative predictive value, sensitivity and specificity were 99, 80 and 100%, respectively.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1994

Prediction of intracerebral haemorrhage after carotid endarterectomy by clinical criteria and intraoperative transcranial Doppler monitoring: results of 233 operations.

OBJECTIVE: Identification of predictors of intracerebral haemorrhage after carotid endarterectomy. DESIGN: Retrospective comparison of patients who developed intracerebral haemorrhage and patients who did not, with special attention to intraoperative transcranial Doppler monitoring of the ipsilateral middle cerebral artery and postoperative signs and symptoms of hypoperfusion. SUBJECTS AND MATERIALS: Two-hundred and thirty-three patients were studied with regard to the increase of peak blood flow velocities and pulsatility indices after endarterectomy and to the occurrence of unilateral throbbing headache or hypertension. RESULTS: Intracerebral haemorrhage occurred in five cases. Seventeen patients complained of headache or showed hypertension, four of whom developed an intracerebral haemorrhage (p < 0.001; Fisher's exact test). The positive predictive value of headache, hypertension, or both, was 24% (diagnostic gain 22%). The negative predictive value, sensitivity and specificity were 99, 80 and 94%, respectively. The increase of peak blood flow velocities and pulsatility indices in patients who developed intracerebral haemorrhage was significantly higher than in patients who did not (p < 10(-5); one-way ANOVA). When cut-off levels for the increase of peak blood flow velocities and pulsatility indices were set to 175 and 100%, respectively, the positive predictive value of intraoperative transcranial Doppler was 100% (diagnostic gain 98%). The negative predictive value, the sensitivity and specificity were 99, 80 and 100%, respectively. CONCLUSION: An increase of peak blood flow velocity > or = 100% or pulsatility index > or = 100% after declamping predicts intracerebral haemorrhage more accurately than the occurrence of headache or hypertension. Transcranial Doppler monitoring can be used to identify patients at risk for intracerebral haemorrhage, in whom control of blood pressure and modest degrees of anticoagulation may be appropriate.

Cerebral Hemorrhage↗
PubMed1994

Measuring ataxia: quantification based on the standard neurological examination.

To quantify ataxia in a simple way four tests were developed and analysed, based on the neurological examination: a tapping test for the arms (test 1), another one for the legs (test 2), a quantified finger-to-nose test (test 3), and a modified Romberg test (test 4). All tests were performed by 115 volunteers, 13 patients with cerebellar ataxia and 25 patients with sensory ataxia due to neuropathy. The test-retest repeatability was excellent. Tests 1, 2 and 4 were age-dependent, with lower scores above age 65. On test 1, 2 and 4 both groups of patients performed worse than controls; the correlation with the ataxia scale of Nobile-Orazio and the modified disability Rankin scale was good (P < 0.05). Although test 3 could differentiate between sensory and cerebellar ataxia, it was not useful for quantifying the degree of ataxia. To determine the practical value of the four tests, 11 patients performed the tests for a second time after a follow up period of 16 months. The results indicate that tests 1, 2 and 4 are sensitive for the detection of ataxia and of changes in its severity.

Adult↗
PubMed1994

Visually induced central pain and arm withdrawal after right parietal lobe infarction.

A 46 year old man with ischaemic infarction of the right parietal cortex had left hemianaesthesia when his eyes were closed. With eyes open, visual stimuli induced withdrawal of the arm and a burning pain in the numb side of the body. Visually induced central pain is a new clinical finding and may be related to damage of cells with anticipatory inhibitory function in the parietal association cortex.

Arm↗
PubMed1994

Electroencephalography improves the prediction of functional outcome in the acute stage of cerebral ischemia.

BACKGROUND AND PURPOSE: We studied the value of clinical and electroencephalographic assessment in patients with acute first-ever supratentorial ischemia in predicting functional outcome after 1 year. METHODS: In 55 consecutive patients admitted after a median interval of less than 24 hours, the degree of handicap was dichotomized as moderate (Rankin grade 1, 2, or 3) or severe (Rankin grade 4 or 5). Clinical deficits were categorized according to signs of a lacunar or a cortical syndrome. Without knowledge of clinical data, electroencephalograms (EEGs) were classified according to findings predicting good or poor prognosis. The outcome after 1 year was assessed as good (Rankin grade 3 or less) or poor (Rankin grade 4 or 5 or death from stroke) and was correlated to clinical data and to EEG findings in the acute stage. RESULTS: Thirty patients with a moderate handicap on admission all had a good outcome (predictive value [PV] of the initial handicap, 1.00; 95% confidence interval [CI], 0.88 to 1.00). Of the 25 patients with severe handicap on admission a poor outcome occurred in 13 (PV, 0.52; 95% CI, 0.31 to 0.72). If these patients with severe handicap at baseline were subdivided according to clinical features, a lacunar syndrome predicted good outcome in 4 of 5 patients (PV, 0.80; 95% CI, 0.28 to 1.00), but a cortical syndrome predicted poor outcome in only 12 of 20 patients (PV, 0.60; 95% CI, 0.36 to 0.81). Of the 20 patients with severe handicap and a cortical syndrome at baseline, an EEG with features predicting a good prognosis correctly predicted good outcome in 6 of 7 patients (PV, 0.86; 95% CI, 0.42 to 1.00). An EEG with features predicting poor prognosis correctly predicted poor outcome in 11 of 13 patients (PV, 0.85; 95% CI, 0.55 to 0.98). CONCLUSIONS: Electroencephalography improves the prediction of functional outcome in patients with a severe neurological deficit in the acute stage of cerebral ischemia. This may have implications for the design of future intervention trials in acute stroke.

Activities of Daily Living↗
PubMed1994

Evidence for episodic platelet activation in acute ischemic stroke.

BACKGROUND AND PURPOSE: Enhanced thromboxane biosynthesis has previously been reported in patients with acute ischemic stroke. In this study we examined the time course of thromboxane biosynthesis after the onset of symptoms in 13 patients with acute cerebral infarction. METHODS: We obtained five to eight consecutive 6-hour urine samples from each of these 13 patients within the first 48 hours after onset of symptoms to study the dynamics of platelet activation in this setting. The urinary excretion of the major enzymatic metabolite of thromboxane B2, 11-dehydro-thromboxane B2, was measured by a previously validated radioimmunoassay. The excretion rate was compared with that of 20 control patients with nonvascular neurological diseases. RESULTS: Eleven patients (85%) had at least one value exceeding 2 SD of the control mean (251 pmol/mmol creatinine). The proportion of samples with an elevated 11-dehydro-thromboxane B2 level was markedly similar in each of the eight 6-hour collection periods (mean, 52 +/- 8%; range, 40% to 67%). In 4 patients (31%) the excretion rate was elevated in all measurements obtained. In the 11 patients with enhanced thromboxane biosynthesis, no uniform pattern of changes over time in metabolite excretion emerged, with 3 patients having peak values at 0 to 12 hours, 3 at 12 to 24 hours, 3 at 24 to 36 hours, and 2 at 36 to 48 hours. The level and dynamics of 11-dehydro-thromboxane B2 excretion were related neither to the neurological symptoms nor to the type or site of the cerebral ischemia. CONCLUSIONS: We conclude that episodes of platelet activation occur repeatedly during the first 48 hours after the onset of symptoms of an acute ischemic stroke. Given its apparent dynamic nature, this ongoing process may be amenable to pharmacologic modulation.

Adult↗
PubMed1994

Impact of microembolism and hemodynamic changes in the brain during carotid endarterectomy.

BACKGROUND AND PURPOSE: Monitoring of carotid endarterectomy with electroencephalography and transcranial Doppler ultrasonography provides instantaneous information about hemodynamic changes and embolic signals. However, a relation between these findings and intraoperative infarcts has not yet been demonstrated. METHODS: In this study we compared preoperative and post-operative computed tomographic scans (58 patients) or magnetic resonance imaging (40 patients) of the brain, assessed by two independent observers, to detect intraoperative infarcts, and we related any such new lesions to the findings of intraoperative monitoring. RESULTS: In the computed tomography series one intraoperative infarct occurred, with corresponding clinical deficits. In the magnetic resonance group four patients developed new lesions that occurred intraoperatively, all of which were clinically silent. There was a significant relation between the number of embolic signals during the surgical dissection of the carotid artery and the occurrence of intraoperative infarcts (P < .005). Three of the four infarcts were of the lacunar type; the fourth patient had a border-zone infarct, associated not only with many embolic signals but also with low flow during cross-clamping. There were no demonstrable ultrasound side effects on brain tissue. CONCLUSIONS: Embolic signals detected by transcranial Doppler monitoring in the dissection phase of carotid endarterectomy show a significant relation to new ischemic lesions and therefore are potentially harmful. The phenomenon should alert the vascular surgeon.

Adult↗