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G Rancurel

Publications and source records attributed to G Rancurel.

At least 37 records · Page 2Linked to original sources
PubMed1998

Frontal dysfunction in neurologically normal chronic alcoholic subjects: metabolic and neuropsychological findings.

BACKGROUND: Neuropsychological and imaging studies suggest that frontal dysfunction may occur in apparently normal chronic alcoholic subjects. METHODS: To investigate this issue further, we performed neuropsychological and fluorodeoxy-glucose-PET studies in 17 chronic alcoholics without patent neurological and psychiatric complications. RESULTS: Metabolic abnormalities were found in the mediofrontal and in the left dorsolateral prefrontal cortex, but not in the orbitofrontal cortex. Neuropsychological testing revealed significantly reduced verbal fluency and impaired performance on the Stroop test. The mediofrontal hypometabolism correlated with the reduction in verbal fluency and the time necessary to perform the interference condition of the Stroop test. The left dorsolateral prefrontal hypometabolism correlated with the number of errors on the Stroop test. CONCLUSION: These data indicate that circumscribed frontal dysfunctions may occur in chronic alcoholic subjects before clinically obvious neurological complications, and may account for some of the alcohol-related neuropsychological and behavioural impairments.

Adult↗
PubMed1998

Diffusion-weighted magnetic resonance imaging in a case of cerebral venous thrombosis.

BACKGROUND: Diffusion-weighted imaging (DWI) is the most sensitive MR sequence in acute arterial ischemic stroke but has not yet been evaluated in venous cerebral ischemia. We describe a patient with DWI performed at the acute phase of a venous ischemic stroke. CASE DESCRIPTION: A rapid cerebral MRI including DWI and fast fluid-attenuated inversion recovery (FLAIR) sequences was performed at the acute phase of a venous stroke confirmed by conventional angiography. DWI showed a slight decrease in apparent diffusion coefficient values 3 hours after onset (0.53+/-0.07x10(-3) mm2/s) and was normal 48 hours later (0.064+/-0.15x10(-3) mm2/s). Fast FLAIR sequences showed large left frontoparietal hyperintensities. The lack of a clear decrease in apparent diffusion coefficient values associated with marked FLAIR abnormalities may suggest prominent or early associated vasogenic edema. Physiopathological differences between arterial and venous ischemia may explain the different type of DWI FLAIR abnormalities during the acute phase as well as the better recovery of neurological deficit in venous stroke than in arterial ischemic stroke. CONCLUSIONS: In the context of an acute stroke, the contrast between marked FLAIR and subtle DWI abnormalities on MRI may reflect the venous mechanism of cerebral ischemia.

Brain↗
PubMed1998

Clinicometabolic dissociation of cognitive functions and social behavior in frontal lobe lesions.

OBJECTIVE/BACKGROUND: Case studies suggest a dissociation between cognitive functions that have been impaired after damage to the dorsolateral prefrontal cortex and social skills disturbed when the ventromedial prefrontal areas are affected. Because this dissociation had not been confirmed in a clinical setting, clinicometabolic correlations were sought in 13 patients with various lesions of the prefrontal cortex. DESIGN/METHODS: The clinical assessment included extensive testing of executive functions and evaluation of behavioral abnormalities based on an informant questionnaire. Regional cerebral glucose metabolism (rCMRGlu) was measured with [l8F] fluorodeoxyglucose ([18F] FDG) and 31-slide high-resolution PET. RESULTS: Executive-function test performance was significantly correlated with rCMRGlu in the dorsolateral prefrontal cortex (Brodmann's areas 8, 9, 45, 46, and 47) and anterior cingulate cortex (Brodmann's areas 24 and 32). Behavioral scores were significantly correlated with rCMRGlu in the frontopolar (Brodmann's area 10) and orbitofrontal cortex (Brodmann's areas 11, 12, 13, and 14). CONCLUSION: These results show that impaired executive functions and serial skill deficits are associated with distinct metabolic patterns in patients with frontal lobe pathology. In agreement with activation studies in normal subjects, our data suggest the existence of a modular organization of the frontal cortex in humans, as previously reported in nonhuman primates.

Adult↗
PubMed1997

Evolving isolated hand palsy: a parietal lobe syndrome associated with carotid artery disease.

Six patients with cerebral ischaemia who presented evolving isolated hand palsy were studied, five prospectively and one retrospectively. The motor deficit involved only the hand and the wrist in some cases. In almost all cases the motor deficit was pseudo-ulnar. None of them had a Babinski sign, all had mild sensory symptoms or signs in the affected hand. CT and MRI disclosed recent infarctions contralateral to the affected hand, in the white matter of the angular gyrus, in a vascular borderzone. Five had a tight stenosis of the internal carotid artery. The pyramidal tract was anatomically spared in three cases, even considering its parietal origin. Consistent with previous data, our study suggests that the parietal lobe is involved in the control of the motor function of the hand. We propose the existence of a new entity, characterized by an evolving non-pyramidal motor deficit in the hand following infarction of the angular gyrus of the inferior parietal lobe.

Aged↗
PubMed1997

[Visual hallucinosis and hyperhedonism in pontine and thalamic infarction].

The syndrome of peduncular hallucinosis in characterized by transient visual hallucinations which often consist in animated and mobile characters or animals, and which are often associated with disordered sleep. Although vivid and life) like, these hallucinations are generally not mistaken for reality. In view of the associated neurological symptoms, this syndrome was first believed to occur only with lesions of the mesencephalon. Lesions restricted to the mesencephalon have been identified with MRI in a few cases and were demonstrated by pathological verification in one patient with this syndrome. We describe a patient who experienced very similar hallucinations following a unilateral infarct restricted to the cerebellum, rostral protuberance and posterior thalamus. No lesion was seen in the mesencephalon with MRI. This case confirms that the lesions responsible for peduncular hallucinosis are not restricted to the mesencephalon, which suggests that several interconnected neural structures are probably involved in the genesis of this type of visual hallucinations. During the days following the stroke, our patient also experienced transient sensations of pleasure which he considered as abnormal. In view of the site of the lesions in this case, the visual hallucinations may be explained by a disinhibition of ponto-geniculo-occipital waves. A transient activation of reward-system pathways traveling in the brainstem ventral tegmentum may have contributed to the occurrence of the abnormal sensations of pleasure.

Cerebellum↗
PubMed1996

The neuropathologic diagnostic criteria of frontal lobe dementia revisited. A study of ten consecutive cases.

Ten successive cases from the Neuropathology Laboratory of La Salpêtrière Hospital in Paris, were selected on the presence of: dementia and prominent symptoms and signs of the frontal type; a degenerative disease without markers other than Pick cells, Pick bodies or ubiquitin-labelled non argyrophilic inclusions. We propose the following steps to diagnose the degenerative dementia associated with symptoms and signs of the frontal type: 1. If there is severe frontotemporal atrophy, severe neuronal loss and astrogliosis, many ballooned neurons and characteristic inclusions that are both tau and ubiquitin positive, the diagnosis is Pick disease. 2. If signs of motor involvement (sometimes unnoticed by the clinician) are present with mild cortical atrophy and mild spongiosis of layers II-III, the diagnosis of frontal lobe degeneration associated with motor neuron disease is warranted. Ubiquitin positive inclusions are useful, but non specific, markers. 3. When there are neither Pick inclusions nor motor neuron disease, the diagnosis may be frontal lobe atrophy lacking distinctive histology.

Adult↗
PubMed1996

Schizophreniform catatonia on 6 cases secondary to hydrocephalus with subthalamic mesencephalic tumor associated with hypodopaminergia.

This paper presents 6 patients with catatonia and subthalamic mesencephalic tumors with hydrocephalus involving the third and the lateral ventricles. This anatomic and psychiatric anomaly is investigated on the basis of personal observations and a review of the literature. These cases allow an interesting parallel to be traced between neurological clinical signs and psychiatric signs. Various anatomic and physiological models are discussed which emphasize specialized neuronal circuits (somewhat similar to those involved in Parkinson's disease) and certain specific neurotransmitters such as dopamine, together with the reactivity of these circuits to intracranial pressure variations. Once more, clinical and laboratory data on schizophrenia concur to suggest that organic etiology is the causal factor in a known psychiatric pathology.

Adult↗
PubMed1996

Impairment of central motor conduction to the diaphragm in stroke.

Respiratory complications are common in patients with stroke, but the involvement of the diaphragm in this setting is not completely understood. The purpose of this study was to assess corticodiaphragmatic pathways in patients with vascular hemiplegia. Fifteen patients were studied, nine with a capsular type of hemiplegia. Seven age-matched subjects served as the control group, and eight healthy young volunteers were studied to validate the methods by comparison with the literature. Diaphragm electromyogram was recorded bilaterally, using surface electrodes. Abductor pollicis brevis electromyogram was also recorded. After having checked the integrity of peripheral conduction, corticofugal pathways were studied using cortical magnetic stimulation, a reproducible and patient-independent stimulus. Left and right conduction times to the diaphragm were symmetrical in the control subjects, the young volunteers, and the six patients with hemiplegia but without capsular lesion (16.5 to 20.1 ms). Conversely, they were markedly asymmetrical in patients with capsular hemiplegia, diaphragm response on the plegic side being abolished or markedly delayed. Although the clinical impact of these findings remains to be determined, this study confirms that "central diaphragm paralysis" can be present in stroke. It also indicates that there is no bilateral motor representation of each hemidiaphragm.

Adult↗
PubMed1996

Recovery from nonfluent aphasia after melodic intonation therapy: a PET study.

We examined mechanisms of recovery from aphasia in seven nonfluent aphasic patients, who were successfully treated with melodic intonation therapy (MIT) after a lengthy absence of spontaneous recovery. We measured changes in relative cerebral blood flow (CBF) with positron emission tomography (PET) during hearing and repetition of simple words, and during repetition of MIT-loaded words. Without MIT, language tasks abnormally activated right hemisphere regions, homotopic to those activated in the normal subject, and deactivated left hemisphere language zones. In contrast, repeating words with MIT reactivated Broca's area and the left prefrontal cortex, while deactivating the counterpart of Wernicke's area in the right hemisphere. The recovery process induced by MIT in these patients probably coincides with this reactivation of left prefrontal structures. In contrast, the right hemisphere regions abnormally activated during simple language tasks seem to be associated with the initial persistence of the aphasia. This study supports the idea that abnormal activation patterns in the lesioned brain are not necessarily related to the recovery process.

Adult↗
PubMed1996

[Contribution of position emission tomography in a case of Marchiafava Bignami disease: Morel's laminar sclerosis?].

We report the case of a 26-year old alcoholic woman who abruptly presented with confusion associated with a major hypertonia. She evolved into a chronically vegetative state. Magnetic resonance imaging (MRI) was consistent with the diagnosis of Marchiafava Bignami disease. The corpus callosum first presented an oedematous aspect, then a central atrophy with an axial band. The clinical presentation and the functional imaging strongly suggest an association between the Marchiafava Bignami disease and diffuse cortical lesions, such as the laminar sclerosis of Morel.

Acute Disease↗
PubMed1996

[Spontaneous dissection of the internal carotid artery in ophthalmological milieu. Apropos of 10 cases].

PURPOSE: Spontaneous dissection of the internal carotid artery is a rare vascular emergency, but represents the first cause of cerebral ischaemia of young patients. Neuro-ophthalmologic symptoms often reveals the pathology. METHODS: Ten cases of spontaneous dissection of the internal artery are reported. The Claude Bernard Horner syndrome is the most frequent symptom typically associated with hemicranial headache. The headache involves the ipsilateral forequarter of the head and the neck. Other ophthalmologic symptoms may also reveal the carotid dissection. RESULTS: At first, the diagnosis is strongly suspected during Doppler ultrasonographic examination. During the acute phase, MRI and MRA replaces advantagiously arteriography, confirming this affection in a non invasive way, and permits investigation of associated vascular pathology like fibromuscular dysplasia (15% of the cases). The patients received anticoagulants in order to prevent thrombo-embolic complications (heparine during the acute phase relayed by AVK). The clinical course is usually favorable with the medical treatment. CONCLUSION: A painful Claude Bernard Horner syndrome strongly evokes a carotid dissection and the arterial check-up must be realised in emergency: at first, the exploratory methods associates Doppler ultrasonographic examination, MRI, and MRA.

Adult↗
PubMed1996

Post-stroke changes in cortical 5-HT2 serotonergic receptors.

UNLABELLED: Fluorine-18-setoperone PET imaging was used to investigate serotonergic 5-HT2-specific binding in unlesioned cerebral cortex in stroke patients. METHODS: Seventeen stroke patients (mean age 50 +/- 31 yr) with right (n = 9) or left (n = 8) chronic stroke (middle or anterior cerebral artery territory) underwent [18F]setoperone PET and MR imaging. The distribution volume of the 5-HT2-specific binding at equilibrium (DVSe) was determined in the unlesioned cortical regions. The results were compared with those obtained in 14 age-matched controls. In addition, we investigated the effect of the side of the stroke, lesion volume and its localization. RESULTS: After removing the age effect by covariance analysis, we found a significant DVSe decrease in the temporal (p < 0.05) and frontal (p < 0.05) unlesioned cortices ipsilateral to the stroke. The changes were similar in patients with left and right stroke and did not correlate with the volume of the stroke. However, the localization of the stroke affected the topography of DVSe abnormalities. When the lesion did not extend more medially than the internal capsule, DVSe was significantly reduced in the temporal lobe (-30%, p < 0.05) but not in the frontal lobe (-21%, p = ns). Conversely, when the lesion extended subcortically in the anteromedial region, close to the midline, DVSe was reduced in both temporal (-40%, p < 0.05) and frontal (- 49%, p < 0.05) lobes. CONCLUSION: This study confirms that stroke may alter 5-HT2 receptors in large unlesioned cortical areas and that the changes depend on the subcortical extent of the lesion.

Adult↗
PubMed1995

Aphasia and infarction of the posterior cerebral artery territory.

Spoken language disorders are rarely mentioned in superficial infarction of the posterior cerebral (PCA) territory. Two clinical types have been reported: transcortical sensory and amnesic aphasia. Between 1979 and 1990, we studied retrospectively 76 patients suffering from an occipitotemporal infarction located in the superficial territory of the posterior cerebral artery, all well documented by CT. Aphasia was one of the first and prominent signs in 18 cases. Middle cerebral artery concomitant infarction could have been the cause of language impairment in 10. In 8 patients aphasia was only explained by a PCA territory infarct. Three patients showed features of transcortical sensory aphasia. CT localization showed internal lobe and thalamic involvement of the dominant hemisphere. Five patients exhibited word finding impairment with various degrees of amnestic syndrome. The dominant internal temporal lobe was always affected. Dominant thalamus involvement was found in one case only. Some correlations between clinical features and anatomical support (vascular supply and anatomical structure) might be suggested in our 8 cases of aphasic disorders due to PCA infarcts. They are discussed and compared with data in the literature.

Adult↗
PubMed1995

Carotid eversion endarterectomy: short- and long-term results.

From January 1979 to December 1993, of 2723 carotid revascularizations performed on our service, 168 (6.2%) were isolated carotid eversion endarterectomies (CEEs) for atherosclerotic occlusive disease. Since 10 of these procedures were bilateral, there were 158 patients total (88 men and 70 women). Twenty-six (16.5%) had diabetes, 54 (34.2%) had coronary disease, and 107 (67.7%) had hypertension. The mean age was 68.9 +/- 8.9 years (range 38 and 85 years). Preoperative ischemic symptoms were hemispheric in 93 (55.4%) patients, retinal in 31 (18.4%), and vertebrobasilar in 37 (22%). They consisted of one or more strokes in 44 (26.2%) patients and one or more transient ischemic attacks in 99 (58.9%); 25 (14.9%) patients were asymptomatic. The operated lesion contained atherosclerotic stenotic plaque in all cases. The lesion was tightly stenotic (> 75%) and hemodynamically significant in 93 (55.4%) cases and irregular or ulcerated in all others. In 86 (51.2%) patients a coil or kink of the distal internal carotid artery was also present. The contralateral carotid artery was totally occluded in eight (4.7%) patients and tightly stenotic in seven (4.2%). All patients were operated on under deep general anesthesia; they were given systemic heparin and normal blood pressure was maintained. After freeing and cross-clamping of the carotid bifurcation, the end of the common carotid artery or the ostium of the internal carotid artery was sectioned. The section allowed a deep-plane endarterectomy through eversion and excellent control over the endarterectomized surface and its extremities. Since January 1989 completion arteriography has been routinely performed after CEE.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗