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D Laplane

Publications and source records attributed to D Laplane.

At least 19 recordsLinked to original sources
PubMed1992

Brain energy metabolism in bilateral paramedian thalamic infarcts. A positron emission tomography study.

Positron emission tomography (PET) studies of the cerebral metabolic rate of oxygen (CMRO2) were performed in seven consecutive patients with bilateral paramedian thalamic infarcts (BPTI), selected on neuroradiological and clinical criteria. The latter consisted of sudden onset of coma or confusion followed by a persistent amnesia of varying severity, with or without language impairment and frontal lobe signs. There was a highly significant decrease of CMRO2 for the whole cortex as well as for all the regions analysed: medial-frontal, latero-frontal, temporal, sensorimotor and posterior associative cortex. The mean regional metabolic ratios (region/whole cortex CMRO2) were not significantly different from controls, indicating an essentially uniform effect in the cortex, except the sensorimotor ratio which was significantly increased. Diffuse cortical hypometabolism most likely reflects thalamo-cortical deafferentation secondary to damage to the 'non-specific' thalamic nuclei, while sparing of the latero-ventral thalamus presumably explains the relative preservation of the sensorimotor cortex metabolism. Although no clear-cut individual relationship was found between magnitude of cortical hypometabolism and the severity and pattern of neuropsychological impairment, the data suggest that the former underlies and/or reflects the latter. Further studies with higher resolution PET devices might shed more light on the relationships between distinct cognitive patterns and specific topography of cortical hypometabolism in BPTI patients.

Adult↗
PubMed1992

Lesions of basal ganglia due to disulfiram neurotoxicity.

Three cases of disulfiram induced Parkinsonism and frontal lobe-like syndrome associated with bilateral lesions of the lentiform nuclei on CT scan are reported. Symptoms developed either after an acute high dose of disulfiram (one case) or after several days to weeks of disulfiram treatment (two cases) and persisted over several years in two patients. These observations suggest that basal ganglia are one of the major targets of disulfiram neurotoxicity. The mechanisms of the lesions of basal ganglia may involve carbon disulfide toxicity.

Adult↗
PubMed1992

[Dementia disclosing primary Gougerot-Sjögren syndrome].

Two cases of primary Sjögren's syndrome revealed by dementia are reported. The patients had progressive or subacute memory dysfunction and psychiatric disorders with depression and delirium. The diagnosis of Sjögren's syndrome was established by biopsy of the minor salivary glands. Both patients were treated with corticosteroids. The neuropsychiatric symptoms improved dramatically in one case and remained unchanged in the other case. Dementia in Sjögren's syndrome seems to be without aphasia, apraxia or agnosia, and associated with psychiatric features, particularly depressive symptoms, thus including some characteristics of subcortical dementia. Diagnosis may be difficult because, as shown in our cases, symptoms of ocular and buccal dryness can be absent. Salivary gland biopsy can be useful in the evaluation of patients with dementia of undetermined etiology.

Biopsy↗
PubMed1991

[Language and thought].

Mixing, however briefly, with aphasic subjects is sufficient to show that though survives language alterations. Everyone's experience of forgetting proper names and common nouns clearly shows that concepts outlive words. Analyzing puns and allusions also reveals that the meaning of a word depends on a context of signification which may or may not be supplied verbally. Studying thought without language in both animals and infants provides evidence not only that language facilitates the exercise of cognitive functions but also that the initial progress facilitates the exercise of cognitive functions but also that the initial progress made by children is not related to language but to brain maturation. Dealing with the question of right hemisphere performance in patients with a brain split by callosotomy demonstrates, better than anything else, that each position taken on this question is underlain by philosophical presuppositions. In contradistinction with philosophies derived from that of Wittgenstein and from logical positivism and functionalist cognitivist theories, the author argues that all we know is through and within our thought, that all we say is thought and that, consequently, no scientific, philosophical, poetical or other discourse is able to apprehend or restrain thought. Thought extends far beyond language, including scientific language.

Animals↗
PubMed1991

PET studies of cortical diaschisis in patients with motor hemi-neglect.

Six patients presenting with multimodal, predominantly motor hemi-neglect, were investigated by 15O2 or 18F-DG and PET to study the local cerebral metabolism in intact regions. All had suffered from an acute right-sided (n = 5) or left-sided (n = 1) focal hemispheric lesion (cortico-subcortical and purely subcortical in three patients each). Frontal and parietal cortices on the side of the lesion were significantly hypometabolic relative to the other side in each case, presumably as a result of diaschisis, whereas thalamic hypometabolism was significant in only 4 patients. Compared to absolute metabolic rates for controls, the uninjured hemisphere showed a trend towards hypometabolism. Hence, true hyperactivity of the contralateral hemisphere with respect to the ipsilateral cerebral cortex was not associated with motor hemineglect in this series. On the contrary, hemineglect was associated with a widespread hypometabolism of the entire ipsilateral cerebral cortex in the context of a moderately reduced metabolism of the ipsilateral thalamus and contralateral cerebral cortex. These findings are consistent with the implication of a cortico-subcortical network serving attention.

Aged↗
PubMed1990

[Dissection of the extracranial internal carotid artery. 62 cases].

The results of a study of 62 patients with 69 dissections of the extracranial internal carotid artery are presented. Mean age at the time of diagnosis was 43 years, with a preponderance of men over women. The patients were followed up for a mean period of 41 months. In 6 cases regarded as being "traumatic" in origin, the outcome was similar to that of "spontaneous" dissection. The most significant associated factors seemed to be migraine (34 per cent), on-going treatment with oestrogens and progestogens (48 per cent of women) and fibromuscular dysplasia (21 per cent). The clinical features consisted of local signs (isolated in 8 cases), signs of ischaemia (isolated in 9 cases) or both together. There were 35 established cerebral vascular accidents and 2 cases of ischaemic optic neuritis with blindness, responsible for invalidating sequelae in 31 per cent of the patients. The most frequent local signs were suggestive hemicrania, cervical pain, Horner syndrome and tinnitus. The initial angiography showed occlusion in one quarter of the cases and stenosis in 70 per cent. Stenosis was usually located in the second infrapetrosal half of the artery and had the most favourable angiographic prognosis.

Adolescent↗
PubMed1990

[Alcohol and epilepsy].

Two kinds of epileptic events are frequently related to alcohol consumption: 1) seizures triggered by alcohol withdrawal. Often multiple, they occur within between 10 and 48 hours after discontinuing or reducing alcohol intakes and can be followed by a delirium tremens. 2) recurring unprovoked seizures. They are usually rare, 1 or 2 yearly. The risk is increased for heavy drinkers but returns to normal for ex-drinkers. Seizures related to alcoholism are usually generalized tonico clonic seizures with normal EEG and CT-scan. When partial seizures are identified they are attributed to preceding brain damage, head trauma or stroke.

Alcohol Drinking↗
PubMed1990

Kearns-sayre syndrome. Two clinico-pathological cases.

Two clinico-pathological cases of Kearns-Sayre syndrome are reported. In both cases the typical triad (progressive external ophthalmoplegia, heart block, retinitis pigmentosa) was present and spongiosis was the main pathological finding. In one case there was also a marked capillary proliferation, significance of which is discussed. A deletion of the mitochondrial DNA was found in the muscle, spinal cord and brain of this last case.

Adolescent↗
PubMed1990

[Loss of psychic self-activation].

Loss of motivation is a well-known disorder in patients with frontal lesions or, as more recently described, with bipallidal lesions. Some of these patients also report a kind of fading of their mental life when they are without exogenous stimulation. Yet their performances return to normal (or almost normal) levels under the influence of a social stimulation. It is this dissociation which we propose to call "loss of psychic self-activation" (LPSA). Comparisons with disorders produced by similar lesions suggest that this is not an "all or none" phenomenon. The purpose of this paper is to discuss the originality, usefulness and validity of the loss of psychic self-activation concept and to evaluate its heuristic value, notably in its application to Janet's psychasthenia and to obsessional neurosis. An interpretation of this disorder based on the available anatomical data is also tentatively proposed.

Activities of Daily Living↗
PubMed1990

Neurosarcoidosis: signs, course and treatment in 35 confirmed cases.

Thirty-five cases of biopsy-proven sarcoidosis with neurologic manifestations are reported. Neurosarcoidosis was the presenting symptom in 31% of cases and the only clinical manifestation in 17%. Mean follow-up time was 48 months. Central nervous system involvement was observed in 37% and meningitis in 40% of patients. Other manifestations were cranial nerve palsies (37%), peripheral neuropathy (40%), and myopathy (26%). Multiple neurologic manifestations were present in 51% of cases. All but 4 were treated with corticosteroids. Another immunosuppressive agent or cerebral irradiation was added in 6 and 2 patients, respectively. Complete recovery was observed in 46%, improvement in 46%, 4% remained stable, and 4% worsened. There were no deaths. We advocate treating neurosarcoidosis with corticosteroids as early as possible. If the patient's condition worsens, additional immunosuppressive agents or cerebral irradiation is warranted.

Adolescent↗
PubMed1990

[Is there a correlation between motor neglect and unilateral sensory neglect].

Similarities between motor neglect and unilateral sensorial neglect are so striking that their mechanisms are likely to be almost the same. As the attentional interpretation is no longer possible for motor neglect, and the intentional interpretation may be dismissed in man because of the loss of automatic movements, the psychological interpretation must be abandoned. A purely physiological hypothesis is put forward for motor neglect. When applied to unilateral neglect, it suggests that sensorial signals treated by the right hemisphere do not reach a significant functional level. In such case, the left hemisphere assumed to be dominant for awareness of body and space would receive from the right hemisphere a message interpreted as nul and would neglect information coming from the left.

Brain Diseases↗
PubMed1989

[Practical management of Alzheimer's disease].

In patients with confirmed Alzheimer's disease--a condition for which no active treatment is available--the practitioner's first duty is to abstain from prescribing useless of harmful drugs that would make the situation worse. There is a long list of such potential nuisances. The most badly tolerated drugs unquestionably are anticholinergics, but one must also beware of tricyclic antidepressants, neuroleptics (sometimes unavoidable, however) and also, to a lesser extent, benzodiazepines, beta-blockers and so forth. Yet medical support is far from being ruled out. The benefits of placebos and drugs of undemonstrated value are not negligible, but above all it is mandatory to help the relative understand the truly pathological nature of almost unbearable behaviours. It is also very useful to advise the family on the life organization at home in order to perdure, on the legal safeguards, on whether or not the patient should be institutionalized, and similar topics. Inside institutions, keeping a sensible attitude between relentless therapy and euthanasia is the best way to ensure that the dignity of the demented patient will be preserved.

Alzheimer Disease↗
PubMed1989

Peripheral neuropathies during treatment with almitrine: report of 46 cases.

Almitrine bismesylate is thought to cause sensory peripheral neuropathy. Forty-six patients are reported who received almitrine bismesylate alone for chronic respiratory failure or in combination with raubasine for various cerebrovascular diseases. Polyneuropathy appeared between 9 and 25 months after the onset of treatment. Sensory signs and symptoms were confined to the distal parts of the lower limbs and involved large and small fibres. Histological and electrophysiological findings indicated axonal degeneration. Respiratory failure could have caused the polyneuropathy in some cases but many had no chest disease. Patients began to improve between 3 and 6 months after withdrawal of the drug. Recovery was usually complete after 12 months.

Aged↗
PubMed1989

Obsessive-compulsive and other behavioural changes with bilateral basal ganglia lesions. A neuropsychological, magnetic resonance imaging and positron tomography study.

Eight patients are reported who shared the combination of bilateral basal ganglia lesions and a frontal lobe-like syndrome. The main features were inertia and loss of drive, with preservation of intellectual function. Some patients showed stereotyped activities with compulsive and obsessive behaviour which were sometimes highly elaborate in pattern. Extrapyramidal clinical signs were absent or mild. Brain damage, related to anoxic or toxic encephalopathy, was demonstrated by CT scans and MRI. The lesions appeared to be confined to the lentiform nuclei, particularly affecting the pallidum, although there was generalized brain atrophy in 2 cases. Positron emission tomography (PET) in 7 patients revealed hypometabolism of the prefrontal cortex relative to other parts of the brain. The PET studies suggest dysfunction of the prefrontal cortex as a result of damage to the lentiform nuclei. These clinical, anatomical and functional observations emphasize the role of the circuits linking the prefrontal associative cortex and some specific areas of the neostriatum, including the pallidum. The existence of distinct nonoverlapping circuits in the motor field or in the associative field can explain the fact that basal ganglia lesions may give rise to a clinical picture that is either purely motor, purely behavioural (as in some of our patients), or both. Similarities existed between some symptoms found in our patients and certain features of major psychiatric illnesses such as severe depression, catatonic schizophrenia, and obsessive-compulsive disorder. This raises the hypothesis that some aspects of these psychiatric disorders could be related to structural and physiological disturbances in the systems linking the frontal associative cortex and the basal ganglia.

Adult↗
PubMed1989

[Cerebellar infarction in the area of the posterior cerebellar artery. Clinicopathology of 28 cases].

We report a neuropathological study of cerebellar infarctions involving the territory of the posterior inferior cerebellar artery (PICA) in 28 cases. Fifteen cases involved the PICA territory only. In 13 cases infarctions in the anterior inferior cerebellar artery (AICA) territory and/or in the superior cerebellar artery (SCA) territory were also present. A thorough post-mortem study of the arterial supply of the brain from the heart up to the cerebellar arteries, including the cervical spine segment of the vertebral arteries was performed in 27 cases. The territory of the cerebellar infarcts has been ascertained. In 15/28 cases (54 percent), infarction involved the PICA territory only (17 infarcts). All of these cases had a benign outcome and death was due to another cause. Six of these were recent infarctions. None had evidence of swelling and tonsillar herniation. Infarcts were generally of small size and involved the entire PICA territory in only 2 cases. Most of these cases were unexpected discovered at autopsy. Cerebellar infarction in the territory of the medial branch of the PICA (9/17 infarcts) drew grossly a set square with a dorsal base and a ventral top headed for the IVth ventricle. Five out of these cases were associated with infarction in the dorsal and lateral medullary territories. Retrospective clinical study showed that they had been unnoticed or overshadowed by other neurological disorders (4 cases), or presented as Wallenberg's syndromes (4 cases), or as a pure vestibular syndrome (due to an infarction involving only the cerebellum) mimicking an acute labyrinthine disorder (1 case). Infarctions in the territory of the lateral branch of the PICA (5/17 infarcts) always occurred without medullary involvement. All of them were unexpectedly discovered at autopsy, and were unnoticed during the life (3 infarcts) or were overshadowed by other neurological disorders (2 infarcts). That was also the case in 2 cases of infarction in the whole PICA territory (3/17 infarcts). Thus infarctions strictly localized to the entire PICA territory only were rare. Thirteen/28 cases (46 p. 100) of infarction in the whole PICA territory were associated with infarction in the AICA and/or the SCA territories. This resulted from an association with other infarctions and not from an abnormally large territory of the PICA. Cerebellar swelling with brain stem compression and tonsillar herniation occurred 8/13 cases (62 p. 100). There were other massive median and paramedian brain stem infarctions involving midbrain, pons or medulla in 55 p. 100 of 13 cases.(ABSTRACT TRUNCATED AT 400 WORDS)

Aged↗