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Biomedical subjects

F Dubas

Publications and source records attributed to F Dubas.

At least 55 records · Page 3Linked to original sources
PubMed1994

Ultrasonic features of extracranial carotid dissections: 47 cases studied by angiography.

The purpose of this prospective study was to assess the value of continuous wave Doppler velocimetry, standard duplex scanning and color Doppler flow imaging in the diagnosis of carotid dissections. From 1975 to 1993, 42 patients (mean age, 44 +/- 14 years) were admitted to the University Hospital of Angers for a carotid dissection studied first by ultrasonography, then defined by angiography. Five cases were bilateral. Continuous wave Doppler examination revealed signs of severe obstruction of the carotid arteries in 96% of the cases (occlusion, extensive submandibular tight stenoses, significant slowdowns in the carotid and ophthalmic vessels, retrograde ophthalmic blood flow). Standard duplex scanning suggested dissection in 72% of the cases (tapering stenoses or occlusion, segmental ectasis, tubular vessel, peripheral residual channel, or rare irregular "membrane"). Color Doppler flow imaging suggested a dissection in 82% of the cases. This method has the advantage of underlining the peripheral channel, the double lumen, and the dissecting hematoma, which often is hypoechoic. The ultrasonic methods (continuous wave Doppler combined with color Doppler flow imaging) failed only when they are performed late and when moderate or segmental intrapetrosal dissections were present. These ultrasonic investigations would thus appear to be useful for early diagnosis of carotid dissections.

Adult↗
PubMed1994

[Doppler transcranial ultrasonography in carotid and vertebral dissections: 36 cases involving angiography].

The aim of this prospective study was to investigate the additional information provided by transcranial pulsed Doppler for the determination of the upper part of dissections of the carotid and vertebral arteries and following-up. Earlier results concerning the role of ultrasound investigations for this indication have been presented elsewhere. Twenty-nine patients were examined (17 females, 12 males; mean age 43 years). All had arterial dissections confirmed by arteriography. There were 24 carotid dissections and 12 vertebral dissections. Investigations were performed during the acute phase and 2 months later. Most of the severe endocranial stenoses were identified by transcranial Doppler: 5 out of 6 severe stenoses of the carotid siphon and 6 out of 7 vertebral stenoses. The haemodynamic effect as measured by sylvian flow was significantly greater (p < 0.01) after a permanent ischaemic event than after temporary events and improved significantly with time (p < 0.008). There was no significant variation in the pulsatility transmission index (PTI), but this index requires a reference artery and is not particularly adapted in cases with bilateral dissection. Collateral perfusion, observed during the acute phase in all cases of occlusion and in 6 of the 8 carotid stenosis, was insufficient in half of the cases. Transcranial pulsed Doppler can be used to guide arteriography and helps determine the length of the dissection. It provides an easy way to assess the haemodynamic consequences of the dissection and is quite useful during follow-up.

Adult↗
PubMed1993

Autosomal dominant leukoencephalopathy and subcortical ischemic stroke. A clinicopathological study.

BACKGROUND AND PURPOSE: We recently described an autosomal dominant syndrome characterized mainly by recurrent strokes and neuroimaging evidence of leukoencephalopathy. We now report the pathological findings in one of the affected subjects. CASE DESCRIPTION: A 40-year-old woman experienced her first grand mal seizure in 1971. From 1983 on she suffered recurrent strokes, seizures, and psychiatric disturbances with depressions, manic episodes, and dementia. In 1988, after her fourth stroke, she became tetraplegic with a severe pseudobulbar palsy, and she died in 1990. Pathological examination disclosed a recent capsulolenticular hematoma, multiple small deep infarcts, a diffuse myelin loss and pallor of the hemispheric white matter, and a widespread vasculopathy of the small arteries penetrating the white matter. The arterial wall was markedly thickened with an extensive nonamyloid eosinophilic deposit in the media and reduplication of the internal elastic lamella. CONCLUSIONS: The underlying lesion of this hereditary disorder is located in the small arteries and is of unknown etiology. It differs from arteriosclerotic and amyloid angiopathies but is similar to that described in some cases of hereditary multi-infarct dementia.

Adult↗
PubMed1992

Uneven distribution of mitochondrial DNA mutation in MERRF dizygotic twins.

A new family of myoclonic epilepsy with ragged-red fibers (MERRF) was studied at clinical, histological, biochemical and molecular genetic levels. There was a remarkable variation in the age of onset, the clinical presentation and the severity of symptoms. Multiple defects affecting respiratory chain complexes I, III and IV were detected in 2 patients. The point mutation at 8344 of the mitochondrial genome was found in all the maternal lineage with a relatively narrow range of variation in the percentage of mutant mitochondrial genomes. The one exception was represented by a set of dizygotic twins, one clinically affected and showing high proportions of mutant mitochondrial DNAs (mtDNAs) in blood cells, while the other was asymptomatic and showed very small amounts of mutant mt-DNAs in blood and skin. This could suggest an early segregation of the mitochondrial genome during ovogenesis.

Adult↗
PubMed1992

Cavernomas of the spinal cord: report of two patients.

Two operated cases of spinal cord cavernomas are presented. Since spinal angiography is usually normal and myelography not specific, the contribution of magnetic resonance imaging to the diagnosis is emphasized. Surgical considerations of treatment are discussed.

Adult↗
PubMed1992

[Cerebrovascular complications of cancers].

About 15% of patients with cancer have cerebrovascular lesions, resulting from 4 kinds of disorders sometimes intermingled in advanced disseminated cancer: coagulation disorders, direct effects of the tumor, infections and therapeutic measures. Infarction, hardly less frequent than hemorrhage, mostly complicates lymphoma and carcinoma. Hypercoagulation states, such as chronic disseminated intravascular coagulation, nonbacterial thrombotic endocarditis, and nonmetastatic cerebral venous thrombosis account for about 50% of cases. Tumor emboli, as seen in intravascular malignant lymphomatosis, arteritis related to aspergillus, granulomatous angiitis with or without herpes zoster and radiation-induced atherosclerosis are rarer. Cerebral hemorrhages, excluding bleeding from the metastases of choriocarcinoma and melanoma are mainly associated with leukemia by acute disseminated intravascular coagulation as in promyelocytic leukemia, by leukostasis or by pancytopenia. Both infarction and hemorrhage rarely reveal the neoplasia. Lesions are often small and disseminated, and therefore produce a picture of diffuse acute or subacute encephalopathy rather than acute focal deficits. Finally, there may be no relationship between the cerebrovascular event and the neoplasia, and atherosclerosis or traumatic subdural hematoma may well be the causal factor.

Arteritis↗
PubMed1992

[Obsessive-compulsive behavior (arithmomania). Atrophy of the caudate nuclei].

We report the case of a 56-year-old woman who died after a 2.5 years progressive course of behavioral disorders associating severe obsessive-compulsive counting with disinhibition. Neuropathological examination showed severe gliosis of the caudate nuclei whereas the lentiform nuclei and frontal cortex were not involved. In contrast with previous reports, this case lacked psychic akinesia which is usually combined with obsessive-compulsive behavior. It is a further illustration of how subcortical lesions can produce a frontal like syndrome. It suggests a fundamental role of the caudate nuclei in the control of behavior.

Atrophy↗
PubMed1991

[Paraneoplastic neurologic syndromes].

Paraneoplastic neurological syndromes are of two types: some are more often seen without than with cancers and may therefore be called "occasionally para neoplastic" (e.g. chronic sensorimotor polyneuropathy and polymyositis), while others are fairly regularly associated with cancers, and particularly with small cell lung carcinoma. In this category falls subacute encephalomyelitis, an entity of broad anatomico-clinical spectrum including limbic encephalitis and subacute sensory neuronopathy; the patient's serum and cerebrospinal fluid may contain neuronal antinuclear antibodies. One type of subacute cerebellar degeneration is characterized by the presence of antibodies specifically directed against Purkinje cell cytoplasmic antigens, and it is associated with ovarian and mammary cancers. The other type shows no antibodies or different antibodies and sometimes neuronal antinuclear antibodies; the latter case may represent the cerebellar form of subacute encephalopathy. Because it may be either a true autoimmune disease or a true paraneoplastic syndrome, Lambert-Eaton myasthenic syndrome, caused by autoantibodies that block the voltage-dependent calcium channels, stands out as the most convincing argument in support of the autoimmune paraneoplastic syndrome theory. The theory, which refers to cross-antigenicity, cannot be extended to the other syndromes without reservation: there is no evidence that autoantibodies are neurotoxic, and specific autoantibodies in high levels are sometimes detected in patients with cancer but without any neurological symptom. Nevertheless, the finding of circulating antineuronal antibodies in patients with a suggestive clinical syndrome should prompt investigations for cancer perhaps at an early stage.

Autoimmune Diseases↗
PubMed1990

[Chronic encephalitis with mesencephalic predominance. A clinico-pathologic case].

A 70 year-old woman presented with a progressive supranuclear ophthalmoplegia, with "apraxia" of eyelid opening, axial akinesia and dementia. CT scan showed a mild cortico-subcortical atrophy and there was a high level of immunoglobulins, with an oligoclonal pattern, without cell reaction in the CSF. The patient died two years after the onset. Post-mortem examination, limited to CNS, showed subacute encephalitis confined to the tectal, pretectal, subthalamic areas and to Ammon's horns. These changes and their location were strongly suggestive of polioencephalomyelitis with or without cancer, in which such a prevalent midbrain involvement has been exceptionally described.

Aged↗