Advanced multiparametric magnetic resonance imaging of multinodular and vacuolating neuronal tumor.

BACKGROUND AND PURPOSE: Multinodular and vacuolating neuronal tumor (MVNT) of the cerebrum is a rare brain lesion with suggestive imaging features. The aim of our study was to report the largest series of MVNTs so far and to evaluate the utility of advanced multiparametric magnetic resonance (MR) techniques. METHODS: This multicenter retrospective study was approved by our institutional research ethics board. From July 2014 to May 2019, two radiologists read in consensus the MR examinations of patients presenting with a lesion suggestive of an MVNT. They analyzed the lesions' MR characteristics on structural images and advanced multiparametric MR imaging. RESULTS: A total of 64 patients (29 women and 35 men, mean age 44.2 ± 15.1 years) from 25 centers were included. Lesions were all hyperintense on fluid-attenuated inversion recovery and T2-weighted imaging without post-contrast enhancement. The median relative apparent diffusion coefficient on diffusion-weighted imaging was 1.13 [interquartile range (IQR), 0.2]. Perfusion-weighted imaging showed no increase in perfusion, with a relative cerebral blood volume of 1.02 (IQR, 0.05) and a relative cerebral blood flow of 1.01 (IQR, 0.08). MR spectroscopy showed no abnormal peaks. Median follow-up was 2 (IQR, 1.2) years, without any changes in size. CONCLUSIONS: A comprehensive characterization protocol including advanced multiparametric magnetic resonance imaging sequences showed no imaging patterns suggestive of malignancy in MVNTs. It might be useful to better characterize MVNTs.

[Intracranial hypertension and lupus]. / Hypertension intracrânienne et lupus.

INTRODUCTION: Idiopathic intracranial hypertension (IH) occurs most commonly in women and overweight subjects. It must be reported associated to general diseases, like systemic lupus erythematosus (SLE). METHODS: We report an observation of a patient with lupus complicated by glomerulonephritis and IH. OBSERVATION: A 29 years old woman, without overweight, was followed for a SLE with skin and arthritic involvement . Four years after onset, a renal complication appeared with severe nephrotic syndrome. Six weeks after, bilateral papillar oedema was discovered, revealing an IH, as the patient was treated by oral steroids at 1mg/kg/d and bimonthly intravenous cyclophosphamide. The patient was completely asymptomatic. Brain MRI with veino-RMN was normal, without cerebral venous thrombosis. Lumbar punction showed an elevated opening pressure of 30,5 cmH(2)0 but with normal cerebrospinal fluid (CSF) contents. Evacuation of 30 mL of CSF and immunosuppressive treatment allowed symptoms regression. DISCUSSION/CONCLUSION: Twenty-seven cases of IH associated to SLE with nephritis have been reported in literature. Young women are more frequently involved with in half of cases a diffuse proliferative glomerulonephritis. Predisposing factors, like anaemia, must be associated. IH allows SLE diagnose in more than the third of the cases. Then, SLE has to be searched as an etiology of IH, in particular in non-obese patients and when nephritis is associated.

[Neurological complications of JC virus infection: A review]. / Complications neurologiques de l'infection par le virus JC : revue générale.

Although human polyomavirus JC (JCV) seroprevalence in the general population is high, its neurological complications are rare and progressive multifocal leukoencephalopathy (PML), a lethal central nervous system (CNS) demyelinating disease, is the most well-known. After an usually asymptomatic primary infection during late childhood, a latent JCV form persists in different sites, notably the kidneys and lymphocytes. Rearrangement of that archetype into the prototypical neurotropic strain can reactivate JCV, thereby enabling its CNS penetration and infection of glial cells. In a context of defective immune defenses (HIV infection, cancer or immunosuppressant therapies) this infection leads to oligodendrocyte death that contributes, via demyelinization, to PML but also, as more recently described, to other CNS complications, e.g., JCV granule cell neuronopathy, meningitis or encephalitis. Clinical manifestations depend on the localization of the lesions. The increasingly widespread use of new immunomodulatory monoclonal antibodies to treat multiple sclerosis and other inflammatory systemic diseases has increased PML frequency in those previously rarely affected entities. Diagnosis relies on magnetic resonance imaging, JCV detection in cerebrospinal fluid and, when necessary, brain histology. PML is often lethal. No specific, evidence-based treatment with clinically relevant efficacy is available. The therapeutic objective is to restore host immune responses to JCV, while avoiding immune-reconstitution inflammatory syndrome.

[Susac syndrome: study of five cases]. / Syndrome de Susac: étude de cinq cas.

INTRODUCTION: Susac syndrome is a rare microangiopathy, responsible for small cerebral, retinal and cochlear infarcts. The classic clinical triad includes multiple neurologic signs (from headaches to coma), retinal branch occlusions and sensorineural hearing loss. METHODS: We report a series of five patients with Susac syndrome followed in our department from 1997 to 2007. RESULTS: There were four women and one man (mean age at onset: 35.2 years). Clinical symptoms at onset were neurological (n=1), ophthalmological (n=1), auditory (n=1) and clinical triad (n=2). Neurologic symptoms included encephalopathy (n=2), headache (n=5), transient ischemic attacks (n=1). Brain MRI showed T2 lesions in the white and grey matter, corpus callosum and gadolinium-enhanced punctiform lesions. Cerebrospinal fluid contained an elevated protein level in three cases. Immunologic treatments (steroids [n=4], cylophosphamid [n=3], intravenous immunoglobulins [n=5]) associated with aspirin and/or oral anticoagulants, despite early relapses (n=2), led to dramatic clinical improvement (n=5). CONCLUSION: Due to its polymorphism the SS is difficult to diagnose when the clinical triad is lacking. In the absence of clinical trial and consensus treatment is empiric and based on supposed pathogenesis.

[Presentation of an assessment battery for visual mental imagery and visual perception]. / Normalisation d'une batterie d'évaluation de l'imagerie mentale visuelle et de la perception visuelle.

INTRODUCTION: The relationship between visual perception and visual mental imagery are at the center of a lively theoretical debate between those postulating common neurocognitive processes between perception and imagery and those who emphasize the differences between these two entities. Neuropsychology can make an important contribution to this debate, by assessing associations and dissociations between perceptual and imaginal deficits in patients with brain damage. However, currently there is no standardized test battery available for such assessments. MATERIAL AND METHODS: Here we present a battery of paper-and-pencil tests assessing different domains of visual mental imagery and visual perception abilities: object form and color, animals, orthographic material, numbers, faces, and space. We also explored the effects of age, educational level and gender on performance on a group of 103 participants free of neurological damage. RESULTS: The battery includes two parts: one composed of 14 tests assessing mental imagery and the second part composed of eight tests assessing the abilities of visual perception. We calculated the correlations between the tests, and found that, with the exception of orthographic material, there were generally poor correlations between imagery and perceptual tests. CONCLUSION: This result seems inconsistent with hypotheses postulating a strict correspondence between perceptual and imagery abilities.

Multinodular and Vacuolating Posterior Fossa Lesions of Unknown Significance.

Multinodular and vacuolating neuronal tumor of the cerebrum is a rare supratentorial brain tumor described for the first time in 2013. Here, we report 11 cases of infratentorial lesions showing similar striking imaging features consisting of a cluster of low T1-weighted imaging and high T2-FLAIR signal intensity nodules, which we referred to as multinodular and vacuolating posterior fossa lesions of unknown significance. No relationship was found between the location of the lesion and clinical symptoms. A T2-FLAIR hypointense central dot sign was present in images of 9/11 (82%) patients. Cortical involvement was present in 2/11 (18%) of patients. Only 1 nodule of 1 multinodular and vacuolating posterior fossa lesion of unknown significance showed enhancement on postcontrast T1WI. DWI, SWI, MRS, and PWI showed no malignant pattern. Lesions did not change in size or signal during a median follow-up of 3 years, suggesting that multinodular and vacuolating posterior fossa lesions of unknown significance are benign malformative lesions that do not require surgical intervention or removal.

[HIV and the central nervous system]. / Atteintes du système nerveux central et infection par le VIH-1.

Central nervous system complications are common in HIV-1 infected patients and occur either as a result of concomitant immunosuppression (opportunistic infections, lymphoma and tumors), as a primary manifestation of HIV infection, or as an adverse effect of therapy (immune restoration and toxicity). These complications contribute largely to patient morbidity and mortality. In the era of highly active antiretroviral therapy (HAART) these disease states have changed in presentation, outcome and incidence. We review in detail the epidemiology, pathogenesis, clinical features, diagnosis, and management of these disorders.

Reversible ALS-like disorder in HIV infection.

OBJECTIVE: To describe the clinical features, treatment, and outcome of six cases of HIV-1-associated ALS-like disorder. METHODS: The authors reviewed patients with HIV infection with neurologic symptoms seen over a 13-year period. Patients were identified by using the El Escorial research diagnostic criteria defining three categories of certainty for definite, probable, or possible ALS. Clinical features, EMG, CSF, serum analyses, and imaging and virological studies were assessed. RESULTS: Six patients with immunodepression (mean CD4(+) cells = 86.2/mm(3); mean age = 34 years) developed distal motor weakness mimicking a monomelic amyotrophy that subacutely progressed regionally or assumed a symmetric distribution on more than one region. EMG was characteristic of motor neuron disease with no multifocal conduction block. Causes other than HIV-1 were ruled out. The unusual rapid extension of the disease and the positive response to antiretroviral therapy suggest that ALS syndrome and HIV infection are etiologically related. HIV-1 might cause an ALS-like disorder by several mechanisms-via neuronal infection, by secretion of toxic viral substance, by inducing the immune system to secrete cytokines, or by inducing an autoimmune disease. CONCLUSION: These cases suggest that the association between some motor neuron diseases and HIV infection is not coincidental but pathogenetically related and that ALS-like disorder should be considered an HIV-related neurologic complication.

Neuropathy in diffuse infiltrative lymphocytosis syndrome: an HIV neuropathy, not a lymphoma.

OBJECTIVE: To determine whether CD8 lymphoid infiltrates in nerves of patients with HIV-associated diffuse infiltrative lymphocytosis syndrome (DILS) corresponds to a lymphomatous neoplastic process or to a proliferation of T cells reactional to HIV. BACKGROUND: DILS is characterized by persistent CD8 hyperlymphocytosis and multivisceral CD8 T-cell infiltration, which may affect peripheral nerves. METHODS: Presence of monoclonal T cells and HIV-1 proviral load were evaluated by polymerase chain reaction (PCR) techniques in frozen peripheral nerve samples from six patients with DILS neuropathy and 22 patients with other HIV-associated peripheral neuropathies, including mononeuritis multiplex (MM:6), inflammatory demyelinating polyneuropathies (IDP:6), distal sensory polyneuropathy (DSP:5), and toxic distal sensory polyneuropathy (TDSP:5). RESULTS: Five of six patients with DILS showed no detectable monoclonal T-cell clones in their nerves. Nerve proviral load in DILS (6.8 +/- 0.2 log/10(5) cells) was much higher than in MM (p < 0.008), IDP (p < 0.001), DSP (p < 0.001), and TDSP (p < 0.005). CONCLUSIONS: DILS neuropathy represents a separate entity among HIV-associated neuropathies. It is associated with massive HIV proviral load in nerve and must not be confused with a peripheral nerve T-cell lymphoma.

AIDS-associated progressive multifocal leukoencephalopathy revealed by new-onset seizures.

PURPOSE: To describe the clinical features of new-onset seizures in HIV-1-infected persons with progressive multifocal leukoencephalopathy (PML), and to discuss potential mechanisms. PATIENTS AND METHODS: Forty-nine consecutive HIV-1-infected patients with PML attended our institutions between January 1988 and September 1993. We retrospectively analyzed cases with seizures as the presenting symptom of PML. RESULTS: Twenty percent of the HIV-1-infected patients with PML presented with new-onset seizures of various types, generalized or partial. None of them met the criteria of the AIDS dementia complex or had a concomitant opportunistic infection. Their mean CD4 cell count was < 60/mm3. Brain magnetic resonance imaging showed areas of increased signal intensity on T2-weighted images in 9 cases, and atrophy in only 1 case. Lesions most often involved subcortical white matter in parieto-occipital or frontal lobes, but 2 patients had posterior fossa lesions. Image-guided stereotactic brain biopsies in 8 cases and postmortem examination in 2 confirmed the diagnosis of PML. Typical histological lesions were observed in all cases, and positive immunolabelling of oligodendroglial nuclei was obtained in all cases with the polyclonal antibody directed against late SV40 antigens. Putative causative factors for the seizures include demyelinated lesions adjacent to the cerebral cortex acting as irritative foci, axonal conduction abnormalities, or disturbances of the neuron-glia balance. CONCLUSION: These cases illustrate that PML should be considered as a possible cause of new-onset seizures in patients with HIV-1 infection.

[Central serotonin receptors. Principal fundamental and functional aspects. Therapeutic applications]. / Récepteurs centraux de la sérotonine. Principaux aspects fondamentaux et fonctionnels. Applications thérapeutiques.

Serotonin (5-HT) is a central neurotransmitter and a neuromodulator. This amine is involved in many physiological functions and pathological disorders. Most of its effects are mediated by specific 5-HT receptors. In the first part of this paper, the present knowledge of 5-HT receptors is reviewed in terms of both pharmacology and molecular biology. In the second part, the functional properties of 5-HT receptors are analyzed and their involvement in pathophysiological processes is discussed. Most 5-HT receptors belong to the G-protein-coupled receptor family (5-HT1, 5-HT2 and 5-HT4 receptors), whereas one is a member of the ligand-gated ion-channel receptor family (5-HT3 receptor). 5-HT1 receptors are characterized by their high affinity for 5-HT and comprise several subclasses. Most are negatively coupled to adenylate cyclase but the 5-HT1C subtype is linked to phospholipase C activation and resembles the 5-HT2 receptor. By contrast, the newly identified 5-HT4 receptor is positively coupled to adenylate cyclase. Most 5-HT receptors have now been cloned, but their physiological roles are not completely understood. Better knowledge of 5-HT receptors has already led to the development of new drugs, such as buspirone, a 5-HT1A partial agonist devoid of benzodiazepine-like properties for the treatment of generalized anxiety. Anxiolytic properties have also been reported for 5-HT2 and 5-HT3 receptor antagonists. A new and potent anti-migrainous drug, sumatriptan, has recently been selected among compounds obtained by research on the 5-HT1D receptor. This key receptor controls the release of monoamines, amino acids and peptides, and new drugs are expected in the near future. The therapeutic potential of 5-HT3 antagonists is impressive, as these compounds have potent antiemetic, promnesic and antipsychotic properties in various animal models. Two such drugs have already been marketed for the prevention of radiation-induced emesis (ondansetron and granisetron) and are more potent than the antidopaminergic drugs. Many other data suggest that 5-HT receptors might be involved in other illnesses. Some drugs are in the development phase but identification of the relevant receptor is often difficult. Furthermore, the lak of specific ligands for some receptors clearly hinders functional correlations.

[Lobar holoprosencephaly associated with heterotopic gray matter. A case disclosed in adulthood by epilepsy]. / Holoprosencéphalie lobaire associée à des hétérotopies de substance grise. Un cas révélé à l'âge adulte par une épilepsie.

A case of lobar holoprosencephaly associated with heterotopias of the grey matter is reported. The patient was a young woman whose cerebral malformation was revealed by epileptic seizures at the age of 22. There was no intellectual deficit. Computerized tomography and, chiefly, magnetic resonance imaging, enabled the study of the malformation.

[Susac's syndrome: improvement with combined cyclophosphamide and intravenous immunoglobulin therapy]. / Syndrome de Susac: un cas d'évolution favorable sous cyclophosphamide et immunoglobulines intraveineuses.

We report a case of Susac's syndrome characterized by subacute encephalopathy, bilateral hearing loss and multiple bilateral branch retinal artery occlusions in a forty-year-old-white-woman. Brain Magnetic Resonance Imaging showed on T2-weighted images multiple, punctate areas of increased signal intensity in periventricular white matter, gray matter and brainstem most of them being enhanced by gadolinium. Cerebrospinal fluid was acellular but with an increased protein level (1.66 g/l). Treatment with cyclophosphamid and intravenous immmunoglobulin resulted in dramatic improvement of the clinical status over the following months and CSF normalization.

[Sub-cortico-frontal encephalopathy and choreic movements related to recombinant interferon-alpha 2b]. / Encéphalopathie sous-cortico-frontale et mouvements choréiques liés à l'interféron-alpha 2b recombinant.

Interferon (IFN)-alpha is associated with central nervous system (CNS) side effects such as depression and suicide ideation, somnolence, confusion, drowsiness, psychomotor slowing, memory impairment and visual disorientation. More severe complications are uncommon and include frank paranoia, dementia, coma, seizures and neuropathy. With the increasing long-term and extensive use of interferon (IFN)-alpha several new neurologic adverse effects have been recognized. We report on two patients who developed severe subcortico-frontal impairment, associated in one case with choreic movements, after a long-term treatment with IFN-alpha 2b for hematologic malignancies. Our patients rapidly and completely recovered from their cognitive and motor symptoms after the discontinuation of the drug. The same neurologic symptoms reappeared when we attempted to reintroduce lower doses of IFN-alpha in one case. Although little is known regarding IFN-alpha actions in the CNS, several possible mechanisms may underlie its neurotoxicity and might result from complex direct and indirect effects involving brain vasculature, neuroendocrine system, neurotoxic secondary cytokines'release and neurotransmitters.

[Isoform 4 of apolipoprotein E and Alzheimer disease. Specificity and clinical study]. / Isoforme 4 de l'apolipoprotéine E et maladie d'Alzheimer. Spécificité et étude clinique.

We studied apolipoprotein E (apoE) phenotype in 113 patients with possible and probable Alzheimer's disease (AD), 49 patients with Parkinson's disease (including 11 patients with dementia) and 23 patients with mixed and vascular dementia. Normal controls were 498 young, healthy blood donors previously recorded. All patients were assayed for blood lipid parameters. All AD patients underwent a neuropsychological evaluation (including a mini-mental status and 5 subtests of Cole and Dastoor hierarchic dementia scale) and a detailed interrogation of them and their caregivers about their familial and personal medical history. The recorded data included age at onset, clinical subtype (i.e. amnesic or aphaso-apraxic), occurrence of fits, cases of probable dementia in relatives, and ages of their parents at death. There was a significant association between the fourth isoform of apoE and AD, as in previous works. We did not found such an association for PD patients (even with dementia) nor mixed and vascular demented patients. We failed to find any association between any clinical characteristic of the patients and the biological subgroups defined by the number of epsilon 4 alleles, except with regard for the age of onset. Surprisingly, the mothers of epsilon 4 bearers had a significantly longer life than mothers of other patients. We failed to found any significant difference of apoE2 isoform frequency between AD patients and controls. AD patients had higher levels of cholesterol and apoAl than did MP and mixed and vascular demented patients. ApoAl level is known to constitute a protective factor against coronary heart disease, which is usually increased by the presence of apoE-epsilon 4.(ABSTRACT TRUNCATED AT 250 WORDS)

[Specialized memory consultation. Value and evaluation after 2 years of functioning]. / Consultation spécialisée de la mémoire. Intérêt et bilan de 2 années de fonctionnement.

Disorders of memory are a frequent cause of consultation and are observed in dementias, in some depressive syndromes and in normal ageing. The specialized memory consultation is based on two successive examinations: one by a neurologist, the other by a psychologist, using standardized batteries of tests. In 100 consecutive subjects, 3 main groups of about 20 to 30 individuals each could be identified: dementia syndromes, psychiatric disorders and age-related disorders of memory. The remaining subjects had various diseases. In subjects with memory complaints a psychometric evaluation performed by a team of specialists seems to be the only means of refining the diagnosis enough for a personalized management. In addition, the specialized consultation team acquires the knowledge that will help it, in the future, to lay down the bases of medical prevention of pathological cerebral ageing.

[Meningoradiculitis after injection of an antirabies vaccine. A vaccine from human diploid cell culture]. / Méningo-radiculite secondaire à une vaccination antirabique. A partir d'un vaccin préparé sur culture de cellules diploïdes humaines.

We report the case of a 45-year old farmer who developed meningoradiculitis after preventive anti-rabies vaccination with a vaccine obtained from human diploid cell culture. Two weeks after the second injection of vaccine, the patient complained of sensory symptoms in the right half of his body. These symptoms spontaneously regressed. The literature is reviewed and the physiopathological hypotheses are discussed.

[Cerebral glioblastoma: a new complication of HIV-1 infection]. / Glioblastome cérébral: nouvelle complication de l'infection par le VIH 1.

A new case of supratentorial malignant glioma is reported in an HIV-1 infected male homosexual. Tumours of the nervous system account for only 5 to 10 percent of neurological complications of AIDS, and most of them are lymphomas or metastases from Kaposi's sarcomas. In fact, HIV-1 is a neurotropic lentivirus, not transforming by definition. Our patient had a frontal tumoral syndrome resistant to the conventional anti-toxoplasmic treatment. Pathological examination of a tumoral fragment obtained by stereotactic biopsy showed that according to the WHO criteria the tumour was a glioblastoma. The mechanism through which HIV infection results in malignant transformation of astrocytes is conjectural. There is no consensus on whether the virus is located in glial cells, but the transgenic animal technique suggests that the tat gene might play a certain role. Other hypotheses concerning the indirect neurotoxicity of HIV have been put forward, notably that of viral coinfection with viruses of the papova group.