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Biomedical subjects

F Andermann

Publications and source records attributed to F Andermann.

At least 109 records · Page 6Linked to original sources
PubMed1998

Familial alternating epilepsia partialis continua with chronic encephalitis: another variant of Rasmussen syndrome?

Two brothers had infantile epilepsia partialis continua alternately involving both sides of the body. The children rapidly developed severe psychomotor regression and cerebral atrophy. A brain biopsy specimen showed evidence of chronic inflammatory changes. Extensive investigation did not provide evidence of a specific viral pathogenesis, mitochondrial disorder, or any identifiable neurodegenerative genetically determined disorder. This illness has the features of Rasmussen chronic encephalitis, in which bilateral involvement is quite unusual. Although few patients with bilateral hemispheral involvement have been described, to our knowledge there have been no reported cases involving affected siblings. The familial disorder described herein may represent yet another variant of the classically sporadic and unilateral childhood form. This group of disorders is probably immunologically determined.

Child, Preschool↗
PubMed1998

Autosomal dominant nocturnal frontal-lobe epilepsy: genetic heterogeneity and evidence for a second locus at 15q24.

Autosomal dominant nocturnal frontal-lobe epilepsy (ADNFLE) is a recently identified partial epilepsy in which two different mutations have been described in the alpha4 subunit of the neuronal nicotinic acetylcholine receptor (CHRNA4). An additional seven families are presented in which ADNFLE is unlinked to the CHRNA4 region on chromosome 20q13.2. Seven additional sporadic cases showed no evidence of defective CHRNA4. One of the families showed evidence of linkage to 15q24, close to the CHRNA3/CHRNA5/CHRNB4 cluster (maximum LOD score of 3.01 with D15S152). Recombination between ADNFLE and CHRNA4, linkage to 15q24 in one family, and exclusion from 15q24 and 20q13.2 in others demonstrate genetic heterogeneity with at least three different genes for ADNFLE. The CHRNA4 gene and the two known CHRNA4 mutations are responsible for only a minority of ADNFLE. Although the ADNFLE phenotype is clinically homogeneous, there appear to be a variety of molecular defects responsible for this disorder, which will provide a challenge to the understanding of the basic mechanism of epileptogenesis.

Chromosome Mapping↗
PubMed1998

Complex visual hallucinations. Clinical and neurobiological insights.

Complex visual hallucinations may affect some normal individuals on going to sleep and are also seen in pathological states, often in association with a sleep disturbance. The content of these hallucinations is striking and relatively stereotyped, often involving animals and human figures in bright colours and dramatic settings. Conditions causing these hallucinations include narcolepsy-cataplexy syndrome, peduncular hallucinosis, treated idiopathic Parkinson's disease, Lewy body dementia without treatment, migraine coma, Charles Bonnet syndrome (visual hallucinations of the blind), schizophrenia, hallucinogen-induced states and epilepsy. We describe cases of hallucinosis due to several of these causes and expand on previous hypotheses to suggest three mechanisms underlying complex visual hallucinations. (i) Epileptic hallucinations are probably due to a direct irritative process acting on cortical centres integrating complex visual information. (ii) Visual pathway lesions cause defective visual input and may result in hallucinations from defective visual processing or an abnormal cortical release phenomenon. (iii) Brainstem lesions appear to affect ascending cholinergic and serotonergic pathways, and may also be implicated in Parkinson's disease. These brainstem abnormalities are often associated with disturbances of sleep. We discuss how these lesions, outside the primary visual system, may cause defective modulation of thalamocortical relationships leading to a release phenomenon. We suggest that perturbation of a distributed matrix may explain the production of similar, complex mental phenomena by relatively blunt insults at disparate sites.

Brain Diseases↗
PubMed1998

Spectroscopic imaging of frontal neuronal dysfunction in hyperekplexia.

We used proton magnetic resonance spectroscopic imaging (MRSI) to assess in vivo cortical neuronal involvement in hyperekplexia. Cerebral neuronal function was measured using proton MRSI in four unrelated patients with hyperekplexia and 20 healthy controls. All patients had the major form of hyperekplexia, with additional atypical clinical features in two of them. Family history was positive in three patients and absent in one. The neuronal marker N-acetylaspartate (NAA), choline-containing compounds (Cho) and creatine (Cr) were measured in frontal, central and parietal areas. The MRSI showed a reduction of the relative resonance intensity of NAA/(Cr + Cho) in frontal and central regions in three patients, and in the right frontal region of the fourth. In one patient a second MRSI showed normal relative NAA resonance intensities over both temporal lobes as well as in the brainstem. In two subjects the topography of EEG abnormalities in the frontal lobes coincided with the MRSI findings. This proton MRSI study indicates the presence of frontal neuronal dysfunction in hyperekplexia. Whether this represents cortical dysfunction or an epiphenomenon of diencephalic or brainstem abnormalities remains open. However, the observation of normal proton MRSI in the temporal regions and brainstem in one of the patients seems to concur with the hypothesis of a facilitatory role of cortical dysfunction within areas of sensorimotor representation in the generation of the pathological startle reaction in hyperekplexia.

Adolescent↗
PubMed1998

Mutations in the palmitoyl-protein thioesterase gene (PPT; CLN1) causing juvenile neuronal ceroid lipofuscinosis with granular osmiophilic deposits.

A subtype of neuronal ceroid lipofuscinosis (NCL) is well recognized which has a clinical course consistent with juvenile NCL (JNCL) but the ultrastructural characteristics of infantile NCL (INCL): granular osmiophilic deposits (GROD). Evidence supporting linkage of this phenotype, designated vJNCL/GROD, to the INCL region of chromosome 1p32 was demonstrated (pairwise lod score with D1S211 , Z max = 2.63, straight theta = 0.00). The INCL gene, palmitoyl-protein thioesterase (PPT ; CLN1), was therefore screened for mutations in 11 vJNCL/GROD families. Five mutations in the PPT gene were identified: three missense mutations, Thr75Pro, Asp79Gly, Leu219Gln, and two nonsense mutations, Leu10STOP and Arg151STOP. The missense mutation Thr75Pro accounted for nine of the 22 disease chromosomes analysed and the nonsense mutation Arg151STOP for seven. Nine out of 11 patients were shown to combine a missense mutation on one disease chromosome with a nonsense mutation on the other. Mutations previously identified in INCL were not observed in vJNCL/GROD families. Thioesterase activity in peripheral blood lymphoblast cells was found to be markedly reduced in vJNCL/GROD patients compared with controls. These results demonstrate that this subtype of JNCL is allelic to INCL and further emphasize the correlation which exists between genetic basis and ultrastructural changes in the NCLs.

Age of Onset↗
PubMed1998

Case study: neurological brain waves causing serious behavioral brainstorms.

A case highlighting the association of epilepsy with psychopathology is reported. The patient suffered a rare and extreme behavioral disturbance, characterized by persistent disruptive behavior and intermittent bizarre and violent outbursts. These outbursts often appeared purposeful, but some of them were later diagnosed as ictal manifestations of temporal lobe epilepsy. Temporal lobectomy resulted in remission both of the epilepsy and of the more persistent behavioral disturbance. lctal behavioral change was masked by interictal behavioral disturbance, leading to delayed diagnosis and prolonged psychosocial dysfunction. It is important to record the paroxysmal abnormal behavior with simultaneous electroencephalographic recording if there is a suspicion of organic disease. Physical and psychosocial factors in the relationship between epilepsy and extreme psychiatric disturbance are considered. This case demonstrates how successful epilepsy treatment may produce amelioration of associated psychiatric disturbance.

Attention Deficit and Disruptive Behavior Disorder↗
PubMed1998

Morphometric analysis of the temporal lobe in temporal lobe epilepsy.

PURPOSE: Using high-resolution magnetic resonance imaging (MRI), we examined the temporal neocortex and the underlying white matter in patients with unilateral temporal lobe epilepsy (TLE) and in control subjects. METHODS: The images of 27 patients and 42 control subjects were registered into stereotaxic space, corrected for image intensity inhomogeneity, and automatically segmented into gray matter, white matter, and cerebrospinal fluid (CSF) over a predetermined extent of the temporal lobe. The surface between the gray matter and CSF was extracted, indices of curvature (IOC) of the surface were calculated, and a frequency histogram of the IOC was obtained. RESULTS: There was significant bilateral reduction in the total volume of the temporal lobe and in the volume of gray matter. White matter volume was significantly reduced only in the temporal lobe ipsilateral to the seizure focus. There were significant changes in the position and amplitude of peaks in the frequency histogram of the IOC. CONCLUSIONS: The volume of gray matter was negatively correlated with duration of epilepsy, suggesting that neocortical changes may be a consequence of seizures. Changes in the frequency histogram of the IOC suggested an additional alteration in the surface morphology of the temporal lobe in TLE, possibly related to sulcal widening.

Adolescent↗
PubMed1998

Continuous unilateral epileptiform discharge and language delay: effect of functional hemispherectomy on language acquisition.

PURPOSE: To assess the efficacy of functional hemispherectomy in promoting language acquisition in a child with severe language delay and continuous left hemispheric epileptiform discharge in the absence of clinical seizures. We report a 6-month-old girl who initially presented with a right hemiparesis secondary to a lesion of probable prenatal origin in the distribution of the left middle cerebral artery. Weeks later, she developed infantile spasms. At 1.5 years of age, because of intractable seizures, the patient had fenestration of the left porencephalic cyst and anterior temporal lobectomy. The seizures ceased; however, language development remained limited to 35 words at 3.5 years of age. The EEG showed almost continuous epileptiform activity over the left hemisphere with no independent epileptiform potentials contralaterally. She underwent a functional left hemispherectomy. METHODS: Imaging, electroencephalographic investigation, pre- and postoperative psychological and speech assessment were carried out. RESULTS: Considerable language, speech, and behavior improvement was noted within 2 months of surgery. CONCLUSIONS: Interictal epileptiform discharges can interfere with the development of contralateral hemispheric function in the absence of clinical seizures. Early functional hemispherectomy may have a role in promoting optimal language development in appropriately selected patients. Although the primary indication for functional hemispherectomy is to control intractable seizures, a secondary proposed indication is to reduce functional impairment of the other hemisphere by electrical interference.

Brain↗
PubMed1998

Proton magnetic resonance spectroscopic imaging in patients with extratemporal epilepsy.

PURPOSE: Reduced levels of N-acetylaspartate (NAA) in temporal lobes responsible for temporal lobe epilepsy have been observed consistently in proton magnetic resonance spectroscopy (MRS) studies. METHODS: We investigated the potential of proton MRS to detect low NAA outside of the temporal lobes in patients with non-lesional partial extratemporal epilepsy. Proton MR spectroscopic imaging (MRSI) data of both frontal lobes and central/postcentral regions were obtained in 20 such patients and 16 normal control subjects. The epileptogenic region was determined by an extensive clinical-EEG investigation, including the recording of habitual seizures in each patient, and intracranial EEG recordings in 10 patients. RESULTS: The relative NAA resonance intensities (i.e., NAA/phosphocreatine plus creatine (CR(t)), NAA/choline-containing metabolites (Cho(t)) and NAA/Cr(t) + Cho(t)), were all significantly reduced throughout the spectroscopic image as compared with that of the controls. Furthermore, reduction of the NAA ratios was greater in the epileptogenic region as compared with the nonepileptogenic regions, on EEG investigation. CONCLUSIONS: In vivo proton MRSI of patients with nonlesional partial extratemporal epilepsy detected evidence of widespread neuronal damage or dysfunction that was greatest in the region of seizure focus.

Adult↗
PubMed1998

Celiac disease, bilateral occipital calcifications and intractable epilepsy: mechanisms of seizure origin.

PURPOSE: To elucidate the mechanisms of seizure origin in patients with celiac disease and bilateral occipital calcifications (CEBOC). Individuals with CEBOC frequently present with occipital lobe seizures, but additional lesions and additional attack patterns may occur. METHODS: We studied two men and one woman who had CEBOC. Villous atrophy was revealed in the two patients who underwent duodenal biopsy. All had a comprehensive presurgical evaluation, including prolonged video-EEG recordings. Two had magnetic resonance imaging (MRI) with volumetric study of mesial temporal structures (MRIV). One patient had undergone stereotactic intracranial depth electrode studies (SEEG). RESULTS: All patients presented with intractable complex partial seizures. Two had partial simple seizures with visual aura. Neurologic examination was normal; one was of normal intelligence, and two were mildly retarded. Neuroimaging studies showed that each had bilateral occipital calcifications as well as epileptiform abnormalities over temporal lobes. In one, MRI showed an additional right frontal lesion, but SEEG demonstrated right occipital lobe seizure origin with anterior spread; this male patient later underwent a right occipital lobe resection. Another with a history of prolonged febrile convulsions had bilateral hippocampal and amygdalar atrophy demonstrated by MRIV. CONCLUSIONS: In one patient, SEEG confirmed that seizures originated in the occipital lobe. The presence of dual pathology was demonstrated in another, raising the possibility of both occipital and temporal seizure onset. The presence of extraoccipital lesions or of mesial temporal atrophy requires SEEG for clarification of seizure onset. In the absence of confounding factors and when laterality can be demonstrated, surgical treatment may be considered.

Adult↗
PubMed1998

The benign occipital epilepsies of childhood: an overview of the idiopathic syndromes and of the relationship to migraine.

Benign occipital epilepsy of childhood is an idiopathic partial epilepsy syndrome with elementary visual symptomatology, frequently associated with other ictal phenomena. Seizures are usually followed by postictal headache and are often associated with interictal occipital rhythmic paroxysmal EEG activity that appears only after eye closure. In some children the ictal visual symptoms or the interictal EEG abnormalities may not be demonstrated. The clinical and/or EEG manifestations of other forms of idiopathic partial or generalized epilepsy may be found in association. Occipital spikes in non-epileptic children with defective vision, occipital slow spike-and-wave found in some patients with the Lennox-Gastaut syndrome, focal epilepsy due to occipital lesions, seizures originating in the temporal lobe secondary to an occipital abnormality, and complicated or basilar migraine must be considered in the differential diagnosis. Early-onset benign occipital epilepsy or seizure susceptibility syndrome deserves to be considered separately. It has been defined by Panayiotopoulos as consisting of brief, infrequent attacks or prolonged status epilepticus and characterized by ictal deviation of the eyes and/or head and vomiting, occurring in children usually between the ages of 3 and 7 years. Advances in molecular genetics will help decide whether these two disorders are indeed distinct. Benign occipital and benign rolandic epilepsy are commonly associated with migraine. The selective involvement of the occipital lobe in migraine has not been fully explained. The association between benign occipital epilepsy and migraine is likely related to this underlying mechanism as well. The "fixation off" phenomenon or blocking of occipital epileptic discharges by eye opening is not specific to benign occipital epilepsy of childhood and may be found in symptomatic epilepsies as well. Migraine and epilepsy are distinct disorders, both as far as their pathophysiologic mechanisms and clinical symptomatology are concerned. There is however an overlap in some patients and a causal relationship may exist in some, leading to clinically distinct migraine epilepsy syndromes. Here too, clarification of the molecular basis of migraine and of epilepsy will throw light on the nature of the relationship between the two conditions.

Adolescent↗
PubMed1998

Anticipation in familial cavernous angioma: ascertainment bias or genetic cause.

OBJECTIVES: Anticipation has been linked to unstable trinucleotide repeats in many neurological disorders. We examined the hypothesis of genetic anticipation in familial cavernous angioma (FCA) of the central nervous system. MATERIAL AND METHODS: The mean ASO of affected individuals was compared between successive generations in 55 families. Intergenerational pair-wise comparisons were employed to avoid several ascertainment biases. Regarding severity of disease both type of manifestation and number of cavernous angiomas were compared between generations. RESULTS: The mean ASO decreased significantly both from the first to the second generation (31.6 vs 17.8 years; P = 0.000) and from the second to the third generation (17.8 vs 6.7 years; P = 0.002). The pair-wise comparisons also showed significantly earlier ASO. No clear evidence for anticipation with regard to severity of disease was found. CONCLUSIONS: Molecular genetic studies will determine whether trinucleotide repeats are the underlying mechanism for our observation of anticipation in FCA.

Adolescent↗
PubMed1998

Cortical dysplasia: an immunocytochemical study of three patients.

Human cortical dysplastic lesions are frequently associated with severe partial epilepsies. We report an immunocytochemical investigation on cortical tissue from three surgically treated patients, 20, 38, and 14 years old, with intractable epilepsy due to cortical dysplasia. The studies were performed using antibodies recognizing cytoskeletal proteins, calcium-binding proteins, and some subunits of glutamate receptors. The specimens from the three patients displayed common features: (1) focal cytoarchitectural abnormalities with an increased number of giant pyramidal neurons through all cortical layers except layer I; (2) large, round-shaped balloon cells mainly concentrated in the deepest part of the cortex and in the white matter; (3) a decrease of calcium binding protein immunopositive gamma-aminobutyric acid (GABA)ergic neurons; and (4) abnormal baskets of parvalbumin-positive terminals around the excitatory (pyramidal and large, round-shaped) neurons. These data provide evidence that the epileptogenicity in these types of cortical dysplasia is due to an increase in excitatory neurons coupled with a decrease in GABAergic interneurons.

Adolescent↗
PubMed1998

Familial temporal lobe epilepsy: a clinically heterogeneous syndrome.

We describe the clinical characteristics of a group of patients with familial temporal lobe epilepsy (TLE) in 11 kindreds with 36 affected individuals identified and investigated at the Montreal Neurological Hospital. Seizure types were simple partial (n = 20), complex partial (n = 29), and rare generalized tonic-clonic. Simple and complex partial seizures were infrequent or well controlled by anticonvulsant medication in 17 of 29 patients (59%) and without optimal response to medical therapy in 12 of 29 patients (41%). Pedigree analysis suggested autosomal dominant inheritance with incomplete penetrance. The syndrome of familial TLE has heterogeneous clinical manifestations and is not always benign.

Adolescent↗
PubMed1998

Double pathology in Rasmussen's syndrome: a window on the etiology?

The syndrome of chronic encephalitis with epilepsy (Rasmussen's syndrome) typically occurs in children and is characterized by the development of intractable focal seizures, progressive hemiparesis and intellectual deterioration. The etiology is unknown, and the pathological abnormalities vary from those of active disease, with numerous microglial nodules, with or without neuronophagia, perivascular round cells and glial scarring, to those of remote disease, demonstrated by neuronal loss, gliosis and perivascular round cells but few microglial nodules. We describe five patients presenting with clinical features typical of Rasmussen's syndrome, in whom pathological examination showed a second, previously unsuspected pathology in addition to the changes of chronic encephalitis. Two of the patients had vascular abnormalities bearing some resemblance to cavernous angiomata, one had a tumor, one had tuberous sclerosis, and one the forme fruste of tuberous sclerosis. The coexistence of a second pathology in these patients may provide information about the underlying mechanism of this rare condition.

Adolescent↗
PubMed1998

Neuronal metabolic dysfunction in patients with cortical developmental malformations: a proton magnetic resonance spectroscopic imaging study.

Cortical developmental malformations are best diagnosed by MRI and are often the cause of refractory epilepsy. Little is known about the metabolic cell function on MR spectroscopy of these types of brain anomaly. We studied 23 patients with cortical developmental malformations and refractory epilepsy using proton MR spectroscopic imaging. Mean age was 28 years (range, 9 to 47 years). The lesions examined were focal cortical dysplasia (n = 5), heterotopia (four band, six periventricular, two subcortical), polymicrogyria (n = 3), tuberous sclerosis (n = 2), and polymicrogyria and periventricular nodular heterotopia (n = 1). We measured the relative signal intensity of N-acetylaspartate/creatine (NAA/Cr) in the lesion, in the perilesional region, and in the region remote from the visible lesion. The values were compared with those from similar brain regions of 25 normal control subjects. The mean NAA/Cr z score values for the 23 patients were as follows: lesion, -2.20 +/- 0.32 (mean +/- SE), n = 21; perilesional region, -1.01 +/- 0.38, n = 15; and distant region, -0.03 +/- 0.34, n = 18 (p < 0.0002). Despite the presence of a large number of neurons, heterotopia showed a relative decrease of NAA in some patients, suggesting that the neurons present were dysfunctional. The maximal NAA/Cr decrease, indicating metabolic dysfunction, colocalized to the structural malformation as defined by MRI and extended to normal-appearing regions adjacent to the visible lesion.

Adolescent↗