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Biomedical subjects

F Andermann

Publications and source records attributed to F Andermann.

At least 19 recordsLinked to original sources
PubMed2003

Magnetic resonance spectroscopy and imaging of the thalamus in idiopathic generalized epilepsy.

Experimental work in animal models of generalized epilepsy and clinical data in humans with idiopathic generalized epilepsy (IGE) indicate that the thalamo-cortical circuitry is involved in the generation of epileptic activity. The purpose of this study was to evaluate in vivo the chemical and structural integrity of the thalamus in patients with IGE. Thalamic proton magnetic resonance spectroscopic imaging (1H-MRSI), measuring N-acetylaspartate (NAA), choline-containing compounds and creatine (Cr) was performed in 20 IGE patients and in a group of age-matched healthy subjects. Additionally, 1H-MRSI measurements were taken in the insular cortex, the posterior temporal lobe white matter and the splenium of the corpus callosum. MRI volumetric analysis of the thalamus was performed in all patients. At the time of the examination, seizures were well controlled in 10 IGE patients and poorly controlled in nine. One patient was newly diagnosed and had the MRI and MRSI examination prior to starting the antiepileptic medication. In IGE patients, 1H-MRSI showed a reduction of mean thalamic NAA/Cr compared with normal controls; no difference was found in NAA/Cr in the other examined areas. There was no difference in NAA/Cr between patients whose seizures were well controlled and those in whom seizures were not controlled. There was no correlation between thalamic NAA/Cr and mean number of spike and wave complexes. We found a significant negative correlation between thalamic NAA/Cr and duration of epilepsy. The mean thalamic volume in patients with IGE was not different from normal controls. These results show evidence of progressive thalamic neuronal dysfunction in patients with IGE supporting the notion of abnormal thalamo-cortical circuitry as a substrate of seizure generation in this form of epilepsy. The thalamic dysfunction may occur regardless of amount of spike and wave activity.

Adult↗
PubMed2003

Intractable temporal lobe epilepsy with rare spikes is less severe than with frequent spikes.

OBJECTIVE: To analyze clinical, electrophysiologic, and neuroradiologic characteristics of a group of patients with nonlesional intractable temporal lobe epilepsy (TLE) and rare or absent interictal epileptiform abnormalities (IEA). METHODS: Between 1990 and 2000, 31 patients (11 men; mean +/- SD age 34.3 +/- 11.7 years) with nonlesional intractable TLE were consecutively selected on the basis of the absence or paucity of IEA (<1/h) on serial scalp EEG recording; these were defined as "oligospikers." The clinical and laboratory characteristics of oligospikers were compared with those of a group of 27 age-matched control subjects (10 men; mean +/- SD age 38.5 +/- 11 years), randomly selected from a pool of patients with nonlesional TLE with frequent IEA. RESULTS: Oligospikers showed a later age at seizure onset (mean +/- SD 19.1 +/- 14.4 versus 10.2 +/- 7.4 years; p = 0.004), lower monthly frequency of complex partial seizures (median 6 versus 12; p = 0.035), lower incidence of secondarily generalized tonic-clonic seizures (10 versus 81%; p < 0.001), and no status epilepticus (0 versus 22%) than control subjects. Also, hippocampal atrophy (HA) was less commonly found in oligospikers (55 versus 96%; p = 0.001). However, there were no differences between the two groups in the frequency of family history of epilepsy, risk factors, febrile convulsions, and type of medication. Twenty-three (74%) oligospikers and 25 (93%) control patients underwent either a selective amygdalohippocampectomy or corticoamygdalohippocampectomy. Excellent surgical outcome (Engel's Class Ia) was found in 14 of 23 (61%) oligospikers and 17 of 25 (67%) control patients. CONCLUSIONS: This study identified a subgroup of patients with nonlesional intractable TLE with no or few IEA. Oligospikers have a later age at seizure onset, less frequent and less severe seizures, besides a lower incidence of HA. The similarity of etiologic factors compared with patients with frequent IEA suggests that the rarity of spikes could reflect a disease not really distinct but less severe, even though still intractable and incapacitating enough to consider surgery. In spite of the absence or paucity of IEA, oligospikers have excellent surgical outcome.

Adult↗
PubMed2003

Alpha-[11C] methyl-L-tryptophan and glucose metabolism in patients with temporal lobe epilepsy.

OBJECTIVE: To determine whether metabolism in the brain serotonergic system, including the kynurenine pathway, is involved in temporal lobe epilepsy (TLE). METHODS: The authors studied 14 patients with intractable TLE by PET using alpha-[11C] methyl-L-tryptophan (alpha-MTrp) and 2-[18F]-fluoro-deoxy-glucose (FDG) and compared results with 21 healthy control subjects who had alpha-MTrp PET studies. Seven patients had unilateral hippocampal atrophy (HA), and seven had normal hippocampal volumes (NV). The regional uptake constant (K*) for alpha-MTrp and regional FDG uptake were calculated in regions with high serotonergic innervation, including the hippocampus, amygdala, lateral temporal lobe, frontal lobe, thalamus, lenticular nucleus, and cingulate cortex. RESULTS: A significant increase of alpha-MTrp uptake was observed in the hippocampus ipsilateral to the seizure focus in seven TLE patients with NV compared to seven patients with HA as well as to healthy controls. In patients with TLE, glucose utilization in the lateral temporal lobe ipsilateral to the seizure focus was correlated negatively with K* for alpha-MTrp in the ipsilateral hippocampus and positively with K* in the ipsilateral lenticular nucleus and cingulate cortex. Glucose utilization in the frontal lobe ipsilateral to the seizure shows a reduction in the glucose utilization which relates to the increase in the alpha-MTrp uptake in the ipsilateral lateral temporal lobe. CONCLUSION: This study demonstrates dysfunction of the serotonergic system, which could include metabolism through the kynurenine pathway in TLE patients with normal hippocampal volumes. alpha-MTrp PET studies might be useful for lateralizing the epileptic focus in TLE patients with normal hippocampal volumes.

Adolescent↗
PubMed2003

Hippocampal atrophy and T2-weighted signal changes in familial mesial temporal lobe epilepsy.

OBJECTIVE: To correlate the clinical phenotype with hippocampal volumes (HcVs) and signal changes in patients with familial mesial temporal lobe epilepsy (FMTLE). METHODS: FMTLE was defined when at least two first-degree relatives in a family had a clinical-EEG diagnosis of MTLE. Hippocampal formation measurements were performed using 1- to 3-mm coronal T1-weighted MRIs. The presence of hyperintense T2 signal was evaluated by visual analysis. For statistical analyses, analysis of variance, chi(2) test, and regression analysis were used. RESULTS: A total of 142 patients from 45 unrelated families were studied: 113 individuals with MTLE (80 with good seizure control) and 29 family members with other seizure types. There were 99 patients (69.7%) with hippocampal atrophy (HA). Sixty-seven of the 99 patients with HA also had a hyperintense T2 signal. Hyperintense T2 signal was associated with more severe HA (p = 0.04). Patients with refractory FMTLE had more frequent HA (p = 0.03) and hyperintense T2 signal (p = 0.004) and more severe atrophy (p < 0.0001). Duration of epilepsy correlated with HcV asymmetry index (r(2) = 0.12, p = 0.00008) and with the more atrophic hippocampi but not with contralateral hippocampi. CONCLUSION: In familial mesial temporal lobe epilepsy, seizure severity is variable in affected individuals. Hippocampal atrophy was present in 70% of these patients and 69% of these had an associated hyperintense T2 signal. Although hippocampal atrophy associated with abnormal T2 signal was more frequent and more severe in patients with poor seizure control, it was also frequent in affected individuals across families. These observations suggest that one or more genes resulting in familial mesial temporal lobe epilepsy predisposes both to the clinical features of mesial temporal lobe epilepsy and to the development of hippocampal sclerosis.

Adolescent↗
PubMed2003

Mesial temporal damage in temporal lobe epilepsy: a volumetric MRI study of the hippocampus, amygdala and parahippocampal region.

Despite neuropathological and electrophysiological evidence for the involvement of parahippocampal structures in temporal lobe epilepsy (TLE), little attention has been paid to morphometric measurements of these structures in patients with TLE. Using high resolution MRI, we previously showed that the volume of the entorhinal cortex was decreased in patients with TLE. The purpose of this study was: (i) to determine whether changes in the volume of the perirhinal cortex and posterior parahippocampal cortex were detectable by MRI; and (ii) to study the distribution and degree of atrophy in mesial temporal structures including the hippocampal head, body and tail, amygdala, entorhinal cortex, perirhinal cortex and posterior parahippocampal cortex. MRI volumetric analysis was performed using a T(1)-weighted three-dimensional gradient echo sequence in 20 healthy subjects and 25 TLE patients with intractable TLE. In patients with either left or right TLE, the hippocampal head, body and tail and the entorhinal and perirhinal cortices ipsilateral to the seizure focus were significantly smaller than in normal controls. The mean volume of the posterior parahippocampal cortex was not different from that of normal controls. Within the hippocampus, the hippocampal head was more atrophic than the hippocampal body and hippocampal tail. Within the parahippocampal region, the entorhinal cortex was more severely affected than the perirhinal cortex. Our MRI results confirm pathological findings of damage in the mesial temporal lobe, involving not only the hippocampus and the amygdala, but also the entorhinal and perirhinal cortices. The pattern of atrophy may be explained by cell loss secondary to a disruption of entorhinal-hippocampal connections as a result of privileged electrical dialogue between these two structures.

Adolescent↗
PubMed2003

Genetic mapping of a new Lafora progressive myoclonus epilepsy locus (EPM2B) on 6p22.

BACKGROUND: Lafora disease is a progressive myoclonus epilepsy with polyglucosan accumulations and a peculiar neurodegeneration with generalised organellar disintegration. It causes severe seizures, leading to dementia and eventually death in early adulthood. METHODS: One Lafora disease gene, EPM2A, has been identified on chromosome 6q24. Locus heterogeneity led us to search for a second gene using a genome wide linkage scan in French-Canadian families. RESULTS: We mapped a second Lafora disease locus, EPM2B, to a 2.2 Mb region at 6p22, a region known to code for several proteins, including kinesins. Kinesins are microtubule dependent motor proteins that are involved in transporting cellular components. In neurones, they play a major role in axonal and dendritic transport. CONCLUSION: Analysis of the present locus in other non-EPM2A families will reveal whether there is further locus heterogeneity. Identification of the disease gene will be of major importance towards our understanding of the pathogenesis of Lafora disease.

Chromosome Mapping↗
PubMed2002

Resection of the lesion in patients with hypothalamic hamartomas and catastrophic epilepsy.

BACKGROUND: Patients with hypothalamic hamartomas (HH) often have severe refractory epilepsy, incapacitating behavioral abnormalities, and cognitive decline. Attempts to control the seizure disorder by resection of apparently epileptogenic mesial temporal or other cortical structures have failed consistently. OBJECTIVE: To report a series of 13 patients in whom the hamartoma itself was resected. METHODS: All patients underwent preoperative evaluation between ages 2 and 33 years and had subtotal or complete resection of the hamartoma. Follow-up ranged from 1 to 5.5 years (mean: 2.8 y). RESULTS: Preoperatively, all patients had variable combinations of gelastic, complex partial, and generalized seizures. Eight had drop attacks. In addition, all had marked behavior abnormalities and cognitive impairment. Postoperatively, two patients are completely seizure-free and 11 are either seizure-free or have achieved a greater than 90% reduction of drop attacks and generalized tonic-clonic seizures. However, minor gelastic, complex partial, and atypical absence seizures have persisted in 11 patients, although at significantly reduced rates. In addition, there has been a dramatic improvement in behavior and cognition. Three patients had an anterior thalamic and one a capsular infarct, which left only minimal long-term deficits. Exact location of the lesion in relation to the interpeduncular fossa and the walls of the third ventricle correlated with extent of excision, seizure control, and complication rate. CONCLUSION: Resection can alleviate both the seizures and the behavioral and cognitive abnormalities of hypothalamic hamartomas, but complications are frequent.

Adolescent↗
PubMed2001

Localizing value of alpha-methyl-L-tryptophan PET in intractable epilepsy of neocortical origin.

BACKGROUND: [(11)C] alpha-methyl-L-tryptophan (alpha-MTrp) has been developed as a tracer for the study of the synthesis of serotonin in the brain with PET. However, it has been shown that in pathologic conditions the tracer may reflect the activation of kynurenine metabolism. Increased levels of serotonin and quinolinic acid have been described in resected epileptogenic cortex, raising the possibility that alpha-MTrp can localize seizure foci in patients with intractable partial epilepsy. The authors assessed the uptake of alpha-MTrp in 18 patients (11 men, mean +/- SD age 27.1 +/- 10.1 years, range 13 to 54) with intractable partial epilepsy to correlate the PET findings with the epileptogenic area defined by electroclinical and neuroimaging data. METHOD: Seven patients with cortical dysplasia (CD) and 11 with partial epilepsy in which conventional MRI and fluorine-18-deoxyglucose ((18)FDG)-PET studies failed to detect any abnormality were studied. All underwent scalp EEG monitoring during the PET scan to exclude ictal events and estimate the interictal epileptic activity. RESULTS: In seven patients (39%; CD four and cryptogenic partial epilepsy three), PET showed focal increased uptake of alpha-MTrp corresponding to the epileptogenic area. alpha-MTrp uptake in the epileptic focus correlated with the frequency of interictal spikes (r = 0.7, p < 0.05). CONCLUSIONS: alpha-MTrp-PET may be of value in the localization of the epileptogenic area not only in patients with visible dysplastic lesions, but also in those with cryptogenic partial epilepsy.

Adolescent↗
PubMed2001

Benign nocturnal alternating hemiplegia of childhood: six patients and long-term follow-up.

Benign familial nocturnal alternating hemiplegia of childhood refers to recurrent attacks of hemiplegia arising from sleep, described in young children without neurologic or mental impairment. It is probably migraine related. The authors report two unrelated patients with nocturnal attacks starting at 22 and 31 months, followed by daytime episodes in one. The authors confirm the benign course of this disorder. It is distinct from the classic malignant form of alternating hemiplegia of childhood.

Child↗
PubMed2001

Mutations in the X-linked filamin 1 gene cause periventricular nodular heterotopia in males as well as in females.

Periventricular heterotopia (PH) is a human neuronal migration disorder in which many neurons destined for the cerebral cortex fail to migrate. Previous analysis showed heterozygous mutations in the X-linked gene filamin 1 (FLN1), but examined only the first six (of 48) coding exons of the gene and hence did not assess the incidence and functional consequences of FLN1 mutations. Here we perform single-strand conformation polymorphism (SSCP) analysis of FLN1 throughout its entire coding region in six PH pedigrees, 31 sporadic female PH patients and 24 sporadic male PH patients. We detected FLN1 mutations by SSCP in 83% of PH pedigrees and 19% of sporadic females with PH. Moreover, no PH females (0/7 tested) with atypical radiographic features showed FLN1 mutations, suggesting that other genes may cause atypical PH. Surprisingly, 2/24 males analyzed with PH (9%) also carried FLN1 mutations. Whereas FLN1 mutations in PH pedigrees caused severe predicted loss of FLN1 protein function, both male FLN1 mutations were consistent with partial loss of function of the protein. Moreover, sporadic female FLN1 mutations associated with PH appear to cause either severe or partial loss of function. Neither male could be shown to be mosaic for the FLN1 mutation in peripheral blood lymphocytes, suggesting that some neurons in the intact cortex of PH males may be mutant for FLN1 but migrate adequately. These results demonstrate the sensitivity and specificity of DNA testing for FLN1 mutations and have important functional implications for models of FLN1 protein function in neuronal migration.

Abnormalities, Multiple↗
PubMed2001

Entorhinal cortex atrophy in epilepsy patients exhibiting normal hippocampal volumes.

OBJECTIVE: To determine whether MRI volumetric measurement of the entorhinal cortex could detect structural damage and lateralize the seizure focus in patients with temporal lobe epilepsy in whom no measurable hippocampal abnormalities were found. BACKGROUND: A reduction in the volume of the entorhinal cortex ipsilateral to the seizure focus in patients with intractable temporal lobe epilepsy and hippocampal atrophy was recently shown. METHODS: MRI volumetric analysis of the entorhinal cortex was performed using a T1-weighted three-dimensional gradient echo sequence in 24 control subjects and 22 patients with temporal lobe epilepsy and normal hippocampal volumes. Thirteen patients underwent surgery, with a mean postoperative follow-up of 36 months. RESULTS: Group analysis (multivariate analysis of variance) showed a reduction in the volume of the entorhinal cortex ipsilateral to the seizure focus in patients with left (p < 0.0001) and right temporal lobe epilepsy (p < 0.0001). Lateralization of the seizure focus could be done in 14 of 22 patients (64%) based on entorhinal cortex volumetry. CONCLUSION: Entorhinal cortex atrophy ipsilateral to the seizure focus supports the presence of structural damage in the mesial temporal lobe in patients with temporal lobe epilepsy and normal hippocampal volumes and emphasizes the participation of the entorhinal cortex in the pathogenesis of this disorder.

Adult↗
PubMed2001

Evidence for reflex activation of experiential complex partial seizures.

Reflex activation of seizures by thoughts or mental images is suggested by patients but has not been objectively demonstrated. The authors present a report of a man with experiential complex partial seizures reliably activated by thinking about his family home. During monitoring, such seizures were repeatedly induced in this way. Seizures were refractory to antiepileptic drugs, but ceased after left temporal resection. Pathologic examination showed cortical dysplasia.

Adult↗
PubMed2001

Lateralizing value of peri-ictal headache: A study of 100 patients with partial epilepsy.

To determine the lateralizing value of peri-ictal headache, the authors conducted a standardized interview of 100 patients with partial epilepsy, 60 with temporal lobe epilepsy (TLE) and 40 with extratemporal epilepsy (ETE). Peri-ictal headache occurred in 47 of 100 (47%) patients. Peri-ictal headache was more likely to be ipsilateral to the seizure onset in TLE (27 of 30 = 90%) than in ETE (two of 17 = 12%; p< 0.001). For both groups, peri-ictal headache usually conformed to the diagnostic criteria for common migraine (18 of 30 = 60% in TLE; 7 of 17 = 41% in ETE).

Adult↗
PubMed2001

Long-term efficacy and safety of piracetam in the treatment of progressive myoclonus epilepsy.

BACKGROUND: Piracetam has been proven to be effective and well tolerated in the treatment of myoclonus in short-term studies. OBJECTIVE: To assess its long-term clinical efficacy, 11 patients with disabling myoclonus due to progressive myoclonus epilepsy were treated with piracetam in an open-label study. METHODS: Neurologic outcome (at the 1st, 6th, 12th, and 18th month of treatment) was assessed by an adjusted sum score of the following 3 indices: motor impairment, functional disability, and global assessment of disability due to myoclonus. Severity of other neurologic symptoms (seizure frequency and severity, dysarthria, and gait ataxia) also was assessed. Treatment with piracetam was initiated at a dose of 3.2 g/d that was gradually increased until stable benefit was noted (maximal dose in the trial was 20 g/d). Concomitant antiepileptic drugs were maintained at their previous dose. RESULTS: Statistically significant improvement in the total rating score was observed after introduction of piracetam at the 1st, 6th, and 12th month of treatment. Severity of other neurologic symptom scores did not improve significantly. Two patients reported drowsiness during the first 2 weeks of treatment. CONCLUSIONS: Piracetam given as add-on therapy seems to be an effective, sustained, and well-tolerated treatment of myoclonus. In patients with progressive myoclonus epilepsy, the efficacy of the drug increased during the first 12 months of treatment and then stabilized.

Adolescent↗
PubMed2001

The role of MRI and nerve root biopsy in the diagnosis of neurosarcoidosis.

OBJECTIVES: Neurological involvement occurs in 5-15% of patients with sarcoidosis and isolated "neurosarcoidosis" occurs in less than 1% of all cases. Classical clinical presentations have been described, such as bilateral facial palsy, but often the disease presents insidiously with varied signs and symptoms. We present a patient who required biopsy of a lumbar nerve root for diagnosis of chronic, progressive neurosarcoidosis and review the literature with an emphasis on diagnosis. METHODS: We have reviewed a patient who presented with signs and symptoms related to infiltration of her meninges and nerve roots by sarcoidosis. All pertinent history and physical information was taken from interviews with the patient and review of her chart. Laboratory, radiographic, and pathological investigations are presented. RESULTS AND CONCLUSIONS: A high index of suspicion is required for the diagnosis of neurosarcoidosis. Gadolinium-enhanced MRI is useful but the findings are often nonspecific, and there should be a low threshold for biopsy whenever the diagnosis is considered.

Biopsy, Needle↗
PubMed2001

Time course of postoperative recovery of N-acetyl-aspartate in temporal lobe epilepsy.

PURPOSE: To assess the time course of increases in N-acetyl-aspartate/creatine (NAA/Cr), which can be measured using proton MR spectroscopic imaging (1H-MRSI), in patients with intractable nonlesional temporal lobe epilepsy (TLE) after successful epilepsy surgery. METHODS: We performed pre- and postoperative 1H-MRSI in 16 seizure-free (SF) patients and 16 not seizure-free (NSF) TLE patients. We calculated a mixed-design analysis of variance (ANOVA) between SF and NSF groups, ipsi- and contralateral to the side of operation, and pre- and postoperative NAA/Cr measurements. We applied nonlinear regression between pre- and postoperative NAA/Cr differences and the time interval between 1H-MRSI scans to fit a negative exponential model to NAA recovery. RESULTS: Mixed-design ANOVA revealed that (a) postoperative NAA/Cr was significantly higher in SF than in NSF patients (p = 0.02) and that (b) in the SF group, postoperative NAA/Cr values were significantly higher than preoperative values (p < 0.05) and returned to the normal range in most patients. According to our nonlinear regression model, in SF patients, there was a 50% increase relative to preoperative NAA/Cr values after 5.8 months, whereas an improvement of 95% was reached after 25 months. CONCLUSIONS: Our results extend preliminary observations of postoperative NAA recovery of SF patients by characterizing the time course of recovery as an exponential function with a half-time of approximately 6 months. The reversal of neuronal metabolic dysfunction remote from the epileptic focus may underlie the clinical observation of improvement of cognitive dysfunction after successful epilepsy surgery.

Adolescent↗