Biomedical subjects

F Gilliam

Publications and source records attributed to F Gilliam.

52 records · Page 3Linked to original sources

PubMed1997

Supplementary sensorimotor area epilepsy. Seizure localization, cortical propagation and subcortical activation pathways using ictal SPECT.

We studied clinical signs, EEGs and ictal cerebral blood flow by single-photon emission computed tomography (SPECT) in eight patients with intractable supplementary sensorimotor area (SSMA) seizures. SPECT scans were performed after injection of the regional cerebral blood flow tracer [99mTc]HMPAO (hexametylpropylene amine oxime) early in the ictal phase (2-5 s after seizure onset). Ictal SPECT demonstrated unilateral predominance of hyper-perfusion of the SSMA in all patients, concordant with either lateralizing clinical signs, lateralization of ictal scalp EEG or with the site of ictal onset of seizures, obtained from intracranial electrodes. Two distinctive cortical blood-flow propagation patterns were identified in SSMA seizures. The type I pattern consisted of primary involvement of the ipsilateral SSMA and dorsal premotor and motor cortex. The type II pattern consisted of bilateral but asymmetric mesial frontal propagation. Ictal contraversive head and eye movements were associated with a type I propagation pattern (P < 0.03). Activation of subcortical structures led to variable hyper-perfusion of the basal ganglia and thalamus. Contralateral cerebellar hyperperfusion was observed in all cases. We conclude that ictal SPECT is a useful method for seizure localization in patients with SSMA epilepsy. The observed heterogeneity of clinical features in SSMA epilepsy correlates with propagation to, and activation of, specific cortical structures, and is consistent with known anatomical interconnections between the SSMA, ipsilateral cortical and transcallosal cortical structures.

Adolescent↗

PubMed1997

Association of combined MRI, interictal EEG, and ictal EEG results with outcome and pathology after temporal lobectomy.

PURPOSE: Magnetic resonance imaging, interictal scalp EEG, and ictal scalp EEG each have been shown to localize the primary epileptic region in most patients with mesial-basal temporal lobe epilepsy (MBTLE), but the association of surgical outcome and pathology with each combination of these test results is not known. METHODS: We reviewed the MRI, interictal scalp EEG, and ictal scalp EEG results of 90 consecutive patients with MBTLE. Twelve patients were excluded from the analysis because inconclusive bitemporal intracranial EEG results precluded anterior temporal lobectomy (ATL); none had concordant MRI and interictal scalp EEG results. We compared all combinations of presurgical MRI, interictal EEG, and ictal EEG results to seizure outcome and tissue pathology in the 78 patients who underwent an ATL. RESULTS: Forty-eight (61%) patients had concordant lateralized MRI and interictal EEG temporal lobe abnormalities, with no discordant ictal EEG results; 77% of these patients were seizure-free after ATL. Concordance of MRI and interictal EEG abnormalities correlated with seizure cessation (p < 0.05), compared to all combinations with discordant or nonlateralizing MRI and interictal EEG results. Mesial temporal sclerosis (MTS) was confirmed pathologically in about 80% of both groups (p = 0.5). Outcome in patients with concordant MRI and ictal EEG with nonlateralizing interictal EEG was significantly worse than combinations with concordant MRI and interictal EEG (p < 0.02). CONCLUSIONS: Compared to other combinations of test results, concordance of MRI and interictal EEG is most closely associated with surgical outcome in MBTLE. However, most selected patients have pathologic confirmation of MTS regardless of test results or outcome. This information may be useful for planning the presurgical evaluation of patients with medically intractable MBTLE.

Adolescent↗

PubMed1997

Occipital lobe developmental malformations and epilepsy: clinical spectrum, treatment, and outcome.

PURPOSE: Cortical developmental malformations (CDM) are increasingly recognized in association with epilepsy. We describe 10 patients (age range 14-35 years) with symptomatic occipital lobe epilepsy and CDM. METHODS: Neurologic, neuroophthalmologic and electrophysiologic studies were performed. Patients had MRI, SPECT, and in some cases intracranial EEG investigators. RESULTS: Mean age of seizure onset was 8 years. We noted strong correlations between the presence of visual auras, the scalp EEG pattern, and the subtype of underlying pathology. Magnetic resonance imaging (MRI) showed CDM in all patients, with polymicrogyria and focal dysplasia being the most frequent malformations. Despite the presence of occipital lobe structural malformations in all patients, visual field deficits were present in only 2. Those who underwent cortical resections were seizure-free or showed major improvement at a mean follow-up of 3.5 years. CONCLUSIONS: Intracranial stimulation studies and the low frequency of pre- and postoperative deficits suggest that some degree of cortical visual reorganization may occur in patients with occipital lobe malformations. Occipital lobe CDM should be sought as a cause of symptomatic occipital lobe epilepsy even though they may become symptomatic after childhood.

Adolescent↗

PubMed1997

Patient-validated content of epilepsy-specific quality-of-life measurement.

PURPOSE: To study the effects of epilepsy from the patients' perspective and assist determination of content validity of health-related quality-of-life (HRQOL) measures. METHODS: We asked 81 consecutive patients with moderately severe epilepsy to list in order of importance their concerns of living with recurrent seizures. To minimize investigator bias, patients completed the procedure in a private setting without staff involvement. RESULTS: Twenty-four distinct domains were generated by the patients. Concerns about driving (64%), independence (54%), employment (51%), social embarrassment (36%), medication dependence (33%), mood/stress (32%), and safety (31%) each were listed by > 30% of patients. Driving was listed as the most important concern by 28% of patients, followed by employment (21%), independence (9%), safety (6%), antiepileptic-drug side effects (5%), seizure unpredictability (5%), and seizure aversion (5%). CONCLUSIONS: The effect of epilepsy on HRQOL is not vague or obscure from the patients' perspective but is defined by a limited number of domains. Independence is an important concern that may not be evaluated adequately by currently available HRQOL instruments.

Activities of Daily Living↗

PubMed1997

Proton spectroscopic imaging at 4.1 tesla in patients with malformations of cortical development and epilepsy.

We used proton magnetic resonance spectroscopic imaging (MRSI) at 4.1 tesla in patients with malformations of cortical development (MCDs) and epilepsy. We compared the spectroscopic results with normative data using 2 SDs (95% confidence) above normal values for detection of significant abnormalities for creatine-N-acetylated compounds (Cr/NA) ratio and choline-N-acetylated compounds (Cho/NA). The results were correlated with clinical, EEG, and histologic findings. Patients with focal cortical dysplasia showed significant metabolic abnormalities in correspondence with the structural lesions, whereas patients with heterotopia and polymicrogyria demonstrated no subcortical MRSI abnormalities. Significant correlations were found between the metabolic abnormalities and the frequency of seizures but not with the degree of interictal EEG discharges. Quantitative neuronal and glial cell counts revealed no statistically significant correlation between cell loss and the abnormal metabolic ratios in those who underwent surgery. These preliminary findings suggest that MRSI-based metabolic abnormalities in patients with MCDs are variable and are likely to be associated with complex cellular mechanisms involving the regulation of NA, total Cr content, and Cho.

Acetylation↗

PubMed1997

Epilepsy surgery outcome: comprehensive assessment in children.

The effect of extratemporal and temporal lobe cortical resection on children with intractable epilepsy is not well understood. We evaluated a comprehensive array of outcome variables in 33 consecutive children who received epilepsy surgery at 12 years of age or younger. Twenty-two (67%) children were seizure-free, three (9%) had a greater than 90% reduction in seizures, and four had no improvement. Antiepileptic drugs (AEDs) were not required in 10 (30%) children and were reduced in number in another 10. Six (29%) of 21 tested children had an improvement of greater than 10 points in Verbal or Performance IQ after surgery, while one (4%) had a decrease greater than 10 points in Verbal IQ. One mild hemiparesis and one inferior quadrantanopsia occurred; both were anticipated. We used the Child Health Questionnaire (CHQ), a valid and reliable instrument for children, to assess health-related quality of life (HRQOL). Six of 12 subscale scores of the CHQ were significantly lower in the surgical group compared with 410 age-matched control subjects. Parents were satisfied with surgical results in 28 (85%) cases. Pathologic tissue diagnosis and site of resection were not associated significantly with any outcome measure. We conclude that surgery eliminates seizures and reduces AED requirements in most children with intractable epilepsy selected by currently available methods. Further investigation is needed to establish the nature and significance of inferior scores in the surgical group in the HRQOL domains of physical function, general health, and self-esteem.

Adolescent↗

PubMed1997

Multimodality MRI in mesial temporal sclerosis: relative sensitivity and specificity.

Our objectives were to determine the relative sensitivity and specificity of different MRI sequences and analysis techniques for the detection of mesial temporal sclerosis (MTS). Mesial temporal sclerosis is the most common pathologic finding in patients undergoing temporal lobe epilepsy surgery. Magnetic resonance imaging is the most reliable preoperative imaging technique for the detection of MTS. We analyzed the abnormalities in preoperative MRIs of 44 consecutive patients who had undergone temporal lobectomy and who had pathologic confirmation of MTS. Techniques included inversion recovery (IR); T1-weighted, volume-acquired images; hippocampal T2 relaxometry (HT2); volumetric assessment; and visual analysis. Sensitivity was 86% with IR, 90% with T1-weighted qualitative visual analysis, and 97% with quantitative volumetry. Pathologic prolongation of HT2 (> 2 SD of normal) was present in 79%. Analysis of variance showed statistically significant differences in sensitivity between HT2, volumetric measurements (p < 0.01), and qualitative visual atrophy (p < 0.05). Concordance between all MRI modalities was 68%. Inversion recovery and qualitative analysis lateralized the side of surgery in 93%. The combination of IR and T1-weighted images correctly identify MTS in most patients. Hippocampal volumetry provided localization in an additional small number of patients.

Adolescent↗

PubMed1997

Congenital porencephaly and hippocampal sclerosis. Clinical features and epileptic spectrum.

We studied clinical features and seizure localization in 14 patients with porencephaly and intractable seizures. Perinatal complications were present in nine patients, childhood febrile convulsions in two, congenital hemiparesis in 12, and intellectual impairment in seven. Ten patients had psychoparetic complex partial seizures (CPS), three had sensorimotor simple partial seizures, and one had generalized tonic-clonic seizures. Surface EEG showed temporal onset in nine patients (one bitemporal) and extratemporal onset in four. MRI showed porencephaly in the distribution of the middle cerebral artery in eight patients, posterior cerebral in three, internal carotid in one, and multiple vessels in two. MR-based volumetry revealed hippocampal formation atrophy in 13 patients (eight unilateral and five bilateral) and amygdalar atrophy in 10 patients (nine unilateral and one bilateral). Hippocampal formation atrophy was concordant with CPS semiology in 10 patients (71%) and with EEG temporal localization in nine patients. Two patients had pathologic confirmation of mesial temporal sclerosis and were seizure free after temporal lobectomy. We conclude that mesial temporal sclerosis often coexists with porencephaly and is the likely seizure focus in the presence of concordant electroclinical data. This recognition implies that effective surgical intervention can be offered to certain patients with porencephaly-related seizure disorders. The dual pathology and association with perinatal cerebral vascular occlusion suggest a common ischemic pathogenesis.

Adolescent↗

PubMed1996

Diagnostic testing of seizure disorders.

Although a thorough history and physical examination remain the basis for the evaluation of patients with a possible seizure disorder, electroencephalography (EEG) is a necessary extension of the neurologic examination. Most patients also require a magnetic resonance imaging (MRI) scan to identify a potentially epileptogenic lesion. This article reviews the technical considerations, common findings, and potential pitfalls related to the use of EEG and MRI. Adjunctive test such as ambulatory EEG, video/EEG, positron emission tomography, single photon emission computed tomography, and serum evaluation also are discussed for use in specific circumstances.

Adolescent↗

PubMed1996

Qualitative MRI segmentation in mesial temporal sclerosis: clinical correlations.

Magnetic resonance imaging (MRI) is reliable and sensitive in the detection of mesial temporal atrophy in patients with temporal lobe epilepsy. We investigated the MRI patterns of atrophy in 47 patients with histologically confirmed hippocampal sclerosis and correlated the imaging findings to the clinical features and surgical outcome. One hundred percent of patients had hippocampal body atrophy, 70% had hippocampal tail atrophy, 23% had amygdala atrophy, and 10% had focal hippocampal body atrophy without other segmental involvement. Correlative analysis of the segmented MRI findings with other clinical variables, including a previous history of childhood febrile convulsions, showed no significant associations except for younger age of seizure onset associated with hippocampal tail atrophy (p <0.03). No associations between surgical outcome and the patterns of mesial temporal atrophy were detected. Our results demonstrate that variable patterns of atrophy exist in mesial temporal atrophy, but invariably atrophy involves the hippocampal body segment. Segmental MRI analysis in mesial temporal atrophy provides added useful diagnostic information.

Adolescent↗

PubMed1996

Parental assessment of functional outcome after corpus callosotomy.

PURPOSE: We wished to evaluate functional outcome and parental satisfaction after corpus callosotomy. METHODS: We studied a cohort of parents of 17 patients who had received an anterior corpus callosotomy > 7 months earlier (mean 26 months) for severe, intractable seizures. Parental satisfaction with the overall surgical results was the primary outcome measure. In addition, the parents assessed behavior changes that had been emphasized preoperatively as important aspects of their children's function, including alertness and responsiveness, falls and injuries, and special care needs. Degree of seizure reduction and extent of corpus callosum were also measured. RESULTS: The parents of 15 (88%) patients reported satisfaction with the surgical outcome. All parents who expressed satisfaction would recommend callosotomy to another family in a similar situation. The behavior change most closely associated with satisfaction was improved alertness and responsiveness (p < 0.03). Although 9 patients experienced > 80% reduction in targeted seizures, satisfaction was not reported at a greater rate as compared with the 6 patients with 50-80% reduction. CONCLUSIONS: Most parents report satisfaction with the outcome of their child's corpus callosotomy, but are influenced by improvement in aspects of function and behavior in addition to seizure reduction.

Adolescent↗

PubMed1995

Discordant occurrence of cerebral unilateral heterotopia and epilepsy in monozygotic twins.

Cerebral developmental malformations are increasingly recognized as a cause of epilepsy. Magnetic resonance imaging (MRI) has advanced our understanding of these disorders and their relation to epilepsy. We report the occurrence of discordant unilateral heterotopia and epilepsy in monozygotic twins. The affected individual developed intractable focal seizures at age 16 years. Mild cognitive difficulties had been present in early life. Evaluation showed right hemisphere EEG epileptogenic abnormalities, and the MRI scan showed massive right hemisphere heterotopia. EEG and MRI examinations in the patient's twin brother were normal. These findings suggest that the development of some developmental brain malformations and epilepsy is strongly influenced by nongenetic factors such as an environmental insult.

Adult↗

PubMed1995

Ictal amaurosis: MRI, EEG, and clinical features.

We studied seven consecutive patients who experienced amaurosis as a prominent feature of their seizures. The mean age of seizure onset was 4 years. Six patients had MRI abnormalities including ischemic, traumatic, and space-occupying lesions, with five limited to the parietal-occipital region. Six patients had unilateral, posterior interictal spike and slow wave complexes. Four patients experienced severe postictal headache and nausea. Absence of a family history of seizures distinguished the patients with MRI lesions from previously presented series of benign occipital lobe epilepsy. We conclude that the constellation of ictal amaurosis, occipital paroxysms, and postictal migrainous symptoms does not necessarily signify a benign, nonlesional epilepsy; MRI is recommended for such patients without a family history of similar seizures.

Adolescent↗

PubMed1993

Hemi-field pattern reversal visual evoked potentials in migraine.

A study of hemi-field pattern reversal visual evoked potentials recorded in the interictal phase was carried out in 44 patients (22 with migraine with aura, 22 without aura) in order to determine whether migraine patients with or without aura and with headaches with strong unilateral predominance, either left or right, exhibit abnormalities after hemi-field stimulation. No differences of P100 latency were found between them and a group of 20 normal individuals, between patients suffering from migraine with aura and migraine without aura and between the affected and the non-affected side of the head. Only in a subgroup of 14 patients with headaches constantly lateralized to a single side, either left or right, was the P100 latency significantly shorter on the affected side (p < 0.001, t-test) compared with the contralateral non-affected side. The results indicate that in both types of migraine there is a common underlying pathogenetic mechanism and the affected retrochiasmatic optic radiation has an increased response to sensory input modulation.

Adolescent↗

PubMed1991

Postictal language assessment and lateralization of complex partial seizures.

We performed a prospective study of ictal and postictal language function after 105 temporal lobe complex partial seizures in 26 patients. Seizure localization was verified by a greater than 90% reduction in seizure frequency after temporal lobectomy. At the time of the seizure, the patient was asked to read a test phrase aloud until it was read correctly and clearly. In all 62 seizures originating from the left temporal lobe, the patient took more than 68 seconds to read the test phrase correctly (mean, 321.9 seconds); in 42 of 43 seizures from the right temporal lobe, the patient read the test phrase in less than 54 seconds (mean, 19.7 seconds). Postictal paraphasias occurred in 46 of 62 seizures from the left temporal lobe (11 of 14 patients). In this study, quantifying the time delay in reading a test phrase lateralized seizure onset in all 26 patients tested, proving significantly more accurate than any other single noninvasive presurgical test.

Adolescent↗

PubMedDate not supplied

EEG spike detection with a Kohonen feature map.

Artificial neural networks are widely used for pattern recognition tasks. For spike detection in electroencephalography (EEG), feedforward networks trained by the backpropagation algorithm are preferred by most authors. Opposed to this, we examined the off-line spike detection abilities of a Kohonen feature map (KFM), which is different from feedforward networks in certain aspects. The EEG data for the training set were obtained from patients with intractable partial epilepsies of mesiotemporal (n=2) or extratemporal (n=2) origin. For each patient the training set for the KFM included the same patterns of background activity and artifacts as well as the typical individual spike patterns. Three different-sized networks were examined (15 x 15 cells, 25 x 25 cells, and 60 x 60 cells in the Kohonen layer). To investigate the quality of spike detection the results obtained with the KFM were compared with the findings of two board-certified electroencephalographers. Application of a threshold based on the partial invariance of spike recognition against translation of the EEG provided an average sensitivity and selectivity of 80.2% at crossover threshold (71%-86%) depending on the networksize and noise. Multichannel EEG processing in real time will be available soon. In conclusion, pattern-based automated spike detection with a KFM is a promising approach in clinical epileptology and seems to be at least as accurate as other more-established methods of spike detection.

Adult↗