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Biomedical subjects

O Devinsky

Publications and source records attributed to O Devinsky.

At least 127 records · Page 7Linked to original sources
PubMed1991

Herpes zoster myelitis.

We studied the clinical (10 patients) and pathological (9 patients) findings in 13 patients with herpes zoster myelitis, all of whom had systemic illnesses associated with immunosuppression. The median interval between the onset of the herpes zoster rash and myelopathic symptoms was 12 days, and the subsequent median interval to maximal deficit was 10.5 days. Presenting neurological symptoms were characteristically ipsilateral to the rash, with motor dysfunction predominating, followed by a spinothalamic and, less often, posterior column sensory deficit. Pathological involvement was most severe in the dorsal root entry zone and posterior horn of the spinal cord segment corresponding to the involved dermatome. There was variable spread both horizontally and vertically in the spinal cord. Direct varicella-zoster virus (VZV) infection of neuroectodermal cells, particularly oligodendrocytes, was demonstrated by immunostaining viral antigens (8 cases), and by the presence of Cowdry type A intranuclear inclusions (7 cases) and often was associated with focal demyelination (6 cases). In 4 patients a VZV vasculitis was associated with leptomeningitis and haemorrhagic necrosis (spinal cord in 1; brainstem or cerebellum in 3). The protracted evolution in many cases and the pathologically documented direct viral infection of the spinal cord provide a rational basis for the use of antiviral therapy in preventing or attenuating the evolving myelopathy.

Adult↗
PubMed1991

Phenytoin intoxication.

We studied the clinical features of 85 cases of phenytoin toxicity in 76 patients treated at a general hospital. Serum levels of phenytoin on admission ranged from 30.3 to 95.0 micrograms/mL (median, 46.5). Iatrogenic causes of intoxication were common and included increased daily dosage and intravenous loading in the emergency room for single seizures in patients with subtherapeutic serum phenytoin levels. The most frequent neurologic findings were nystagmus (95%), ataxia (88%), lethargy (22%), and seizures (19%). Outcome was usually good, but three patients had serious complications.

Adult↗
PubMed1991

Clozapine-related seizures.

Clozapine is an atypical antipsychotic drug with minimal extrapyramidal toxicity recently approved by the Food and Drug Administration for hard-to-treat schizophrenic patients. We reviewed information on 1,418 patients treated with clozapine in the United States between 1972 and 1988. Forty-one of 1,418 (2.8%) patients had generalized tonic-clonic seizures during treatment with clozapine. Life-table analysis predicts a cumulative 10% risk of seizures after 3.8 years of treatment. Clozapine-related seizures appear to be dose-related. High-dose therapy (greater than or equal to 600 mg/day) was associated with a greater risk of seizures (4.4%) than medium (300 to 600 mg/day; 2.7%) or low doses (less than 300 mg/day; 1.0%). Also, rapid upward titration may increase seizure risk. Thirty-one of 41 patients were successfully continued on clozapine despite seizure occurrence, either with reduction of dose or addition of an antiepileptic medication. Recognition and treatment of clozapine-related seizures will become increasingly important as its use grows in the 1990s.

Adult↗
PubMed1990

Relation of EEG alpha background to cognitive function, brain atrophy, and cerebral metabolism in Down's syndrome. Age-specific changes.

We studied 19 young adults (19 to 37 years old) and 9 older patients (42 to 66 years old) with Down's syndrome (DS) and a control group of 13 healthy adults (22 to 38 years old) to investigate the relation of electroencephalographic (EEG) alpha background to cognitive function and cerebral metabolism. Four of the older patients with DS had a history of mental deterioration, disorientation, and memory loss and were demented. Patients and control subjects had EEGs, psychometric testing, quantitative computed tomography, and positron emission tomography with fludeoxyglucose F 18. A "blinded" reader classified the EEGs into two groups--those with normal alpha background or those with abnormal background. All the control subjects, the 13 young adult patients with DS, and the 5 older patients with DS had normal EEG backgrounds. In comparison with the age-matched patients with DS with normal alpha background, older patients with DS with decreased alpha background had dementia, fewer visuospatial skills, decreased attention span, larger third ventricles, and a global decrease in cerebral glucose utilization with parietal hypometabolism. In the young patients with DS, the EEG background did not correlate with psychometric or positron emission tomographic findings, but the third ventricles were significantly larger in those with abnormal EEG background. The young patients with DS, with or without normal EEG background, had positron emission tomographic findings similar to those of the control subjects. The mechanism underlying the abnormal EEG background may be the neuropathologic changes of Alzheimer's disease in older patients with DS and may be cerebral immaturity in younger patients with DS.

Adult↗
PubMed1990

Depression, anxiety, and temporal lobe epilepsy. Laterality of focus and symptoms.

The association between anxiety, depression, and lateralization of an epileptogenic focus was explored in 18 adult patients with a left temporal lobe focus, 21 with a right focus, 20 with bilateral temporal foci, and 16 individuals with absence seizures. No significant difference in the level of anxiety was found among the groups. However, patients with left-sided temporal lobe epilepsy scored significantly higher than other groups on self-ratings for depression. This could not be accounted for by factors such as duration of epilepsy, employment status, education, age at seizure onset, or medication status. The left temporal lobe epilepsy group had a nonsignificantly larger number of males and left-handed subjects. The possible interactions between gender, handedness, seizure focus, and vulnerability to depression are described.

Adult↗
PubMed1990

General assay for phosphoproteins in cerebrospinal fluid: a candidate marker for paraneoplastic cerebellar degeneration.

The components of protein phosphorylation systems (protein kinases, protein phosphatases, and their phosphoprotein substrates) are highly enriched in neuronal cells compared with other cell types. We exploited this relative neuronal enrichment of protein phosphorylation system components to develop a general assay technique for putative protein kinase substrates (phosphoproteins) in human cerebrospinal fluid. Using this cerebrospinal fluid phosphoprotein assay, we have detected a putative protein kinase C substrate protein of apparent Mr 60 kd in 6 of 14 patients with paraneoplastic cerebellar degeneration but not in any of 55 patients with a variety of other neurological diseases. Phosphoproteins in cerebrospinal fluid may provide novel and unique markers for the diagnosis or staging of neuronal diseases as well as offer potential insights into the biochemical characterization of affected neuronal populations.

Adult↗
PubMed1989

Benzodiazepine withdrawal delirium with catatonic features. Occurrence in patients with partial seizure disorders.

We report the cases of 3 patients with medically intractable seizures in whom withdrawal of treatment with a long-acting benzodiazepine (clorazepate dipotassium, 2 patients; clonazepam, 1 patient) was followed by delirium with catatoniclike features. While an increase in seizure frequency occurred during withdrawal and prior to the onset of behavioral changes, electroencephalograms did not show epileptiform activity during the delirium. We compared these 3 patients with 10 others with intractable seizures in whom antiepileptic therapy was withdrawn without subsequent behavior changes. High-dose benzodiazepine therapy and a history of viral encephalitis may be risk factors for withdrawal delirium.

Adult↗
PubMed1989

Autoscopic phenomena with seizures.

We report the cases of 10 patients with seizures and autoscopic phenomena, which include seeing one's double and out-of-body experiences, and review 33 additional cases of autoscopic seizures from the literature. Autoscopic phenomena may be symptoms of simple partial, complex partial, or generalized tonoclonic seizures. Autoscopic seizures may be more common than is recognized; we found a 6.3% incidence in the patients we interviewed. The temporal lobe was involved in 18 (86%) of the 21 patients in whom the seizure focus could be identified. There was no clear lateralization of lesions in patients with ictal autoscopy. The response of autoscopic episodes to treatment usually paralleled that of the underlying seizure disorder. Autoscopic phenomena are likely to be discovered only on specific questioning of patients with epilepsy and may be an important, distressing feature of a chronic seizure disorder.

Adult↗
PubMed1989

Electroencephalographic studies of simple partial seizures with subdural electrode recordings.

We used subdural electrodes to study the EEG features of simple partial seizures in 7 patients. We detected epileptiform discharges in 61 of 68 subdurally recorded simple partial seizures compared with 6 of 55 simple partial seizures recorded with scalp electrodes (p less than 0.0001). The onset of 36 nonmotor simple partial seizures was detected only by the medial and basal temporal subdural electrodes, and the onset of 25 simple partial seizures with motor manifestations was recorded by subdural electrodes only from the lateral cortex of the posterior frontal lobe. There was a close correspondence between the area first involved in the epileptiform discharge during simple partial seizures and the area first involved during complex partial and secondary generalized tonic-clonic seizures. Subdural electrodes may be effective in localizing the onset and spread of simple partial seizures, including those that arise from the medial temporal lobe.

Adult↗
PubMed1989

Dissociative states and epilepsy.

Since symptoms of chronic dissociative disorders such as multiple personality disorder (MPD) may be shared by patients with seizure disorders, we investigated the possible relationship between dissociative states and epilepsy. We monitored 6 MPD patients with intensive video-EEG recordings to determine whether epileptic phenomena have any correlation to the dissociative symptoms experienced by these patients. Previously, physicians had diagnosed epilepsy in all 6 patients; however, none proved to have epilepsy. In addition, we studied dissociative symptoms in 71 epileptic patients with the aid of a standardized questionnaire, the Dissociative Experiences Scale, and compared them with age-matched controls. While the group median score of cases with complex partial seizures was higher than that of normal controls, it was significantly lower than that of the psychiatric patients with MPD. Partial seizure patients with dominant hemisphere foci had higher depersonalization subscale scores than those with nondominant foci. Our data suggest that epilepsy is not a primary pathophysiologic mechanism for developing dissociative symptoms.

Adult↗
PubMed1989

Phenytoin withdrawal and seizure frequency.

We withdrew phenytoin from 17 inpatients maintained on combination therapy with carbamazepine for complex partial seizures and analyzed seizure occurrence in relation to plasma levels and time from initiation of withdrawal. The ratio of maximum to mean weekly seizure frequency did not vary with initial level or rate of withdrawal. The week with most frequent seizures began a median of 10 days after phenytoin levels became undetectable, and mean daily seizure frequency was higher at undetectable than at falling levels for the entire 2- to 10-week study period. Four patients had a total of 6 clusters of generalized tonic-clonic seizures; only 2 occurred while levels were falling and the other 4 at 3, 9, 28, and 42 days after reaching undetectable levels. Our data argue against the occurrence of withdrawal seizures in these patients and suggest that worsening of seizures following phenytoin discontinuation more likely reflects loss of therapeutic drug effect than a true abstinence phenomenon.

Adult↗
PubMed1989

Fear episodes due to limbic seizures with normal ictal scalp EEG: a subdural electrographic study.

The authors present the case of a 13-year-old girl with episodes characterized by either staring with preserved consciousness or fear in whom functional illness was suspected. Video-EEG telemetry revealed no changes during 30 of 32 attacks. Subdural electrode recordings revealed epileptiform discharges in 30 of 37 episodes. The discharge was always localized to the electrodes recording from the inferomedial temporal region, with electrodes over the lateral convexity of the same temporal lobe showing no background changes. Although the detailed pathophysiology of panic attacks remains to be clarified, the authors point out that their case and other epileptic case studies are consistent with the possibility that excessive neuronal activity in medial temporal lobe structures is a necessary element of the underlying mechanism.

Adolescent↗
PubMed1988

Confusional states following posterior cerebral artery infarction.

Four patients with left-sided posterior cerebral artery infarction developed acute confusional states. Fifteen additional patients with confusion following unilateral posterior cerebral artery infarction were identified from a review of the literature; in 14 the lesion was left sided. Destruction or disconnection of dominant hemisphere neocortex from limbic structures, resulting in impairment of focal attention, loss of linguistically organized memory, and/or disruption of temporal sequencing may be responsible for this syndrome.

Acute Disease↗
PubMed1988

J. Russell Reynolds and the study of interictal symptoms in epilepsy.

Sir John Russell Reynolds (1828-1896) was a prominent English neurologist who was among the first to carefully study interictal behavior in patients with epilepsy. He challenged the prevailing dogma that severe mental illness was nearly always concomitant of epilepsy. Studying the cognitive and emotional functions of 62 patients with essential (idiopathic) epilepsy, he found that 39% of the patients were normal, 32% had only mild impairment of recent memory, and 29% had moderate to severe psychopathologic findings. His study of interictal behavior in epilepsy is one of the earliest attempts to avoid selection bias and represents an important contribution to the study of this problem.

England↗
PubMed1988

Clinical and neuropathological findings in systemic lupus erythematosus: the role of vasculitis, heart emboli, and thrombotic thrombocytopenic purpura.

We reviewed the medical records and autopsy reports of 50 patients with systemic lupus erythematosus to determine the clinical and neuropathological features of this disease. Neuropsychiatric disturbances were found in the majority (74%) of the patients, occurring as psychiatric illness only (5 patients), neurological disorders only (15 patients), and both together (17 patients). Central nervous system (CNS) lesions were present in half the patients; embolic brain infarcts (10 patients) and CNS infections (8 patients) were the most common. Cardiac sources of emboli were Libman-Sacks endocarditis (5 patients), chronic valvulitis (2 patients), and left side of heart mural thrombus (2 patients). There was no evidence of active CNS vasculitis. Clinical features of thrombotic thrombocytopenic purpura (TTP) developed during the terminal illness in 14 patients, 7 of whom also had pathological evidence of TTP. Correlation between neuropsychiatric disorders and brain lesions could be made in approximately half the patients. This study indicates that cardiac emboli from Libman-Sacks endocarditis and TTP are common pathogenetic factors of CNS disease in systemic lupus erythematosus, whereas CNS vasculitis is rare.

Adolescent↗
PubMed1988

Cerebrospinal fluid pleocytosis following simple, complex partial, and generalized tonic-clonic seizures.

We observed postictal pleocytosis in 7 of 62 cerebrospinal fluid specimens obtained from 27 patients with epilepsy. Each patient had a known seizure disorder; none had any other cause for the pleocytosis. The maximum number of leukocytes was 12/mm3; the maximum number of erythrocytes was 190/mm3. Postictal pleocytosis was more common in samples obtained within 12 hours of the last seizure. Although previous studies have emphasized that pleocytosis is more common after repetitive generalized tonic-clonic seizures, we found increased leukocyte counts in cerebrospinal fluid after single simple, complex partial, or generalized tonic-clonic seizures.

Adolescent↗
PubMed1988

Clinical and electroencephalographic features of simple partial seizures.

The clinical and electroencephalographic features of 87 simple partial seizures in 14 patients were studied with video-EEG telemetry. The patients were able to respond to verbal stimuli during all seizures and, later, could clearly recall ictal events. To determine whether the EEG changes in simple partial seizures could be reliably observed, a reader blindly reviewed four EEGs of equal duration for each seizure. These EEGs consisted of one ictal and three nonictal recordings obtained at predetermined times before the seizure. There were 27 motor seizures (mean duration, 86 seconds; range, 2 to 250 seconds), all involving clonic movements of the head and/or upper extremities; 8 (30%) of these had a sensory component (pain in 6, paresthesia in 2). An EEG change, usually localized spikes or sharp waves over the contralateral or both rolandic regions, was identifiable in nine (33%) of the motor seizures. The 60 nonmotor seizures (mean duration, 63 seconds; range, 8 to 375 seconds) involved a variety of symptoms, including somatosensory/special sensory (3 seizures), autonomic (26 seizures), cognitive (1 seizure), affective (14 seizures), and mixed, or more than one category of nonmotor symptoms (16 seizures). In only nine (15%) of the nonmotor seizures was there an ictal EEG change, usually localized spikes or paroxysmal theta activity over the temporal region. Overall, among the 87 simple partial seizures, only 18 (21%) revealed ictal EEG changes. Thus, a normal EEG is common during simple partial seizures and does not exclude the diagnosis.

Adolescent↗