PubMed Health⌕ Search

Biomedical subjects

Y Oana

Publications and source records attributed to Y Oana.

14 recordsLinked to original sources
PubMed2000

Predictive variables of interictal psychosis in epilepsy.

OBJECTIVE: To evaluate which variables predict interictal psychosis in epilepsy. METHODS: The authors reviewed the biological backgrounds, clinical characteristics, and EEG findings in 246 patients with epilepsy and interictal psychosis and in 658 control patients with epilepsy and no psychotic history. With a logistic regression approach, the significance of each variable for the development of interictal psychosis was evaluated. RESULTS: There are significant differences in family history of psychosis, age at onset of epilepsy, type of epilepsy, lateralization of epileptiform discharges, and level of intelligence between patients with interictal psychosis and those without it. Subsequent logistic regression analysis with all variables demonstrated that family history of psychosis, age at onset of epilepsy, type of seizures, and level of intelligence significantly correlated with psychosis. CONCLUSIONS: A family history of psychosis, earlier age at onset of epilepsy, complex partial seizures or generalized tonic clonic seizures, and borderline intellectual functioning were the most important predictors for development of interictal psychosis.

Adolescent↗
PubMed2000

Proposal for a new five-axis classification scheme for psychoses of epilepsy.

Based on an overview of the literature and a multicenter study in Japan, we propose a new five-axis classification scheme for psychoses of epilepsy: (1) epilepsy variables, (2) psychopathology variables, (3) ictus/EEG variables, (4) precipitating factors of psychoses, (5) organic background. A total of 128 patients, 63 males and 65 females, with epilepsy and psychoses were recruited from five treatment centers. A wide heterogeneity of psychoses of epilepsy was demonstrated and categorization by a single axis was shown to be inadequate. Cluster analysis revealed four subgroups characterized by their psychopathology, temporal relationship to seizure occurrence, and EEG changes during psychoses. By comparing with the control epileptic group without psychoses, higher rates of mild intelligence disturbance and abnormal findings by brain imaging were proven among the psychotic group. The scheme involves a dimensional representation of individual patients to capture the complexity of their clinical background and to relay clinical information accurately and systematically. It is believed to hold direct therapeutic implications and to contribute to promoting research by enabling accumulation of a large number of patients on a multicenter basis.

Journal Article↗
PubMed1998

Epileptic seizures and pseudoseizures from the viewpoint of the hierarchy of consciousness.

Epileptic seizures and pseudoseizures in temporal lobe epilepsies were studied from the viewpoint of the hierarchy of consciousness. Twenty-two patients with temporal lobe epilepsies (TLE) who showed true amnesia or impairment of consciousness developing from the dreamy state, even though their actions and movement continued, were selected among 160 patients with TLE, nine patients with manifested pseudoseizures, pseudoseizure status, and complex partial seizure status (CPSE) were investigated. Twelve patients in whom impairment of consciousness followed the dreamy state recognized their own existence and maintained some self-directed consciousness. The other 10 patients with amnesia were aware of their goals. Furthermore, pseudostatus ranged from epileptic seizures during pseudoseizure status to pseudoseizures during status epilepticus (SE). In some cases of CPS, awareness and self-directed consciousness were only partially pseudoseizures, disorders of self-directed consciousness are assumed to influence awareness and arousal.

Adult↗
PubMed1994

[Lennox-Gastaut syndrome with series of spasms intermixed with tonic seizures].

A patient with Lennox-Gastaut syndrome developed an unusual feature of periodic spasms (PS), intermixed with tonic seizures. At age 14, she began to have unilateral seizures on awaking, followed by series of spasms Each spasm consisted of rotation of the head to the left and global muscle contraction of the whole body lasting for 0.5-1 second. Ictal EEGs revealed diffuse high voltage slow waves (HVSW), sometimes superimposed upon by diffuse low voltage fast activity, which was related to the increase of muscle activity following the spasms. When the duration of the fast activity on EEG became longer than 2 seconds, the peculiar seizures consisting of combination of asymmetrical spasms and tonic seizures occurred. It is speculated that the fast activity superimposed on HVSW seen in PS represents a transition from PS to tonic seizures.

Adolescent↗
PubMed1993

Ipsilateral and bilateral EEG activity from the hippocampus.

Using scalp and depth electroencephalography (EEG), we examined the relationship between the surface EEG activity and abnormal EEG discharges in the ipsilateral hippocampus in order to study the neuronal connection between the two cerebral regions. Ictal EEG was divided into 4 groups: 1) unitempo-ipsilateral-bifrontal slow waves, 2) unitempo-ipsilateral-bilateral slow waves, 3) bilateral slow waves, and 4) bilateral slow waves with repetitive spikes. Abnormal depth EEG activity in the hippocampus was classified into paroxysmal discharges and recruiting rhythms. Ictally and interictally, repetitive sharp waves or spikes in the unilateral hippocampus were associated with sharp waves or spikes in the ipsilateral temporal region. These findings suggest that the ipsilateral projection of seizure activity originating in the unilateral hippocampus is dependent upon the function of the subiculum.

Adult↗
PubMed1990

[Repetitive rhythmic spikes in epileptic children].

Repetitive rhythmic spikes (RRSs') sometimes appear periodically for 0.2-2.0 seconds at localized in epileptic children. We selected 11 patients (male 6, female 5) with RRSs for this study. Ages were 3-15 years (average 10.7 years). We counted the number of spikes which were recorded on the scalp EEG. The duration of RRSs and the differences of amplitude between large and small spikes on monopolar montages were examined. We also studied the appearance of spikes under different recording conditions; waking and sleep stages, photic stimulation and hyperventilation. Furthermore, we made two dimensional joint-dot plotting for the interval between repetitive spikes. RRSs were classified into two groups. In the first group, joint-dots of RRSs were locally observed between 0.2-0.8 sec. In the second, they were disseminated between 0.2-2.0 sec. In two groups, spikes were mainly observed in the sleep EEG (stage 1). The average number of spikes in the first group was 18.7/min, and that in the second was 25.7/min. The average difference of the amplitude between large and small spikes was 103 microV in the first group, and 88 microV in the second group. The average duration of spikes was 54.2 msec in the first group and 62.4 msec in the second group. From these results, it was assumed that some of spikes in the first group occurred in the surface of the cortex and that some of spikes in the second group were projected from the deep region in the cortex.

Adolescent↗
PubMed1980

Clinical and electroencephalographic study of temporal lobe status.

1. The temporal lobe status appears at a rate of once every 3-5 minutes. 2. The duration of a single temporal lobe seizure is varied, ranging from 10 seconds to 140 seconds. 3. The EEG during seizures is characterized by a generalization of 15-32 Hz recruiting epileptic rhythm which may become 3-7 Hz slow waves later in some cases, 3-7 Hz paroxysmal rhythmic waves. 4. The clinical symptoms are colorful, including apnic seizures, verbal automatism, facial muscle twitching, versive seizure and tonic seizure. The clinical symptoms depend on the size and depth of focus and the scope of propagation of discharge. 5. Generalization cannot be attained merely by the firing of focus that has been formed secondarily. The firing of primary focus is indispensable as the condition for generalization. 6. The focus depends more on the time of the disappearance of discharges than on the site of the primary onset of paroxysm. Particularly important is the length of duration of ictal discharges. 7. The cortico-cortical synapse and the cortico-subcortical pathways were considered the sources of epileptic propagation.

Adult↗