Biomedical subjects

A Cukiert

Publications and source records attributed to A Cukiert.

13 recordsLinked to original sources

PubMed1992

Brain SPECT in the pre-surgical evaluation of epileptic patients. Preliminary results.

Pre-surgical evaluation of epileptic patients consists of neurological examination, intensive electroencephalographic (EEG) monitoring and anatomical studies (CT and MRI). Functional methods such as PET and SPECT imaging are now used more frequently. We have studied pre-operatively 15 adult epileptic patients (8 female, 7 male) using a rotational scintillation camera interfaced to a dedicated computer. The tomographic images were obtained 15 minutes after intravenous injection of 99mTc-HMPAO. All had MRI scanning and intensive EEG monitoring which generally included seizure recording. Five patients had progressive lesions (3 meningiomas, 2 astrocytomas). In 10 patients, neuroradiological studies did not show the presence of progressive lesions (2 normal scans and 8 cases with inactive lesions). Two patients with meningioma showed hypoperfusion at the lesion site while the third patient had a marked hyperperfusion which might correlate with the clinical diagnosis of epilepsia partialis continua. In the astrocytoma patients SPECT scans showed hypoperfusion at the lesion site. Data obtained from the 10 patients without progressive CNS lesions showed: (a) in 4, SPECT findings correlated well with the anatomical findings; (b) in 5 instances, SPECT was able to disclose additional functional deficits; (c) in one case, there was no SPECT correlate of a discrete anatomical lesion. In 5 of these cases with no progressive lesions (n = 10) SPECT findings were useful as a complementary tool in determining the clinical or surgical management of these patients. Despite the small number and heterogenicity of the present sample, SPECT seems to be an useful tool as part of the clinical workup of epileptic patients who are candidates for epilepsy surgery.

Adult↗

PubMed1992

Traumatic callosotomy.

In a 33 years-old epileptic woman with a traumatic impact to the vertex, clinical and radiological studies (skull X-R, CT and MRI) disclosed an extensive callosal section under the topography of the falx, associated to fronto-basal contusions. There was a significant improvement in the epileptic syndrome. No interhemispheric disconnection syndrome could be determined, which is compatible with the posterior regions of the corpus callosum having been spared. This is, to the best of our knowledge, the most extensive callosal injury documented by MRI to date.

Accidental Falls↗

PubMed1991

Knowledge about epilepsy among teachers and epileptic patients.

223 epileptics patients and their families and 136 teachers from public and private schools were submitted to similar questionnaires related to inheritance, transmission, cure, complication rates, care during seizures, need for information on the disease, habits, comparison with other diseases and to the educational and social performance of epileptics. Cure and complication rates accounted for the main differences between those populations. Epileptics could recognize a bigger number of complications but still expected to be cured from the disease. The majority of teachers and patients have never been informed about epilepsy and this finding was related to the big number of equivocal answers obtained from them. Put together, the data showed that social and educational performance of epileptic patients could be disturbed by medical and social parameters. Some of them could be improved by an educational program towards these aspects of epilepsy.

Adult↗

PubMed1991

Eating epilepsy.

Eating epilepsy is a rare type of reflex epilepsy. A 24 years-old male with eating reflex complex partial seizures was submitted to clinical, neurological, neuroradiological and EEG studies. Neurologic and CT examinations were normal. EEG recordings including video-EEG monitoring during meals disclosed focal abnormalities related to both temporal lobes prevailing at the left side and secondary bilateral synchrony mainly in more anterior regions. Ictal findings were similar to the interictal secondary bilateral synchrony except for its longer duration. PB, VPA and DPH monotherapies were ineffective. High dose CBZ monotherapy yielded good but incomplete seizure control. Since a big number of precipitants could be involved, no specific physiopathological basis could be established.

Adult↗

PubMed1991

Secondary bilateral synchrony associated to a parasagittal tumor. Case report.

A 32 years old woman who had postural limbic and primarily generalized tonic-clonic seizures since the age of 11 presented to us with a CT image strongly suggestive of a mesial meningioma near the right cingulum. Her ictal EEG pattern was characterized by regular 1.5-2.0 Hz sharp and slow wave complexes. A right craniotomy was performed under general anesthesia and intraoperative electroencephalographic and electrocorticographic recordings were obtained by means of scalp steel electrodes and modified cerebellar stimulation electrodes, respectively. These recordings demonstrated that surface spikes were often independent from the electrocorticographically recorded ones. Before tumor excision, electrical stimulation of the peritumoral mesial cortex resulted in an increase in the epileptic activity. The stimulation of the cavity left after tumor excision led to a prolonged electrographic seizure and neurophysiological procedures were stopped. Post-operatively, the patient has remained seizure free for 6 months and her EEG was normal. The pre-, intra- and postoperative findings in this case suggest that the gliotic peritumoral mesial cortex was at least involved in the epileptogenic process.

Adult↗

PubMed1990

Mental deterioration in Lafora's disease.

Lafora's disease is included among the progressive myoclonic epilepsies. Despite the fact that dementia is a constant finding in this disease only a few papers have studied the timing of mental deterioration. We have performed wide neuropsychological testing in two cases early diagnosed as Lafora disease. The initial neuropsychological testing was carried out by the time there were no complaints of mental deterioration in both cases. In the first case consecutive neuropsychological testing demonstrated the rapidly progressive dementia. All neuropsychological testings in these cases showed severe impairment of right parietal lobe functions. Higher cortical functions related to language and intellectual processes were best preserved in both cases. The functions related to constructional praxis, memory and abstract concepts and processes were severely impaired. Our data suggest that mental deterioration is an early manifestation in Lafora disease, even by the time normal social life is not yet disturbed. Dominant hemisphere cognitive functions have been less impaired than the non-dominant ones. How a diffuse illness such as Lafora disease can cause such an asymmetrical higher cortical function deficit is not yet clear.

Adolescent↗

PubMed1989

Effects of corpus callosum stimulation on the morphology and frequency of epileptic bursts in the feline topical penicillin generalized model.

Twelve cats were stimulated at the rostrum of the corpus callosum while full epileptic activity was recorded after topical application of penicillin on the cortex bilaterally. Electrocorticography was performed bilaterally. In 6 animals the electrode position was checked by evoked potentials. Stimulation parameters ranged from 0.5 to 1,000 Hz, from 2 to 10 mA, and from 0.5 to 5.0 ms. No significant modification was found in frequency, synchrony, and morphology of the epileptic bursts and spikes, suggesting that callosal stimulation, at least using this model, is ineffective in reducing epileptic activity.

Animals↗

PubMed1989

Unilateral topical cortical application of penicillin: electrographic aspects. A new complement to an old model.

In 7 cats 800 IU of penicillin were applied diffusely over one hemisphere on the exposed neocortex. After 40 min all animals showed bilateral and synchronous burst discharges with a higher amplitude at the hemisphere where the penicillin had been applied. These data fill a gap in the literature concerning feline generalized penicillin epilepsy, in which penicillin is applied bilaterally on the exposed neocortex.

Administration, Topical↗

PubMed1989

An evoked potential mapping of transcallosal projections in the cat.

In ten adult cats anesthetized with ketamine hydrochloride the neocortex was exposed and rectangular pulses (1 msec, 0.5 Hz and variable intensity) were applied to discrete points of one side and transcallosal evoked potentials were recorded from the other. The stimulation and recording positions were determined on a cartesian map of most of the exposable neocortical areas and the potentials were analysed as to their components, voltage and latency. Passive spread and electrotonic potentials and the effects of increasing frequency were also analysed. The results showed large transcallosal potentials in some areas and an increase of potentials in the caudorostral direction, attaining the highest values in anteromedial areas of the suprasylvian gyrus. Confirming anatomical studies, a few silent spots were found in the motor and somesthetic cortex and in restricted posterior regions of the visual cortex, where small or zero voltages occurred. While causing weak contralateral potentials, stimulation of some posterior sites provoked high voltage potentials in anterior regions of the side being stimulated and in the corresponding area of the opposite site. These posterior sites are poorly interconnected by the corpus callosum. The L-shaped indirect connection described in this work may be involved in some types of epilepsy and may explain the effectiveness of partial callosotomy in their treatment.

Animals↗

PubMed1989

Non-epileptic myoclonus and mitochondrial encephalomyopathy.

Two brothers presented to us with a progressive myoclonic syndrome with slight cerebellar symptoms. Neurological examination disclosed moderate cerebellar signs and pale optic discs; asymmetric, asynchronous and arrhythmic myoclonus, an arrthesthesic deficit and no muscular weakness. EEG background activity was moderately slow with no irritative discharges. CT was normal in both cases. Intermittent photic stimulation increased the frequency of the myoclonic jerks, which became bilateral and synchronous, progressing to a generalized tonic-clonic seizure. EPs and MRI in one case were normal. Anticonvulsant drugs were ineffective. The diagnosis of mitochondrial encephalomyopathy was based on the finding, in muscle specimens, of thickened basement membranes with myofibrillary degeneration and increased number of mitochondria peripherally distributed and with a dense granular matrix and some vacuoles. The clinical and EEG data suggest a subcortical origin for this type of myoclonic syndrome.

Adult↗

PubMed1989

Electrophysiological evidence for an L-shaped interhemispheric connection in the cat.

Transcallosal potentials evoked by electrical stimulation with rectangular pulses of 1 ms, 5 c/s and variable intensity were recorded from the cortical surface in cats anesthetized with ketamine hydrochloride. Sites of stimulation and recording were selected by means of a cartesian map of most of the neocortex. In addition to the well known transcallosal projection pattern it was found that stimulation of a restricted posterior area evokes low voltage potentials over the contralateral symmetric area while high voltage potentials are recorded from a few sites located at the ipsilateral anterior cortex and from the area symmetric as to the latter. This L-shaped transcallosal connection may be involved in complex cortical processes and is compatible with effective results of partial anterior callosotomies in patients with multifocal epilepsy and frontal bisynchronism.

Animals↗

PubMed1986

[Epidemiological aspects of epilepsy in São Paulo: a prevalence study].

Several studies on epidemiology of epilepsy were carried out in different parts of the world. However, the majority of their data was collected from hospitals, clinics, individual physicians and or small communities. Although these studies have contributed to our knowledge as to the risk factors of epilepsy, some of them have prevented us from further generalization, since the prevalence rates of the phenomena were not known for the entire population where from they were derived. Latin America has remained without epidemiological data, specially prevalence rates, for many years. A house-to-house survey was programmed by the Brazilian League of Epilepsy in the urban area of S. Paulo City the third largest cosmopolitan city in the world: 13 million inhabitants in 1980. A significant sample of 2011 houses was chosen by statistical means. A total of 7603 interviews were performed by 50 senior medical students and nurses, and 388 persons were considered suspect and further referred to our University Hospital for other studies; 348 of these were examined, and in 91 the diagnosis of epilepsy was confirmed, thus producing a prevalence rate 11.9 per 1000.

Brazil↗

PubMed1983

A pretectal projection upon the accessory optic nucleus in the pigeon: an anatomical and electrophysiological study.

Neurons of the nucleus lentiformis mesencephali, the avian homologue of the optic tract nucleus, were retrogradely filled with horseradish peroxidase after injections of the enzyme into the accessory optic nucleus in pigeons. The projection appeared exclusively ipsilaterally, and was confirmed by unitary and evoked potential recordings. Together with previous reports in both birds and mammals, the present study contributes information linking the accessory optic system to the pretectal nucleus of the optic tract and thence to horizontal optomotor mechanisms.

Afferent Pathways↗