PubMed Health⌕ Search

Biomedical subjects

V A Sironi

Publications and source records attributed to V A Sironi.

At least 19 recordsLinked to original sources
PubMed1982

Differences between the concentrations of antiepileptic drugs in normal and pathological human brain.

The concentrations of antiepileptic drugs in histologically normal and pathological brain tissues were investigated in 6 patients submitted to surgery. No significant difference for phenobarbital and phenytoin was found between normal and scar tissue, whereas there was a trend to concentration in tumour tissue (meningioma and glioma) of phenobarbital, phenytoin and carbamazepine. Alteration in the vascular supply and pathological changes at cellular and subcellular levels could be responsible for the differences in the distribution of the drugs. The possible clinical relevance of the preferential concentration of the drugs in tumour tissue is discussed.

Adolescent↗
PubMed1980

Stereo-EEG and surgery in partial epilepsy with temporo-parieto-occipital foci.

Six cases of partial epilepsy operated on for lesions at the temporo-parieto-occipital junction are presented. Three cases had signs of enlargement of one lateral ventricle at the temporo-parieto-occipital carrefour, three had a lateral homonymous hemianopsia and all showed lateralizing interictal EEG abnormalities. The manifold features of the seizures could not be related to the involvement of one or more definite cortical areas. Since clinical, radiological, scalp EEG investigations provided no sufficient data to map the epileptogenic lesion to be excised, stereo-EEG studies with chronic depth electrodes were performed. Besides permitting the exact delimitation of the epileptogenic lesion, depth EEG gave the clue for interpreting physiopathological mechanisms underlying the electroclinical seizures in each case.

Adolescent↗
PubMed1980

Late results of stereotactic radiofrequency lesions in epilepsy.

Thirty-five patients with partial complex seizures and two patients with generalized epilepsy were treated by stereotactic radiofrequency lesions. Follow-up from 2 to 13 years was available in 30 patients. The stereotactic targets in patients with partial complex seizures were: a) Amygdala; b) Ammon's horns; c) parahippocampal gyrus; d) Fornix. Depending on scalp EEG and depth electrode studies, each patient had one or more target coagulated, unilaterally or bilaterally. In the 2 cases of generalized epilepsy, bilateral Forel field lesions were performed. Late surgical results are discussed in relation to the depth EEG studies and the number and site of stereotactic lesions.

Adolescent↗
PubMed1980

Antiepileptic drug distribution in cerebral cortex, ammon's horn, and amygdala in man.

Significant correlations in the concentrations of phenobarbital, phenytoin, and carbamazepine in the brain, plasma, and cerebrospinal fluid were found in 12 surgically treated epileptic patients. These findings confirm the clinical reliability of monitoring anticonvulsant drug plasma levels as part of the routine management of epilepsy. Phenobarbital, phenytoin, and carbamazepine are uniformly distributed in the gray and white matter in different brain areas (except for a higher concentration of phenobarbital in the rhinencephalic structures in comparison with the corresponding temporal neocortex) and in normal and scar tissue. In these 12 patients, all of whom were medically resistant, molar cortex concentration of phenobarbital and phenytoin was at "therapeutic" levels or even higher. These data suggest that in therapy-resistant patients, despite cerebral drug concentrations of the same therapeutic level as, or higher than, those present in medically controlled patients, anticonvulsant drugs are pharmacologically ineffective.

Adolescent↗
PubMed1979

Interictal acute psychoses in temporal lobe epilepsy during withdrawal of anticonvulsant therapy.

Acute interictal psychotic attacks during withdrawal of medication are described in two patients with temporal lobe epilepsy submitted to depth EEG study with a view to surgical treatment. The patients were on chronic treatment with clonazepam associated in one with phenobarbitone and in the other with phenobarbitone plus carbamazepine. Our observations suggest that the acute withdrawal of clonazepam, the plasma levels of which were monitored may play a part in producing psychotic attacks characterised by dysphoric manifestations, irritability, aggressiveness, anxiety, and hallucinations. These symptoms could be interpreted as a withdrawal syndrome.

Adult↗
PubMedDate not supplied

[Deep cerebral electrical activity during the hypnotic state in man: neurologic considerations in hypnosis].

To the authors' knowledge hypnosis has never been induced in epileptic patients during depth EEG study. This neurosurgical diagnostic procedure (that has been routinely used in medically resistant epileptic patients for the preoperative exact delimitation of the epileptogenic lesion) offers a unique opportunity of obtaining fundamental information on the possible neurophysiological mechanisms implied in human hypnosis. Observations were carried out on 3 consecutive patients affected by medically resistant partial seizures with elementary and/or complex symptomatology. A chronic deep electrode study explored rhinencephalic structures as well as specific target areas of the cerebral cortex. Background electrical activity during the hypnotic state showed a significant decrease of slow waves and an increase of alpha and beta rhythms, with constant increase of amplitude, as compared with the nonhypnotic state. Focal interictal abnormalities were drammatically reduced by hypnotic trance. Moreover, depth EEG study during sleep in one patient indicated that the EEG patterns during hypnosis and sleep are basically different, confirming that there is no convincing evidence of physiological similarities between the 2 states.

Adult↗
PubMedDate not supplied

Indications of anticonvulsant plasma levels monitoring in medical and surgical treatment of epilepsy.

The results of long-term (19-21 months) intensive anticonvulsant plasma levels monitoring in two patients with partial complex epilepsy resistant to therapy are reported. In the first case the qualitative and quantitative therapeutic adjustment based on the monitoring data caused the disappearance of the seizures. In the second case, in which a right mid-temporal calcification (abscess) was demonstrated by CT-scan, the attacks were not controlled by different drugs. The patient became seizure-free after a right temporal lobectomy. The importance of long-term anticonvulsant plasma levels monitoring in partial complex epilepsies unresponsive to pharmacological therapy is discussed in detail in view of possible surgical treatment.

Adolescent↗
PubMedDate not supplied

Anal protrusion as a complication of ventriculo-peritoneal shunt. Case report and review of the literature.

A case is reported in which the Raimondi peritoneal catheter of a ventriculoperitoneal shunt spontaneously protruded from the anus in an infant. This complication has been previously reported; both pathogenesis and treatment may still represent a problem. From the review of the pertinent literature pathogenesis is mostly related to bowel perforation due to local infective adhesions. Treatment does not imply major abdominal surgery, if after avulsion of the extruded catheter and exteriorization of the shunt no peritoneal signs are present.

Anal Canal↗
PubMedDate not supplied

[Interruption of antiepileptic therapy in seizure-free patients following surgery to remove the epileptogenic lesion].

This paper presents a series of 20 epileptic patients operated on at our Institute, with a clinical, EEG and drug plasma level follow-up, for periods from 48 to 60 months. Following surgery a group of 12 patients were seizure-free in a 3 year period of follow-up, and anticonvulsant medication was gradually withdrawn. While in 8 of these patients drug interruption uneventful, in 4 cases drug withdrawal caused the seizure to reappear. These 4 patients became seizure-free again, following a reintroduction of pharmacological therapy, which appeared to be effective also at low doses. Another group of 8 patients continued to have seizure also after surgery. Following quantitative and qualitative adjustments of their anticonvulsant medication, 5 patients became again seizure-free, while 3 continued to have seizures. Our experience suggests that in patients in whom the epileptogenic lesions have been surgically removed, anticonvulsant therapy can be safely withdrawn and removed after a seizure-free period of 3 years. Reappearance of seizures after drug withdrawal has a good prognosis, since a simple readjustment of medical therapy is usually effective in preventing further seizures to occur.

Adolescent↗