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Lorella Minotti

Publications and source records attributed to Lorella Minotti.

9 recordsLinked to original sources

Reappraisal of the human vestibular cortex by cortical electrical stimulation study.

The cortical areas with vestibular input in humans were assessed by electrical stimulation in 260 patients with partial epilepsy who had undergone stereotactic intracerebral electroencephalogram recordings before surgery. Vestibular symptoms were electrically induced on 44 anatomical sites in 28 patients. The patients experienced illusions of rotation (yaw plane: 18, pitch plane: 6, roll plane: 6), translations (n = 6), or indefinable feelings of body motion (n = 8). Almost all vestibular sites were located in the cortex (41/44): in the temporal (n = 19), parietal (n = 14), frontal (n = 5), occipital (n = 2), and insular (n = 1) lobes. Among these sites, we identified a lateral cortical temporoparietal area we called the temporo-peri-Sylvian vestibular cortex (TPSVC), from which vestibular symptoms, and above all rotatory sensations, were particularly easily elicited (24/41 cortical sites, 58.5%). This area extended above and below the Sylvian fissure, mainly inside Brodmann areas 40, 21, and 22. It included the parietal operculum (9/24 TPSVC sites) which was particularly sensitive for eliciting pitch plane illusions, and the mid and posterior part of the first and second temporal gyri (15/24 TPSVC sites) which preferentially caused yaw plane illusions. We suggest that the TPSVC could be homologous with the monkey's parietoinsular vestibular cortex.

Adolescent↗

Restricted frontomesial epileptogenic focus generating dyskinetic behavior and laughter.

PURPOSE: Substantial data are missing about the anatomic location of frontal regions supporting gelastic seizures. METHODS: We report the results of stereo-electro-encephalographic recordings performed over several distinct functional premotor and executive fields in a patient whose seizures were characterized by dyskinetic behavior and ictal laughter, in the absence of cerebral MRI abnormalities. RESULTS: The epileptogenic zone was circumscribed in the anterior and ventral part of the supplementary motor area and the underlying dorsal cingulate cortex. There were no or little spreading to cortical neighboring areas. The patient is seizure-free (follow-up of 27 months) after a stereotactic electric radiofrequency lesion of the epileptogenic focus. CONCLUSION: The present data suggest that pericingulate premotor areas are involved in the triggering of the motor component of laughter. In this case, the coexistence of paroxysmal dyskinesias during laughter might reflect the involvement of specific compartment(s) of the basal ganglia.

Adult↗

Epilepsy and hypothalamic hamartoma: look at the hand Pallister-Hall syndrome.

We report the case of a 29-year-old patient, who suffered from drug resistant laughing seizures since childhood. The clinical examination was normal, except for sequelae of hand and feet surgery during infancy for post-axial polydactyly. Cerebral MRI showed a hypothalamic hamartoma. The association of complex limb abnormalities with hypothalamic hamartoma lead to the diagnosis of Pallister-Hall syndrome. This syndrome is related to a mutation of gene GLI3, located on chromosome 7p13, and its inheritance is autosomal dominant. In the case of laughing seizures, a cerebral MRI should be performed to look for a hypothalamic hamartoma. The observation of such lesions indicates the necessity of standard radiographies of the hands and feet, to search for associated abnormalities. These findings might help to recognize a Pallister-Hall syndrome, thus allowing genetic counseling.

Adult↗

Antiepileptic effect of high-frequency stimulation of the subthalamic nucleus (corpus luysi) in a case of medically intractable epilepsy caused by focal dysplasia: a 30-month follow-up: technical case report.

OBJECTIVE AND IMPORTANCE: Currently, some forms of epilepsy are resistant to both pharmacological and surgical interventions. As a result, there is a need for new therapeutic strategies. Because the nigral system modulates neuronal excitability in animal models of epilepsy, we considered therapeutic high-frequency stimulation of the subthalamic nucleus (STN). We were encouraged by the known relationship between the STN and the nigral system, as well as by our experience with high-frequency stimulation of the STN in Parkinsonian patients. CLINICAL PRESENTATION: A 5-year-old girl with pharmacologically resistant, inoperable epilepsy caused by focal centroparietal dysplasia underwent implantation with a permanent electrode in the left STN and was chronically stimulated. To date, we have followed up this patient for 30 months postoperatively. TECHNIQUE: High-frequency stimulation of the STN induced a significant voltage-dependent reduction (by 80%) in the number and severity of seizures. In addition, consistent improvement in both motor and cognitive functions was noted as a result of reduced postictal states. The effect was more prominent for seizures occurring in clusters (89% reduction) and during the day (88% reduction) than for those that occurred during sleep (53% reduction). CONCLUSION: This is the first report of epilepsy control using chronic high-frequency stimulation of the STN. Preliminary observations in three other operated patients (at 2, 12, and 18 mo) confirm these data. We think that high-frequency stimulation of the STN may hold significant future potential as a treatment for epilepsy, similar to its established role in the treatment of Parkinson's disease. This finding opens completely new experimental and therapeutic avenues for the treatment of surgically and medically intractable epilepsy.

Brain↗

Anatomy of the temporal pole region.

The temporopolar region is not clearly defined from an anatomical point of view. A line going through the rostral area of the inferior temporal, occipito temporal and superior temporal sulci is considered to represent its posterior limit on the lateral and inferior sides. On the internal side, this posterior limit corresponds to the rhinal sulcus, an anterior and internal extention of the collateral sulcus. From a cyto-architectonic point of view, the temporopolar region is caracterized by a dysgranular paralimbic cortex which ensures the transition between allo- and isocortical areas. The temporal pole is mainly connected with the amygadala, the hippocampus, the superior temporal gyrus, and the occipitobasal cortex, but also with the orbitary gyrus and the insula with which it forms the insulo-orbito-polar-temporo-complex. The temporal pole occupies the most rostral part of the temporal lobe and can only be accurately defined once the anatomy of the temporal lobe as a whole has been outlined. The architectonic configuration of this region as well as its connections with the limbic system, and the superior, orbital and insular temporal cortices make it a discrete temporal structure. Understanding the anatomical and functional organization of the temporal pole enables us to hypothesize about the role played by this structure in the pathogenesis of the forms of epilepsy originating in mesial temporal lobe structures.

Basal Ganglia↗

The role of the temporal pole in the genesis of temporal lobe seizures.

Failure of selective amygdalo-hippocampectomy strongly suggests that the so-called mesio-temporal lobe seizures do not always arise from the sole amygado-hippocampo-parahippocampal complex. Studies in temporal lobe epilepsies have shown that even in the presence of hippocampal sclerosis, the temporo-polar region (TP) is often altered, both histologically, anatomically and functionally. These findings are in accordance with our last ten years experience in stereotactic intracerebral EEG recordings (SEEG), during which we frequently observed the simultaneous involvement of both the amygdala (A), the hippocampus (Hc) and the TP at the onset of temporal lobe seizures. Recently, we have reviewed the SEEG findings of 25 patients with a final diagnosis of temporal lobe epilepsy, in whom both mesial, lateral and polar temporal lobe structures were investigated. The analysis of the most representative seizure in each patient showed that a low voltage fast activity was recorded in the TP either initially or within the first 5 seconds in 13/25 patients (TP group, 52%), while in the remaining 12 cases, ictal discharges started in the Hc and/or amygdala with a later involvement of the TP (AH group, 48%). Preliminary results of a further study conducted in 48 patients have confirmed the high frequency of early TP involvement (2/3 of the cases) in temporal lobe seizures, the clinical characteristics of which did not differ from ictal clinical findings usually described in the mesio-temporal lobe epilepsy syndrome. History of prolonged febrile convulsions and diagnosis of Hc sclerosis were more frequent in the AH group, while early consciousness impairment during seizures and anterior temporal white matter changes on MRI were more frequently observed in TP patients. However a clear-cut distinction between the two groups remains rather difficult in the absence of intracerebral recordings.

Amygdala↗

Deep brain stimulation in epilepsy with particular reference to the subthalamic nucleus.

Alternative methods, for the treatment of medically refractory epileptic patients, who cannot be treated by resective surgery, such as chronic deep brain neurostimulation, are under development. Such methods have been used in the cerebellum, various thalamic nuclei, and in the caudate nucleus. In Grenoble, encouraged by the suppressive effects of pharmacological or electrical inhibition of the STN on different types of seizure in animal models of epilepsy, and by our experience with STN high frequency stimulation (HFS) in patients with movement disorders, we have evaluated the high frequency stimulation of the subthalamic nucleus (STN HFS). STN HFS was performed in five patients suffering from medically intractable seizures and considered unsuitable for resective surgery. A 67% to 80% reduction in seizure frequency was observed in three patients, with a partial symptomatic epilepsy of the central region. An additional patient suffering from severe myoclonic epilepsy (Dravet syndrome) also responded to STN HFS, with a weaker reduction of seizure frequency. The fifth patient who suffered from an autosomal dominant frontal lobe epilepsy with insulo-frontal seizures did not show any improvement. These results suggest that stimulation of STN could be a promising treatment for patients with drug-resistant epilepsy who would not benefit from conventional surgery.

Adolescent↗