7 research outputs found
Evaluación de los sistemas sensoriales en pacientes con epilepsia del lóbulo temporal mesial fármaco–resistente sometidos a tratamiento quirúrgico
No full textBy its anatomical relationship with temporal lobe, auditory and visual pathways are susceptible to anatomical or functional changes after surgical resection of temporal lobe used as a therapeutic option in patients with mesial temporal lobe epilepsy drug-resistant (ELTm-FR). We studied a sample of 28 patients with ELTm-FR operated at the International Center of Neurological Restoration between 2002 and 2012, in order to evaluate possible changes of auditory and visual sensory systems secundary to the anterior temporal lobectomy guided by electrocorticography. It was noted the existence of functional abnormalities in auditory and visual sensory systems before surgical intervention in comparison with a group of healthy subjects. After resection were detected changes in the functioning of the auditory pathway through the use of auditory evoked potentials, probably mediated by an indirect effect and long-term removal of specific structures such as the amygdala and the middle temporal pole structures. In the visual pathway resection of epileptogenic zone prompted visual field defects that were evidenced by the techniques of visual evoked potentials with stimulation by quadrants in combination with perimetry, and which corresponded to the magnitude of the neocortical tissue removed. The visual pathway lesion could be substantiated through the tractography of optic radiation and the state of its connectivity. These results should be considered for the evaluation of patients with ELTm-FR who undergo surgical treatment.Por su relación anatómica con el lóbulo temporal, las vías auditiva y visual son susceptibles de sufrir cambios anatómicos y/o funcionales luego de la resección quirúrgica del lóbulo temporal utilizada como opción terapéutica en pacientes con epilepsia del lóbulo temporal mesial fármaco–resistente (ELTm–FR). Estudiamos una muestra de 28 pacientes con ELTm–FR intervenidos quirúrgicamente en el Centro Internacional de Restauración Neurológica entre los años 2002 y 2012, con el objetivo de evaluar los posibles cambios de los sistemas sensoriales auditivo y visual secundarios a la lobectomía temporal anterior guiada por electrocorticografía. Se constató la existencia de alteraciones funcionales en los sistemas sensoriales auditivo y visual antes de la intervención quirúrgica en comparación con un grupo de sujetos sanos. Luego de la resección se detectaron cambios en el funcionamiento de la vía auditiva mediante el empleo de los potenciales evocados auditivos, probablemente mediados por un efecto indirecto y a largo plazo de la remoción de estructuras específicas como la amígdala y el polo temporal medio. En la vía visual la resección de la zona epileptógena provocó defectos del campo visual que fueron evidenciados por las técnicas de potenciales evocados visuales con estimulación por cuadrantes en combinación con la perimetría, y que se correspondieron con la magnitud del tejido neocortical removido. La lesión de la vía visual pudo ser corroborada mediante la tractografía de la radiación óptica y el estado de su conectividad. Estos resultados deben ser considerados para la evaluación de pacientes con ELTm–FR que sean sometidos a tratamiento quirúrgico
Relation of Structural and Functional Changes in Auditory and Visual Pathways after Temporal Lobe Epilepsy Surgery
No full textAuditory and visual pathways may be affected as a consequence of temporal lobe epilepsy surgery because of their anatomical relationships with this structure. The purpose of this paper is to correlate the results of the auditory and visual evoked responses with the parameters of tractography of the visual pathway, and with the state of connectivity between respective thalamic nuclei and primary cortices in both systems after the surgical resection of the epileptogenic zone in drug-resistant epileptic patients. Tractography of visual pathway and anatomical connectivity of auditory and visual thalamus-cortical radiations were evaluated in a sample of eight patients. In general, there was a positive relationship of middle latency response (MLR) latency and length of resection, while a negative correlation was found between MLR latency and the anatomical connection strength and anatomical connection probability of the auditory radiations. In the visual pathway, significant differences between sides were found with respect to the number and length of tracts, which was lower in the operated one. Anatomical connectivity variables and perimetry (visual field defect index) were particularly correlated with the latency of P100 wave which was obtained by quadrant stimulation. These results demonstrate an indirect functional modification of the auditory pathway and a direct traumatic lesion of the visual pathway after anterior temporal lobectomy in patients with drug resistant epilepsy
