RESUMEN
Auditory event-related potentials (AERP) were elicited in 68 epileptic patients and 30 age-matched controls. Epileptic patients had significantly prolonged N2 and P300 (P3) latencies compared with controls. Seven patients were above the range of 3 standard deviations from the control mean values. Amongst epileptics, patients with temporal lobe epilepsy had significantly prolonged P3 latencies compared to patients with idiopathic generalized epilepsy. Patients with abnormal EEGs had significantly prolonged P3 latencies compared to those with normal EEGs. Patients on anticonvulsant monotherapy had shorter P3 latencies, compared to patients taking a combination of two or more anticonvulsants. Patients on shorter duration of treatment had less prolonged P3 latencies compared to those on longer anticonvulsant treatment.
Asunto(s)
Anticonvulsivantes/uso terapéutico , Trastornos del Conocimiento/fisiopatología , Electroencefalografía/efectos de los fármacos , Epilepsias Parciales/fisiopatología , Epilepsia Generalizada/fisiopatología , Potenciales Evocados Auditivos/fisiología , Tiempo de Reacción/fisiología , Adolescente , Adulto , Corteza Cerebral/efectos de los fármacos , Corteza Cerebral/fisiopatología , Epilepsias Parciales/tratamiento farmacológico , Epilepsia del Lóbulo Frontal/tratamiento farmacológico , Epilepsia del Lóbulo Frontal/fisiopatología , Epilepsia Generalizada/tratamiento farmacológico , Epilepsia del Lóbulo Temporal/tratamiento farmacológico , Epilepsia del Lóbulo Temporal/fisiopatología , Potenciales Evocados Auditivos/efectos de los fármacos , Femenino , Humanos , Masculino , Persona de Mediana Edad , Tiempo de Reacción/efectos de los fármacosRESUMEN
Auditory Event-Related Potentials (AERP) were elicited in 25 beta-thalassemic patients, three days before and three days after a blood transfusion. The amplitude, latency and topographic distribution of P300 (P3) as well as N1, P2, N2 components were measured for the two assessment times. No significant differences in either amplitude, latency or topography were observed between the two situations, but thalassemic patients had significantly prolonged P3 latencies comparing to controls though none of them exceeded 3 standard deviations of the control mean values. Regarding P3 topography, 10 out of 25 patients showed a right centroparietal distribution area. It is concluded that information processing, as far as it is reflected in AERP components is impaired in thalassemic patients and blood transfusion have no significant influence in cognitive functions.
Asunto(s)
Encéfalo/fisiopatología , Cognición/fisiología , Potenciales Evocados Auditivos/fisiología , Talasemia beta/fisiopatología , Adolescente , Adulto , Mapeo Encefálico , Electroencefalografía , Femenino , Humanos , Masculino , Tiempo de Reacción/fisiologíaRESUMEN
Auditory event-related potentials (AERP) were elicited in 47 patients with relapsing-remitting (RR) multiple sclerosis (MS) and 24 age-matched controls. MS patients had significantly prolonged N2 and P3 latencies as well as low P3 amplitude compared with controls. Seven of them exceeded 3 standard deviations from the control mean values. The observed N2 and P3 alterations are associated with the patients' disability status as it is defined by the Kurtzke expanded disability status scale (EDSS), but are not related to the duration of the disease. A possible cognitive decline as reflected in the observed AERP components alterations in MS patients is subsequently discussed.
Asunto(s)
Nivel de Alerta/fisiología , Atención/fisiología , Daño Encefálico Crónico/fisiopatología , Electroencefalografía/instrumentación , Esclerosis Múltiple/fisiopatología , Procesamiento de Señales Asistido por Computador/instrumentación , Adulto , Daño Encefálico Crónico/diagnóstico , Mapeo Encefálico/instrumentación , Corteza Cerebral/fisiopatología , Potenciales Evocados Auditivos/fisiología , Femenino , Humanos , Masculino , Esclerosis Múltiple/diagnóstico , Discriminación de la Altura Tonal/fisiología , Tiempo de Reacción/fisiologíaRESUMEN
This report presents data on visual evoked potentials (VEPs) and brainstem auditory evoked potentials (BAEPs), as well as neurologic, ophthalmologic and otologic assessments performed on 120 patients with beta-thalassemia major undergoing long-term DFO treatment. A total of 32 patients showed abnormal VEPs and 14 abnormal BAEPs; seven had both VEP and BAEP abnormalities; 12 had sensorineural hearing loss (SNHL); 18 had conductive hearing loss, while 14 showed a combination of SNHL and conductive hearing loss. After DFO administration was modified (taking in consideration the serum ferritin levels) patients with abnormal findings were retested. The values of 15 patients of 23 who underwent VEP examinations had been normalized. Eleven of 15 who repeated the BAEP test had also gained normal values. The audiogram had not returned to normal in any patient with SNHL. In a second repetition of the examinations, no change was observed. It is concluded that in a great percentage of thalassemics at least one of the above examinations shows abnormal values. These abnormalities are mostly reversible, and probably reflect a dysfunction of the visual or auditory system, due either to DFO neurotoxicity or to iron overload or both.