[Ictal nystagmus: acquired nystagmus of infrequent cause in pediatrics]. / Nistagmo ictal: causa infrecuente de nistagmo adquirido en pediatría.

Ictal nystagmus is a rare phenomenon secondary to an epileptic seizure, usually in the temporo- occipital region. For its characterization, we must rely on clinical history, examination, and ideally observation of the episodes. OBJECTIVES: To describe a case of this unusual entity and highlight the characteristics that should increase diagnostic suspicion in order to avoid treatment delay. CLINICAL CASE: An 8-year-old schoolboy, with no relevant history, consulted due to 5-6 episodes a day in the last year of conjugate horizontal eye movements with rapid jerks and associated slight miosis, lasting 5-10 seconds, with doubtful disconnection from the environment or consciousness impairment in some of the episodes, with no other accompanying signs or symptoms. Neurological examination between episodes was normal. He was evaluated by ophthalmology and otolaryngology, which ruled out pathology in these areas. Video-electroencephalogram showed electro-clinical correlations, with epileptiform activity in the left temporal and occipital region, which subsequently generalized during episodes. Brain MRI showed no pathological findings. After initiation of carbamazepine treatment, the patient had a good evolution, without recurrence of the episodes at 2 years of follow-up. CONCLUSIONS: When faced with a case of acquired nystagmus, epileptic etiology should be included in the differential diagnosis, especially if the frequency of episodes is high, of short duration, and associated with consciousness impairment. The diagnosis is based on a video-electroencephalogram with electro-clinical correlations and a good response to treatment with antiepileptic drugs is expected.

Correlación del umbral de potencial evocado auditivo de tronco cerebral con el umbral de potencial evocado auditivo de estado estable en pacientes hipoacúsicos / Correlation of the threshold of auditory brainstem response with the auditory steady state response in hearing loss patients

RESUMEN Introducción: El avance de los dispositivos de ayuda auditiva han ocasionado a su vez el desarrollo de las técnicas electrofisiológicas destinadas al diagnóstico de la sordera. Objetivo: Comparar los umbrales del potencial evocado auditivo de tronco cerebral (PEATC) y del potencial evocado auditivo de estado estable (PEAee) en niños con hipoacusia. Material y método: Estudio observacional descriptivo de una serie de casos de pacientes de 0 a 6 años de edad con hipoacusia, diagnosticada mediante PEATC y PEAee. Se compara el umbral de la onda V en el PEATC y la media del valor registrado en 2 y 4 kHz en el PEAee mediante la correlación de Spearman y se utiliza el índice Kappa para conocer la concordancia entre las mismas. Resultados: Se diagnosticaron 89 oídos con hipoacusia, 23 con hipoacusia profunda. Se obtiene un valor de rho de Spearman de 0,64 (p <0,001). El índice de Kappa obtenido es del 0,59 con un IC al 95% entre 0,52 y 0,66 (p <0,001). La diferencia media de umbrales entre el PEAee y el PEATC es de −2,42 dB con una desviación estándar de 13,11 dB. Conclusión: Se obtiene un grado de relación y acuerdo moderado entre las pruebas, influido sobre todo por los pacientes con hipoacusia profunda. Los umbrales del PEAee son mayores que los del PEATC.

ABSTRACT Introduction: The advancement of hearing aid devices has led to the development of electrophysiological techniques for the diagnosis of hearing loss. Aim: To compare the thresholds of auditory brainstem response (ABR) with the auditory steady state response (ASSR) in hearing loss children. Material and method: A descriptive observational study of cases from 0 to 6 years of age with hearing loss, diagnosed by ABR and ASSR was performed. The Spearman correlation test is used to compare the threshold obtained for the V wave in the ABR and the average value recorded in 2 and 4 kHz in the ASSR. To know the concordance between the two tests, the Kappa index is used. Results: 89 ears were diagnosed with hearing loss, 23 with profound hearing loss. The Spearman's rho value is 0.64 (p <0.001). The Kappa index obtained is 0.59 with a 95% CI between 0.52 and 0.66 (p <0.001). The mean difference thresholds between the ASSR and the ABR is −2.42 dB with a standard deviation of 13.11 dB. Conclusion: A moderate relationship and agreement between the tests is obtained, influence especially in patients with profound hearing loss. The thresholds of ASSR are higher than those of ABR.