Auditory evoked potentials in children at neonatal risk for hypoacusis / Potenciales provocados auditivos en niños con riesgo neonatal de hipoacusia

Brainstem auditory evoked potentials provide a simple, noninvasive method of evaluating hearing function and have been widely used for early detection of hypoacusis in children. Between April 1992 and May 1994, a stydy was done of 400 Mexican children who presented at least one neonatal risk factor for hearing impairment. The average age of the children studied was 6.6 months and their average gestational age at birth was 35.1 weeks. Just over half of the children had been treated with amikacin. The study found 1427 risk factors (about 3.5 per child), the most common ones being exposure to ototoxic substances, hyperbilirubinemia, and birthweight <1500 g. In 27 por cent of the children, peripheral auditory changes were found, and 13 por cent did not respond to auditory stimuli. Low birthweight and young gestational age at birth, high serum concentration of bilirubin, sepsis, subependymal or intraventricular hemorrhage, mechanical ventilation, and exposure to ototoxic substances were significantly associated with the presence of severe or profound hypoacusis

Los potenciales provocados auditivos del tallo cerebral son un método sencillo y no invasor de evaluación de la función auditiva, que se utiliza ampliamente en niños para detectar tempranamente hipoacusia. Entre abril de 1992 y mayo de 1994, se estudiaron 400 niños mexicanos que presentaban, al menos, un factor de riesgo neonatal de hipoacusia. La media de la edad de los niños estudiados fue 6,6 meses y la media de la edad gestacional al nacer, 35,1 semanas. El 51% de ellos fueron tratados con amikacina. Se registraron 1 427 factores de riesgo (3,5 por niño), entre los que predominaron la exposición a ototóxicos, la hiperbilirrubinemia y el peso al nacer <1 500 g. En 27% se encontraron alteraciones auditivas de tipo periférico y en 13%, ausencia de respuesta a estímulos auditivos. El bajo peso y la menor edad gestacional al nacer, la concentración máxima de bilirrubina en el suero, la presencia de sepsis, la hemorragia subependimaria o intraventricular, la ventilación mecánica y la exposición a ototóxicos se asociaron significativamente con la presencia de hipoacusia grave o profunda

Large vestibular aqueduct syndrome

Large vestibular aqueduct syndrome [LVAS] is a radiologically diagnosed syndrome. Children with delayed speech and hearing loss without any middle ear disorder should arouse the suspicion of inner ear congenital anomaly. A computerized tomography [CT] scan is essential to rule out the possibility of LVAS in these children. Until recently no satisfactory treatment was available either to improve the hearing or to prevent further deterioration of hearing loss in this condition. The hearing loss in these two sisters began in childhood and progressed slowly. One of them also had a history of sudden diminution of hearing at one stage. Neither of them has had any vestibular symptoms. They were fitted with hearing aids and both the sisters are doing well in their education in normal school. Another two cases

Waardenburg syndrome in Iran

Waardenburg Syndrome is characterized by white forelock, heterochromic iris, wide nasal root, canthus dystopia, congenital hearing loss and has a dominant inheritance with variable degree of penetrance. The appearance of clinical signs in this syndrome varies considerably among different individuals. Three cases of Waardenburg syndrome are presented here. First case was a soldier with binaural total deafness and white forelock and blue eyes. His sister was also deaf. Second case was a child, nine years old, with profound hearing loss; his hearing was unserviceable. He had heterechromic eyes but lack forelock. There were instances of congenital hearing loss among his paternal relatives. Third case was a young man with different colours of the eyes, confluent eyebrows white discolouration of hairs and binaural hearing loss