Vol.100 No.1 contentsPRACTICA OTO-RHINO-LARYNGOLOGICA
Vol. 100 No. 1 January 2007
Clinical Study on Unilateral Hearing Loss in Children
Sawako Masuda and Satoko Usui
(National Mie Hospital)
A series of 60 children was studied (aged 0 to 10 years, 32 boys, 28 girls) with severe unilateral sensorineural hearing loss of unknown etiology.
There were two peaks, at 0 and 6 years. In 19 children, hearing loss was identified during a conservative general health checkup for school or preschool children. In 21 children aged 0 years, 16 were suspected of hearing loss by newborn hearing screening.
Temporal bone computed tomography scans were examined in 51 patients. Sixteen ears (31.4％) with hearing loss had inner ear and/or internal auditory canal abnormalities. In one patient, the anomaly was the presence of a bony wall dividing the internal auditory canal into two separate compartments associated with severe inner ear hypoplasia. Two patients had a common cavity. In one of these patients, the anomaly was revealed because of severe bacterial meningitis, and another was detected by newborn hearing screening. Six patients had a narrow internal auditory canal, 4 had a narrow internal auditory canal and hypoplastic cochlea, and 1 had a narrow internal auditory canal and cystic vestibule, and lateral semicircular canal dysplasia. Two patients had a cystic vestibule and lateral semicircular canal dysplasia.
One case showed fluctuation of the hearing level in the contralateral ear with normal hearing during the observation period at an average of 20 months.
The number of children whose unilateral hearing loss is detected early by newborn hearing screening has enormously increased. Strategies for follow-up, early intervention, and support for families are necessary for young children with unilateral hearing impairment.
Key words :unilateral hearing loss, child, newborn hearing screening, temporal bone computed
tomography scan, anomaly