P300 potentials evoked by tones and spoken words were recorded from a 20-year-old man with a House-3M single-channel cochlear implant. Three months after cochlear implantation, there was a slight appearance of P300 response to both pure-tone stimuli and spoken-word stimuli; 6 months later, clearly identifiable P300 response to both pure-tone stimuli and spoken-word stimuli were obtained. These results are consistent with an encoding improvement for re-establishment of information processing after auditory rehabilitation.

Mutations in the GJB2 gene (connexin 26) are the most common cause of nonsyndromic autosomal recessive sensorineural hearing loss. Genetic testing of GJB2 may offer opportunities to predict the features of hearing loss and prognostication of speech-language development in children with hearing loss. The present study assessed the clinical features of hearing and some aspects of language development in congenital deafness due either to GJB2 mutations or to other factors in Japanese patients who had been habilitated with hearing aids. Thirty-five unrelated subjects with nonsyndromic, congenital, bilateral sensorineural hearing loss were enrolled in the study. Among them, 16 had biallelic GJB2 mutations related to hearing loss and 17 lacked such mutations. As has been reported in populations of European ancestry, the present Japanese subjects with GJB2 mutations had a relatively high incidence of the flat pattern audiogram and nonprogressive pure tone thresholds compared with subjects without GJB2 mutations. Subjects with GJB2 mutations and those without GJB2 mutations both showed a similar tendency in speech perception, some aspects of language development, and communication methods. In both groups, development of reading ability tended to be normal, but vocabulary development tended to be delayed. The present results establish the basis for future studies to aid in the evaluation and follow-up of patients with congenital hearing loss associated with GJB2 mutations who are habilitated with hearing aids.

We report a family with inner ear lateral semicircular canal (LSC) malformation and external and middle ear abnormalities. The family had no history of known syndromes or toxic exposures. Distinct phenotypic manifestations were found in three family members. A young girl exhibited bilateral LSC malformation with a right-sided preauricular tag, a mildly deformed auricle, a stenotic external auditory canal, and a constricted middle ear cavity. She had moderate conductive hearing loss in the right ear but normal hearing in the left ear. Her younger brother exhibited right-sided LSC malformation, microtia, external auditory canal atresia, a malformed middle ear cavity, and abnormal auditory ossicles. He had severe mixed hearing loss in his right ear. Their mother exhibited left-sided LSC malformation without external and middle ear abnormalities, and the hearing was normal in her left ear. None of the three cases had vestibular symptoms, and their results of balance tests were appropriate for the corresponding ages. In contrast, significantly decreased LSC function was revealed by caloric tests in an ear with LSC malformation. Previously, LSC malformation may have been underdiagnosed in patients presenting with external and middle ear abnormalities and their relatives, since this malformation is frequently associated with normal hearing and balance or conductive hearing loss only. To our knowledge, this condition has not been described previously. This condition supports a genetic basis for the combination of LSC malformation and external and middle ear abnormalities and may represent an autosomal dominant condition with variable expressivity. KEY WORDS: lateral semicircular canal malformation; external ear malformation; middle ear malformation; hearing loss; autosomal dominant inheritance INTRODUCTIONDevelopmental defects of the first and second branchial arches and the first branchial cleft lead to malformations of the external ear, such as microtia characterized by underdeveloped auricles, stenosis or atresia of the external auditory canal, and preauricular pits, fistulas, and tags [Melnick et al., 1979;Moore and Persaud, 1998]. The prevalence of microtia in different populations ranges from 0.4 to 5.5 per 10,000 births [Allanson, 1995;Mastroiacovo et al., 1995;Calzolari et al., 1999]. This anomaly is most commonly associated with stenosis or atresia of the external auditory canal [Jafek et al., 1975;Kountakis et al., 1995]. Because the external and middle ears share a common embryological origin, concomitant malformation of these structures is also common [Jafek et al., 1975;Swartz and Faerber, 1985;Kountakis et al., 1995;Mayer et al., 1997]. In contrast, malformation of the inner ear is much less frequently associated with external and middle ear abnormalities [Jafek et al., 1975;Mayer et al., 1997], since the inner ear has an independent embryological origin and develops during different gestational period. Among previously described inner ear malformations associated with external and middle ear abnormalities,...

The speech discrimination scores of a 57S word list were analyzed in 180 patients with sensorineural hearing loss. Confusion matrices were made on consonant groups of voiceless, voiced and nasal consonants. In succession, the incidence of consonants was compared between the 57S word list and Japanese conversation. Consonants with high incidence in Japanese conversation were t, h, d, g, m, and n. Patients with sensorineural hearing loss are apt to confuse t and h to k, d to b or r, g to b, d or r, m to n or r, and n to m or r. It is effective to correct these instances of consonant confusion, for improving conversational ability in Japanese patients with sensorineural hearing loss.

No abstract