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Copyright of Acta Oto-Laryngologica is the property of Taylor & Francis Ltd and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Acta Oto-Laryngologica is the property of Taylor & Francis Ltd and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Acta Oto-Laryngologica is the property of Taylor & Francis Ltd and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Purpose: There are many requirements to assess and support individuals with auditory processing disorder (APD); however, there are a few questionnaires that can be employed to detect the listening difficulties experienced by adults who are suspected to have APD. In the present study, we developed a questionnaire to assess the specific listening difficulties of adults and examined the possibility of standardizing this questionnaire in clinical situations. Method: This study included 164 APD adults who had normal hearing, but who complained about listening difficulties encountered during everyday life, and 70 adults who had normal hearing and no complaints about listening difficulties during everyday life. We added four items of the psychological domain to the shortened versions of the Speech, Spatial, and Qualities of Hearing Scale (SSQ-12) for the purpose of assessing the psychological and social reactions to listening difficulties, and we administered it to subjects. Results: The results demonstrated that the questionnaire was a highly sensitive and specific approach and that it was useful in assessing adults with and without APD. This tendency especially increased by combining questions from the SSQ-12 with the psychological domain questions. Conclusion: We suggest that the questionnaire would be used to screen patients in clinical situations and that the results would provide useful information that can aid in understanding the auditory characteristics of people with APD. [ABSTRACT FROM AUTHOR]

Background: The electrically evoked auditory brainstem response (eABR) during cochlear implantation in common cavity (CC) deformity has not been clinically well studied. Aim/Objective: To investigate the eABR wave configuration during cochlear implantation, the postoperative development of hearing, and educational settings in infants with CC deformity. Materials and Methods: Nine infants who were congenitally deaf and found to have CC deformity and suspected cochlear nerve deficiency by temporal bone CT and MRI were studied. All of them underwent sequential and unilateral cochlear implantation and their eABRs were recorded during the surgery. The postoperative development was followed up. Results: eABRs of all the nine infants with CC deformity showed that the mean peak of the evoked wave V (eV) was the same as that in controls at latencies but was twofold higher than that in controls at thresholds and their postoperative hearing thresholds improved markedly. Conclusion and Significance: The brainstem auditory pathways of the infants were considered intact on the basis of the eV peak latencies in the eABRs. The postoperative development of their speech and hearing abilities and their educational settings varied, probably because of the twofold higher thresholds of their eABRs and limited number of auditory neural units. [ABSTRACT FROM AUTHOR]

Background： The function of common cavity deformity demonstrated by temporal bone CT and MRI has been unknown. Aim/Objective: To investigate the developmental changes of vestibular ocular reflex and acquisition of postural control in infants with common cavity deformity. Material and methods: Eight infants who were congenitally deaf complicated by common cavity deformity were studied. The damped rotational chair test was carried out to evaluate vestibular ocular reflex. Acquisition of head control and independent walking in these infants was compared with that in normal infant's milestones of gross motor development. Results: All of the eight infants with common cavity deformity did not show per-rotatory nystagmus in the damped rotational chair test around the first year of life. However, a normal number of beats and a longer duration of per-rotatory nystagmus for their age were recorded at around three or four years of age. Conclusions and significance: In the eight infants with common cavity deformity, vestibular ocular reflex was not present around the first year of life, but appeared after three or four years probably because of some vestibular sensory cells. Head control and independent walking were delayed but eventually acquired by the central vestibular compensation. [ABSTRACT FROM AUTHOR]

Conclusion: Each of eight patients with bilateral microtia and atresia underwent bilateral reconstruction of the auricles and external auditory canals and were fitted bilateral canal-type hearing aids in the operated ears to replace a bone conduction hearing aid. The ability to discriminate inter-aural intensity difference (IID) and even inter-aural time difference (ITD) was retained in all these patients. Objective: This study studied the post-operative sound lateralization ability of patients with bilateral microtia and atresia after total reconstruction of both auricles and external auditory canals, followed by fitting of bilateral canal-type hearing aids. Methods: Eight patients with bilateral microtia and atresia ranging in age from 13–43 years were recruited in this study. Each of them underwent bilateral reconstruction of the auricles and external auditory canals and were fitted canal-type hearing aids in both the operated ears to replace a bone conduction hearing aid. A sound lateralization test was conducted to determine IID and ITD discrimination ability thresholds. Results: In all the patients, the IID discrimination ability thresholds of the patients were more than 3-fold those of the controls, the ITD discrimination ability threshold was more than 5-fold those of controls, and binaural hearing was retained. [ABSTRACT FROM AUTHOR]

Conclusion: In patients with unilateral microtia and atresia after reconstruction of the auricle and external canal and fitting of a canal-type hearing aid for the operated ear, the ability to discriminate the inter-aural intensity difference (IID) was acquired in all of the patients, whereas that to discriminate inter-aural time difference (ITD) was acquired in one-half of the patients. Objective: To study the post-operative sound lateralization ability in patients with unilateral microtia and atresia after reconstruction surgery of the auricle and external canal and fitting of a canal-type hearing aid of the operated ear. Methods: Eighteen patients with unilateral microtia and atresia ranging from 13–24 years of age were recruited in this study. All of them underwent reconstruction of the auricle and external canal and were fitted a canal-type hearing aid for the operated ear. The sound lateralization test was conducted to determine IID and ITD using a self-recording apparatus. The test stimulus was a continuous narrow-band noise at 500 Hz and 50 dBHL presented to the right and left ears through the air conduction receivers. Results: IID could be measured in all of the patients, whereas ITD could be measured in only nine out of the 18 patients. Post-operative binaural hearing could be acquired in all the patients. [ABSTRACT FROM AUTHOR]

Conclusions: The functional connectivity (FC) between the right and left auditory cortex is weak in tinnitus patients. Transcranial direct current stimulation (tDCS) over the auditory cortex has potential as a tool to modulate auditory-based FC. Objective: This study investigated the effects of applying tDCS in tinnitus patients, and searched for modulation of brain networks in resting-state functional magnetic resonance imaging (rs-fMRI) through an analysis of FC with the stimulated brain region. Subjects and methods: Nine male patients with chronic tinnitus and 10 male volunteers with normal hearing were enrolled. The subjects were evaluated with rs-fMRI immediately before and after tDCS. The tinnitus patients filled out the self-evaluation questionnaires designed to measure tinnitus conditions before tDCS treatment and 1 week afterwards. Results: The FC between the right and left auditory cortex was significantly weaker in tinnitus patients than in controls. After tDCS treatment, in the tinnitus group, the primary auditory cortex showed a reduction in the amount of statistically significant connectivity with the somatosensory area and motor area, but maintained strong significant connectivity (p < 0.005) with the auditory area and insular cortex. In contrast, in the control group, there remained strong significant connectivity between the primary auditory cortex and the somatosensory area, motor area, insular cortex, and auditory area. [ABSTRACT FROM AUTHOR]

Conclusions:EABR is a reliable and effective way of objectively confirming device function and implant-responsiveness of the peripheral auditory neurons up to the level of the brainstem in cases of inner ear malformation.Objective:To investigate the usefulness of measuring the intra-operative electrically evoked compound action potential (ECAP) and electrically evoked auditory brainstem response (EABR) in patients with and without congenital inner ear anomalies during cochlear implantation.Method:Thirty-eight consecutive children (40 ears) aged 5 or younger with congenital profound hearing loss. Twenty-four (25 ears) lacked congenital inner ear anomalies. The 14 patients (15 ears) with a malformation had common cavities (four ears), incomplete partition type I (three ears), cochlea hypoplasia type III (three ears), enlarged vestibular aqueduct (four ears), and cochlear nerve canal stenosis (one ear). Main outcome measures are ECAP and EABR responses.Results:Of the 25 ears lacking any malformation, 21, three, and one showed ‘Good’, ‘Variable’, and ‘No’ ECAP responses, respectively, and 24 and one showed ‘Good’ and ‘Variable’ intra-cochlear responses, respectively. Of the 15 ears with a malformation, two showed ‘Good’ ECAP responses, nine had ‘Variable’ ECAP responses, and four showed ‘No’ ECAP responses. Moreover, five showed ‘Good’ EABR responses and 10 showed ‘Variable’ EABR responses. [ABSTRACT FROM PUBLISHER]

Conclusion: A right-handed 38-year-old man's complete loss of hearing could be diagnosed as cortical deafness caused by cerebral vascular lesions in bilateral auditory cortices. Objective: The aim of this case report was to study the pathophysiology of a particular patient who manifested deafness without residual hearing and lost somatosensory sensation, vestibular sensation, and articulation ability after a right internal carotid-posterior communicating artery (IC-PC) aneurysm and subarachnoidal hemorrhage. Methods: MRI, aphasia and neurological tests, subjective and objective audiometry, and vestibular function tests were performed. Results: The neurological test revealed system loss of somatosensory sensation with normal motor function and articulation ability. Brain imaging revealed extensive infarction in the bilateral primary auditory cortices, postcentral gyruses, and the bilateral partial third frontal gyruses. Pure-tone audiometry of both ears revealed off-the-scale results and speech audiometry demonstrated 0% maximum speech discrimination. However, objective audiometry showed normal distortion product otoacoustic emissions (DPOAE) and normal auditory brainstem response (ABR). The patient showed 0% perception of environmental, speech, and music sounds in both ears. He was unable to feel vestibular sensation despite normal caloric nystagmus. He showed no damage to his larynx or articulation organs. [ABSTRACT FROM AUTHOR]

Conclusions: When vestibular function is reduced in the rotational chair test in children with severe hearing loss, the vestibular function may be acquired later due to maturing vestibular sensory cells and vestibular nerve of the inner ear along with physical growth. Objectives: To examine the relationship between acquisition of motor function and vestibular function in children with bilateral severe hearing loss. Methods: A total of 97 children under 4 years old with hearing loss defined as a hearing threshold of both ears greater than 80 dB were included in this study. For evaluation of vestibular function, a damped-rotational chair test was performed and the horizontal nystagmus was recorded using electronystagmography (ENG). Results: Head control and independent walking were delayed in 28 of 97 children with severe hearing loss. Reduced response to the rotational chair test was observed in 16 of 97 children (16.5%), with 11 of these children having inner ear anomalies and reduced vestibular function. Of the 10 children who were followed up by the rotational chair test, 2 children with idiopathic congenital hearing loss without inner ear anomalies (100%) and 6 of 8 children with bilateral inner ear anomalies (75%) showed more obvious nystagmus during rotation compared with the initial examination. [ABSTRACT FROM AUTHOR]

Pelizaeus-Merzbacher disease (PMD) is a white matter dystrophy of the brain. Most children with PMD require comprehensive nursing care. Their speech and language abilities are poor or absent. Therefore, evaluating hearing ability is difficult in children with PMD. We have followed up two patients with PMD since early childhood. Patient 1 is an 11-year-old boy, and patient 2 is a 15-year-old adolescent boy in whom horizontal nystagmus was recognized after birth. Magnetic resonance imaging showed diffuse dysmyelination of the cerebral white matter. Auditory brainstem response recordings showed only waves I and II and the absence of all subsequent components. However, conditioned orientation reflex audiometry showed a threshold of 20-30 dB. Both patients can converse orally and have auditory perception and speech abilities better than those of most patients with PMD in the literature. We report on the development of their hearing and speech abilities. [ABSTRACT FROM AUTHOR]

The case of an 8-year-old girl who manifested cortical blindness and whose color drawings of faces and objects were without outlines is reported. Her birth was uneventful. When she was 10 months old, she fell down to the floor from a chair, resulting in a subarachnoidal hemorrhage. A repeat brain MRI revealed localized lesions in the visual cortices in the right and left hemispheres. As she grew older she was found to have visual imperceptions. She was found to have difficulties in learning visually the names of objects with form and letters, and in recognizing faces of her family. However, she was able to discriminate well the colors of faces and objects and learn easily the names of the objects with form by touching. She seemed to utilize subcortical vision for seeing colors of faces and objects. [ABSTRACT FROM AUTHOR]

A 27-year-old female showed auditory agnosia after long-term severe hydrocephalus due to congenital spina bifida. After years of hydrocephalus, she gradually suffered from hearing loss in her right ear at 19 years of age, followed by her left ear. During the time when she retained some ability to hear, she experienced severe difficulty in distinguishing verbal, environmental, and musical instrumental sounds. However, her auditory brainstem response and distortion product otoacoustic emissions were largely intact in the left ear. Her bilateral auditory cortices were preserved, as shown by neuroimaging, whereas her auditory radiations were severely damaged owing to progressive hydrocephalus. Although she had a complete bilateral hearing loss, she felt great pleasure when exposed to music. After years of self-training to read lips, she regained fluent ability to communicate. Clinical manifestations of this patient indicate that auditory agnosia can occur after long-term hydrocephalus due to spina bifida; the secondary auditory pathway may play a role in both auditory perception and hearing rehabilitation. [ABSTRACT FROM AUTHOR]

The influence of aging on hearing and vestibular function in patients with auditory neuropathy has not been investigated. The purpose of this study was to investigate how hearing and vestibular function in this disease change with aging. The subjects were three female patients with auditory neuropathy. We checked their hearing and vestibular function by speech discrimination tests, ABR, ECochG, DPOAE, caloric test, damped-rotational chair test, and VEMPs. In all three patients, speech discrimination ability and vestibular function markedly declined with aging. However, speech language understanding and higher brain function were less affected by aging. [ABSTRACT FROM AUTHOR]

In 1999, three workers received high doses of radiation in a small Japanese plant while they were preparing fuel for an experimental reactor. This criticality accident at melting point was caused by the addition of too much uranium enriched to a relatively high level, causing a ''criticality'' (a limited uncontrolled nuclear chain reaction), which continued intermittently for 20 h. The three workers concerned were hospitalized, two in a critical condition. The first worker died 12 weeks later, and the second worker 7 months later. The third worker is in a healthy condition. We report on the temporal bone histopathological features of the second worker. Our temporal bone study revealed: 1) the large loss of bone marrow tissue with a small number of myelocytes remaining in the mastoid bone and the abundance of fatty tissue in the mastoid bone, 2) inflammation of the mucosal layer of the middle ear and the mastoid air cells, 3) mild degeneration of the spiral ganglions and the sensory hair cells of the cochlea, 4) mild degenerative changes of sensory hair cells of the semicircular canals and otolith organs, and 5) vestibular ganglions and geniculate ganglions were well preserved. [ABSTRACT FROM AUTHOR]

Conclusion: GJB2 mutations are responsible not only for deafness but also for the occurrence of vestibular dysfunction. However, vestibular dysfunction tends to be unilateral and less severe in comparison with that of bilateral deafness. Objectives: The correlation between the cochlear and vestibular end-organs suggests that some children with congenital deafness may have vestibular impairments. On the other hand, GJB2 gene mutations are the most common cause of nonsyndromic deafness. The vestibular function of patients with congenital deafness (CD), which is related to GJB2 gene mutation, remains to be elucidated. The purpose of this study was to analyze the relationship between GJB2 gene mutation and vestibular dysfunction in adults with CD. Methods: A total of 31 subjects, including 10 healthy volunteers and 21 patients with CD, were enrolled in the study. A hearing test and genetic analysis were performed. The vestibular evoked myogenic potentials (VEMPs) were measured and a caloric test was performed to assess the vestibular function. The percentage of vestibular dysfunction was then statistically analyzed. Results: The hearing level of all CD patients demonstrated a severe to profound impairment. In seven CD patients, their hearing impairment was related to GJB2 mutation. Five of the seven patients with CD related to GJB2 mutation demonstrated abnormalities in one or both of the two tests. The percentage of vestibular dysfunction of the patients with CD related to GJB2 mutation was statistically higher than in patients with CD unrelated to GJB2 mutation and in healthy controls. [ABSTRACT FROM AUTHOR]

Conclusions: Our study revealed that VEMPs in responses to clicks and 500 Hz STB were abnormal in 25% of athletes with congenital profound sensorineural hearing loss for the Deaf Olympic Games. These results confirm that a part of deaf athletes with congenital vestibular failure is well compensated for higher level sport activities. Objectives: The aim of this study was to investigate the appearance rate of VEMP, vestibular failure and its compensation in Japanese deaf athletes by the VEMP test, caloric test and balance test. Methods: Sixteen subjects among the Deaf Olympic Games athletes of Japan volunteered to participate in this study. All the subjects have congenital profound sensorineural hearing loss. Results: In the VEMP test, 24 ears (75%) showed normal click-evoked responses, 5 ears (16%) showed decreased click-evoked responses, 3 ears (9%) showed no click-evoked responses, 28 ears (87.5%) showed normal 500 Hz short tone burst (STB)-evoked responses and 4 ears (12.5%) showed decreased responses. In the ice-water caloric test, 11 subjects (69%) showed normal responses bilaterally, 3 subjects showed bilateral responses with asymmetrical responses and 2 subjects (12%) showed no response bilaterally. All the subjects showed normal balance test results. [ABSTRACT FROM AUTHOR]

Conclusions: Our results show that among the patients with inner ear malformations, there were two patients with sensory cells of sacculus and inferior vestibular neurons and at least five patients with inferior vestibular neurons only, but no patients without sensory cells and vestibular neurons, as determined on the basis of vestibular evoked myogenic potentials (VEMPs). Objective: The aim of this study was to investigate whether sensory cells of sacculus or inferior vestibular neurons or both are present in cochlear implant patients with inner ear malformations, particularly common cavity (CC) deformity, using VEMPs. Patients and methods: Seven children with inner ear malformation who underwent cochlear implantation (CI) participated in this study. The patients had CC deformity ( n=2), incomplete partition type I ( n=2), incomplete partition type II ( n=1), or a narrow internal auditory canal (IAC) ( n=2). It was possible to record VEMPs before and after CI in three patients and not before but after CI in four patients. After surgery, VEMPs were recorded with the cochlear implant device switched both off and on. Results: Before the CI, two patients showed VEMPs and one patient showed no VEMPs, whereas in four patients no VEMPs could be recorded. All the patients showed VEMPs with the cochlear implant on. [ABSTRACT FROM AUTHOR]

Conclusion: We regard spontaneous otoacoustic emission (SOAE) as a unique phenomenon due to spontaneous outer hair cell hyperactivity during the infantile period in these two infants. Objectives: We report the cases of SOAEs in two infants, which were audible to their parents. We were able to hear continuous sounds from these two infants' ears. We studied their hearing and the emitted sounds objectively. Patients and methods: Patient 1 was a 5-month-old girl and patient 2 was an 11-month-old girl. Their parents heard continuous sounds emanating from their infants' ears. Audiological examinations and frequency analysis were conducted. Results: The distortion-product otoacoustic emissions (DPOAEs) and auditory brainstem responses (ABRs) of the two patients were normal. Analysis of the continuous sounds demonstrated frequencies of 4.2 and 6.5 kHz for patient 1 and 6.7 kHz for patient 2. These audible sounds were diagnosed as SOAEs. The SOAEs in these infants did not disappear with their development in the last 2 years. [ABSTRACT FROM AUTHOR]

Congenitally deaf infants and children commonly suffer vestibular failure in both ears, and impairment of postural control, locomotion, and gait. The development of gross motor functions, such as head control, sitting, and walking is likely to be delayed, but fine motor function is usually preserved unless disorders of the central nervous system are present. These children can eventually catch up with their normal peers in terms of development and growth as a result of central vestibular compensation. The visual and somatosensory systems, pyramidal and extrapyramidal motor system (cerebellum, basal ganglia, cerebrum) and intellectual development, compensate for vestibular failure in infants and children with congenitally hypoactive or absent function of the semicircular canals and otolith organs. [ABSTRACT FROM AUTHOR]

Conclusions. This study showed that delayed auditory pathway myelination is common in Pelizaeus-Merzbacher disease (PMD), but this delay does not necessarily indicate poor hearing function. Objective. PMD is a rare recessively inherited X-linked leukodystrophy characterized by defective central nervous system myelination owing to a mutation in the proteolipid protein gene (PLP). The aims of this study were to evaluate the hearing function and auditory brain response (ABR) findings of patients with PMD and relate these findings to MRI-assessed myelination in the central auditory pathway. Patients and methods. We retrospectively studied eight male pediatric patients with PMD. Serial auditory examinations included audiometry, behavior audiometry, distortion product otoacoustic emission (DPOAE), and ABR. MRI-assessed myelination in the auditory pathway was evaluated in the PMD patients and in 23 normal young children as a control group. Results. Audiometry showed normal to moderate hearing impairment and the hearing threshold improved with age and became almost normal over time. DPOAEs positivity and only ABR wave I or waves I and II were found in all the patients. MRI showed delayed myelination in all the patients and the auditory pathway was myelinated up to the inferior colliculus in four cases and up to the medial geniculate body in four cases. Serial MRIs showed no progression in myelination. No clear relation was found between hearing threshold and MRI-assessed myelination in the auditory pathway. [ABSTRACT FROM AUTHOR]

Conclusions. This study showed that vestibular evoked myogenic potentials (VEMPs) evoked by cochlear implant (CI), could be related to the comfortable level (C level), particularly in the channels that are closer to the apical turn of the cochlea. Objective. The purpose of this study was to investigate the correlation between VEMPs and C level of each channel. Subjects and methods. We investigated 24 children who underwent cochlear implantation. VEMPs were recorded from the operated ears with the CI switched 'off' or 'on'. To investigate the correlation between VEMPs and C level, we selected 13 patients with Nucleus 24 (SPrint), and divided them into group A (normal VEMPs) and B (absence of VEMPs). In these children, all the 22 electrodes were active, and were mapped in the same frequency range for each channel. Results. Twenty children (83%) showed no VEMPs with the CI 'off'. Among them, 10 elicited VEMPs with the CI 'on', but the other 10 did not. In all channels, the mean C levels of CI were higher in group A than in group B. The p values in channels 1-12 were >0.10, in channels 13-16 were 0.06-0.09, and in channels 17-22 were 0.05-0.06, which were lower but not statistically significant. [ABSTRACT FROM AUTHOR]

Conclusions. The horizontal portion of the petrous carotid artery (HPCA) of mandibulofacial dysostosis (MFD) patients had anterior-inferior displacement or was aplasia at birth. Our findings indicate that most MFD patients have aplasia of the internal carotid artery. This information may be very important for safe reconstruction surgery in atresia. Objective. MFD rarely has malformations of the cardiovascular system such as those seen in Goldenhar syndrome. This study aimed to compare MFD patients and normal subjects with respect to the length and diameter of the HPCA. Subjects and methods. We radiographically studied 22 MFD patients (44 sides) using high-resolution computed tomography (HRCT), measuring the length and diameter of the HPCA and the angle between the right and left HPCA using computer software. Findings were compared with those in 86 ears with normal auricles (control group) using the nonparametric test. Results. The HPCA in MFD patients averaged 23.2 mm in length and 4.8 mm in diameter. The angle between the right and left HPCA averaged 100.2°. In MFD patients, on average, HPCA were 2.0 mm shorter (p=0.001) and 0.4 mm narrower (p=0.016) than in control subjects. Mean angle between right and left HPCA was 5.4° more acute in MFD patients than in control subjects (p=0.026). Moreover, the genu of the vertical and horizontal petrous ICA in the MFD group was on average 3.2 mm more inferior than in controls (p<0.001). [ABSTRACT FROM AUTHOR]

Conclusion. The early diagnosis of deafness and the early fitting of hearing aids in multiply handicapped children are recommended for language development in these children even when their neurological or mental status is poor. Subjects and methods. The subjects consisted of 5 hearing-impaired infants with no other problems and 28 hearing-impaired children with multiple handicaps. Behavioral audiometry and auditory brainstem responses were used for evaluating hearing impairment. The 5 hearing-impaired infants with no other problems underwent hearing aid fitting at approximately 1 year of age and the 28 hearing-impaired children with multiple handicaps underwent hearing aid fitting at various times from 1 to 5 years of age. The effects of their hearing aids were compared on the basis of auditory behavioral changes. The developmental scale of auditory behaviors in infancy that we proposed was introduced to evaluate the development of auditory behaviors. Results. The auditory behaviors of the hearing-impaired children with no other problems showed constant changes with age after hearing aid fitting. However, among the 28 hearing-impaired children with multiple handicaps, 17 showed improvement in auditory behaviors, 5 showed no improvement in auditory behaviors because of the associated severe motor and mental retardation, and epilepsy, and 6 were unable to adapt to wearing hearing aids. [ABSTRACT FROM AUTHOR]

Conclusion. Among mass lesions inside the temporal bone, benign tumors and cholesteatomas can be differentiated by contrast enhancement in T1-weighted images (T1WI) and by diffusion-weighted images (DWI). Moreover, DWI will also facilitate discrimination between cholesteatomas accompanied by granulation and other non-neoplastic lesions such as mucoceles and cholesterol granulomas. Objectives. To review the imaging characteristics of mass lesions inside the temporal bone and to investigate pertinent imaging modalities for differential diagnosis, which is crucial for appropriate treatment planning. Patients and methods. This was a retrospective case series study of six patients seen between 2002 and 2005 with mass lesions deep inside the temporal bone. Results. One patient had facial schwannoma, two had glomus jugulare tumor, and three had cholesteatoma. Plain high resolution CT gave few clues to the nature of the mass lesions. MRI study provided us with better clues: contrast enhancement on T1WI was observed only in benign tumors and only cholesteatomas showed high intensity on DWI. With the assistance of neurosurgeons, surgery was successfully performed in all cases. [ABSTRACT FROM AUTHOR]

The vertebrate inner ear is derived from the otic placode and undergoes a complicated series of morphogenetic processes to differentiate into an elaborate structure harboring mechanosensory epithelia featuring hair cells, the mechanoreceptors of hearing and balance. Recently, the principal mechanisms producing hair cells and the key molecules involved in their fate determination and differentiation have been gradually unveiled. The in-depth understanding of hair cell development is consequently providing clues to strategies for mammalian hair cell regeneration. Among them, the identification and characterization of progenitor cells for the hair cell lineage, which is just emerging, is of particular interest. Herein, we review the molecular mechanisms of inner ear development with particular focus on perspectives for hair cell regeneration. [ABSTRACT FROM AUTHOR]

Conclusion. Tumors developing into the muscle layer and tumor thickness ≥5 mm are the most important risk factors associated with nodal metastasis. Objective. It is necessary to identify the risk factors associated with cervical metastasis in patients with oral floor cancer to reveal the role of elective neck dissection for oral floor cancer. Patients and methods. Forty-eight patients with oral floor cancer were retrospectively analyzed for a correlation between clinicopathologic factors and cervical lymph node metastasis using Fisher's exact test and a logistic regression test. Results. Univariate analysis showed significantly positive correlations for growth type, mitosis, perineural invasion, vascular invasion, lymphatic invasion, depth, thickness, and infiltration growth ratio. Multivariate analysis had a significantly positive correlation with nest formation and depth in all patients, and with thickness in patients with T1 or T2. In patients with bilateral cervical lymph node metastasis, lymph node metastasis was significantly positively correlated with perineural invasion. [ABSTRACT FROM AUTHOR]

Conclusion. This study illustrates common sites of infection seen in peritonsillar abscesses with involvement of the pharyngeal space and retropharyngeal space. Abscesses behind and/or inferior to the tonsil were encountered more frequently than expected. In these cases, the drainage had to be placed in the inferior pole of the tonsil and these types were frequently seen in older patients. Objectives. The aim of this study was to assess to what extent abscesses spread in patients with peritonsillar abscess and to determine to what extent pus can be drained intraorally. Patients and methods. The clinical charts of 45 patients with peritonsillar abscess involvement of the parapharyngeal space and/or retropharyngeal space were retrospectively reviewed. Results. In 45 cases, 21 patients were diagnosed with the superior type, and we could drain the pus intraorally in 90% of the patients. On the other hand, 24 cases were diagnosed with the inferior type and they were drained intraorally in 58% of the cases. [ABSTRACT FROM AUTHOR]

Conclusions. Endoscopic intranasal dacryocystorhinostomy (DCR) has the following advantages over external surgery: pain and hemorrhage are minimal; postoperative facial swelling and scarring are absent; and symptoms resolve rapidly after surgery. Furthermore, as no significant differences in postoperative results were apparent between external and endoscopic intranasal DCR, and because no facial skin incision is required, the clinical usefulness of endoscopic intranasal DCR is high. Objectives. In the treatment of nasolacrimal duct obstruction or chronic dacryocystitis in which epiphora or ocular discharge are chief complaints, endoscopic intranasal DCR is a safe, easy, minimally invasive, and reliable approach. In the present study, we describe the surgical procedures, techniques, and results of endoscopic intranasal DCR, and investigate its clinical usefulness. Subjects and methods. The subjects were 21 patients with nasolacrimal duct obstruction who underwent a total of 24 endoscopic intranasal DCR procedures. Etiologies of the obstruction were, respectively, cryptogenic (62.5%), secondary to partial maxillectomy (16.7%), complication of sinus surgery (12.5%), and due to underlying disease - Wegener's granulomatosis (4.2%) or nasal T-cell lymphoma (4.2%). To assess the clinical usefulness of this procedure, postoperative courses were assessed by reviewing medical records and conducting telephone interviews. In addition, to assess the therapeutic effects, postoperative results were statistically compared to those of external DCR. Results. Closure of the surgical opening was seen in two cases (8.3%). In both cases, after the closed region was opened using an endoscopic procedure, symptoms resolved. Finally, lacrimal passage obstruction was not observed by lacrimal irrigation in any patient. None of the patients in the present study experienced major complications during or after surgery, and since their symptoms improved, the degree of satisfaction was high. When compared to external DCR, endoscopic intranasal DCR showed no statistically significant difference in postoperative results, thus confirming that similar therapeutic effects could be obtained for the two procedures. [ABSTRACT FROM AUTHOR]

Conclusion. This study suggested that nitric oxide (NO) takes part in the parasympathetic nerve control functions mainly through m3 receptors and subsequently through m1 receptors. Objectives. The regulation of glandular secretions and vasomotor tone in human nasal mucosa implicates muscarinic receptors. There are five recognized classes (m1-m5) of muscarinic receptor subtypes. NO is a free radical gas that has been found to be produced in neuronal cells by the action of enzyme neural nitric oxide synthase (nNOS). The aim of this study was to identify the colocalization of muscarinic receptor subtypes (m1-m5) and nNOS in the human inferior turbinate mucosa. Materials and methods. Human inferior turbinate mucosa was stained by using the antibody of muscarine receptor subtypes and nNOS in an immunohistochemical double-staining method. Results. The colocalization of m3 receptors and nNOS-immunoreactive nerve fibers was most extensively distributed on glands, vessels, and epithelium in all muscarinic receptor subtypes. These findings lead us to propose that NO also acts as a neurotransmitter in glands, vessels, and epithelium of the human nasal mucosa and can be assigned to parasympathetic nerve structures through m3 receptors mainly and m1 receptors subsequently. [ABSTRACT FROM AUTHOR]

Conclusion. The present study demonstrated the age-related decrease in the axonal diameter of the olfactory nerve. This finding may represent the maturational change of the olfactory receptor neurons. Objectives. The aim of this study was to investigate age-related changes in the axonal diameter of the olfactory nerve in the lamina propria. Materials and methods. Female ICR mice, postnatal age 10 days, 3 months, 7 months, and 16 months, were studied. The electron micrographs of septal olfactory mucosa were used to measure the axonal diameters of olfactory nerves. Results. The distribution of the diameter shifted toward the thinner side between 10-day-old and 3-month-old mice. The axonal diameter showed significant decreases (p < 0.001) from the age of 10 days to that of 3 months. [ABSTRACT FROM AUTHOR]

Conclusions. The proportion of drug-resistant bacteria was lower than previous reports. In children with acute otitis media (AOM), lower age, presence of multiple bacteria, and otitis media with effusion (OME) represented significant factors for recurrent AOM and the presence of drug-resistant bacteria. Objective. Recently, the proportion of drug-resistant bacteria has been increasing in children with AOM. We studied the proportion of drug-resistant bacteria and background factors for detection of drug-resistant bacteria and recurrent AOM in a private clinic. Subjects and methods. Subjects comprised 170 patients <12 years old with AOM. Middle ear fluid was collected and pathogenic bacteria were identified. The following factors were considered: age, sex, use of antibiotics in the past 1 month, past history of recurrent AOM, presence of OME, and multiple bacteria of the three main strains (Streptococcus pneumoniae, Haemophilus influenzae, and Moraxella catarrhalis). Results. A total of 169 strains were detected in 77% of children with AOM. Drug-resistant bacteria comprised 44 of the 169 strains (26%). Lower age (p=0.001) and presence of multiple bacteria (p<0.001) represented significant factors for the presence of drug-resistant bacteria. OME was a significant factor for recurrent AOM (p<0.001). [ABSTRACT FROM AUTHOR]

Multiple system atrophy (MSA) is a progressive neurodegenerative disease that is characterized by varying degrees of parkinsonism and cerebellar, corticospinal, and autonomic dysfunction. Vocal cord abductor paralysis (VCAP) is considered a sign of a poor prognosis in MSA, because it is a life-threatening complication that may cause nocturnal sudden death. This case report presents a patient who was treated for Parkinson's disease, and complained of dizziness and sleep apnea. We examined VCAP using fiberoptic laryngoscopy as the possible cause of sleep apnea. VCAP usually occurs in the advanced stages of MSA and is accompanied by a worsening of other symptoms. Optokinetic nystagmus was severely impaired and the caloric test response was bilaterally absent. Objective findings such as VCAP and abnormal neuro-otological results led to the diagnosis of MSA. [ABSTRACT FROM AUTHOR]

We report a case in which metastasis occurred from a left-side maxillary carcinoma to bilateral temporal bones through different routes, manifested by rapidly progressing left-side mixed hearing loss, left-side vestibular dysfunction, and serous otitis media. Later the left-side hearing threshold became severely elevated, suggesting profound sensory hearing loss. Histopathology of the temporal bones revealed that the side with the lesion was severely damaged by tumor through direct and hematogenous metastasis. On the contralateral side, it showed four findings: (i) sparse and separate tumor invasion of the petrous bone, the mastoid cavity, and the facial canal (hematogenous spread); (ii) tumor involvement in the lower part of the cochlear aqueduct without invasion of the internal acoustic canal or cochlea, implying early meningeal carcinomatosis; (iii) vascular stria atrophy, spiral ganglion diminution, and well preserved hair cells; and (iv) diffuse effusion in the middle ear and mastoid cavity. Our observations revealed that tumor cells dispersed to the same side through different routes, whereas early metastasis to the contralateral side was mainly through hematogenous and subarachnoid spread. [ABSTRACT FROM AUTHOR]

This report shows the changes that occurred in consecutive audiograms of a patient who underwent chemotherapy and radiotherapy for nasopharyngeal cancer and the histopathological examination of the temporal bones. Both conductive and sensorineural hearing loss developed, but followed different modes of progression. In the left ear, an air-bone gap appeared and deepened, while in the right ear, severe conductive hearing loss was present upon admission and improved after treatment. Sensorineural hearing loss was worse in the right ear, but deteriorated gradually in both ears. Histology revealed tumor invasion in the right temporal bone. Both middle ears showed effusion, but no radiation-induced changes that may be responsible for the conductive loss. The main changes in the cochlea were vascular stria degeneration, spiral ligament atrophy, and spiral ganglion cell depletion, while the hair cells were only occasionally missing. Apart from confirming what has been established previously by other authors, some interesting findings were observed: 1) in addition to the high frequency hearing loss typically caused by cis-platinum and by radiation, there was also low frequency hearing loss, and 2) the cochlear damage was most severe in the vascular stria and spiral ganglions, sparing the hair cells. [ABSTRACT FROM AUTHOR]

Conclusions. While infants under the age of 1 year exhibited a high rate of abnormal intensities in the middle ear and mastoid cavities, older infants showed no abnormal intensities in these regions. From the signal intensity on T1- and T2-weighted MRI, the abnormal intensities in the middle ear cavity were considered to represent liquid effusion. Taken together with the findings of temporal bone CT, the abnormal intensities in the mastoid cavity were considered to represent bone marrow. Objective. Histopathological studies of the temporal bone and tympanometry investigations have reported the presence of mesenchyme and liquid effusion in the middle ear cavity of infants. However, very few CT or MRI middle ear cavity findings of newborns and infants have been published, and none have included the mastoid cavity. We therefore performed an MRI study of the middle ear and mastoid cavities of infants under 2 years old (83 cases, 88 imaging series). Subjects and methods. MRI (1.5 T) was originally performed on suspicion of brain disorders in infants aged under 2 years. All MRI slices were studied and classified on the basis of the distribution of abnormal intensities in the middle ear and mastoid cavities. Results. All the abnormal imaging appeared in infants under 1 year old, in particular, 74.24% (n=49) of abnormal imaging appeared in the first 20 weeks after birth. [ABSTRACT FROM AUTHOR]

Conclusions. The vestibular function can be assessed by ice-water caloric test, rotational chair test and VEMP recording in severely hearing impaired infants and young children, and 85% of these patients showed abnormal responses in these tests. Objectives. To evaluate the vestibular function of infants and young children with congenital and acquired deafness, we examined the semicircular canal and otolith function in their early childhood. Materials and methods. Our subjects were 20 children (11 boys, 9 girls; age range 31-97 months, mean age 54.2 months) with severe hearing impairment. Their vestibular functions were assessed by the ice-water caloric test, rotational chair test and vestibular-evoked myogenic potential (VEMP) recording. Results. Among these 20 severely hearing impaired children, only 3 (15%) showed normal responses in the caloric test, rotational chair test and VEMP recording bilaterally. Seven (35%) showed responses asymmetrically in the caloric test despite normal responses in the rotational chair test and VEMP recording bilaterally. Five (25%) showed hyporeflexia or areflexia in the caloric test bilaterally, but showed normal responses in the rotational chair test and normal reproducible or decreased VEMPs. Five (25%) showed no responses at all in the caloric test, rotational chair test and VEMP recording. [ABSTRACT FROM AUTHOR]

The relationship between meningitis and sensorineural hearing loss (SNHL) has long been studied. Many histopathological studies of animal models and human temporal bones with respect to bacterial meningitis have been carried out. However, the relationship between SNHL and tuberculous meningitis was seldom addressed and the pathophysiology remains unclear. We carried out temporal bone studies on material from a 22-year-old patient who developed a right unilateral SNHL before dying from tuberculous meningitis. The histopathological findings for the right temporal bone were as follows: (1) inflammation mainly appeared in the internal auditory canal, modiolus and Rosenthal's canal and extended to the osseous spiral ligament, whereas the perilymphatic spaces were less involved; (2) the organ of Corti, cochlear nerve fibres and spiral ganglion cells were severely degenerated, particularly in the basal and middle turns; (3) the contralateral side (for which the patient had no complaints) showed an inner space free from inflammation, but some granulomatous formations were observed in the middle ear cavity. We conclude that the modiolus and cochlear aqueduct are the main routes for the spread of infection from the meninges to the inner ear. The progression of hearing loss resembles that of bacterial meningitis and shares attributes of retrocochlear SNHL. [ABSTRACT FROM AUTHOR]

Conclusions: Patients treated by mastoidectomy in the past often present with hearing loss and cavity problems such as pus discharge. Total middle ear reconstruction (TMER) improves the hearing of these patients by correcting cavity problems and resolution of ear discharge, which facilitates ossicular chain reconstruction such as type III or type IV tympanoplasty. Objective: To evaluate the effectiveness of TMER in improving hearing. Patients and methods: We reviewed the audiograms of 56 ears of 48 patients who underwent TMER in combination with either type III or type IV tympanoplasty. Audiometric pure tone thresholds averaged over three frequencies (500, 1000, and 2000, pure tone average) were measured and compared before and after surgery. Successful outcome was defined as improvement of 15 dB or more. The mean follow-up was 5.7 years (range 1.1-12.6). We also analyzed the relations between hearing improvement and factors such as type of tympanoplasty (types III and IV), choice between one-stage and two-stage operation, and the interval between original mastoidectomy and final operation. Results: The mean hearing gain was 13.6 (±11.9) dB. Twenty-seven procedures (48.2%) were considered successful, with improvement of 15 dB or more. The results of type III tympanoplasty group were significantly superior to those of type IV (p<0.05, Student's t test). One- and two-stage surgery did not significantly influence outcome. The interval between the initial operation correlated weakly and negatively (r = - 0.266, p<0.05) with hearing gain. [ABSTRACT FROM AUTHOR]

Conclusions . A new giant magnetostrictive bone conduction transducer (GMT) measuring 8 mm (length) by 2 mm (diameter) is capable of outputting sounds over a wider range of frequencies than conventional electromagnetic transducers (EMTs). The GMT can vibrate the rat skull about 3–100 times faster than the EMT, especially above 2 kHz. Objectives . Since the GMT can generate high sound quality and output sounds above 10 kHz, we investigated the width of the frequency response of the GMT and evaluated its mechanical performance. Materials and methods . We chose Wistar rats to estimate the GMT performance by measuring the bone-conducted ABR and the skull vibratory velocity because their hearing frequency range extends from 0.15 kHz to 67 kHz. We also measured the bone-conducted auditory brainstem responses (ABRs) and the skull vibratory velocity of rats with the EMT. Skull vibratory velocity was measured with a laser Doppler vibrometer (LDV). Results . The skull vibratory velocity at the ABR threshold obtained with each transducer was within the -35 to -50 dB range (0 dB re 1 mm/s). When 1 Vpp was applied to each transducer, the GMT had a higher velocity at frequencies of 2–30 kHz, and the EMT at frequencies of 0.5–1 kHz. [ABSTRACT FROM AUTHOR]

Conclusions. Our results suggest that the sacculi of most children with cochlear implants can easily be damaged, as shown by the absence of vestibular-evoked myogenic potentials (VEMPs) in response to click stimuli. Also, in most of the children, the vestibular nerve was seemingly not stimulated by the cochlear implant. These results suggest that electrical stimulation at the C level can stimulate the cochlear nerve; however, this stimulation did not spread to the vestibular nerve in our children. In some children with Mondini dysplasia or vestibulocochlear nerve abnormality, the vestibular nerve was stimulated when the cochlear implant device was on, because of a VEMP response to electrical stimulation. Objective. To clarify the diagnostic value of VEMPs in cochlear implant patients. Material and methods. The click-evoked myogenic potentials of 12 children who underwent cochlear implantation surgery were investigated. The latency and amplitude of the VEMP responses were measured. Results. Before surgery, 6 of the 12 children showed normal VEMPs, 1 showed a decrease in the amplitude of VEMPs and five showed no VEMP response. After surgery, with the cochlear implant device off, 1 child showed a decreased VEMP and 11 showed no VEMPs. With the cochlear implant device on, four children showed VEMPs and eight did not. [ABSTRACT FROM AUTHOR]

The aim of this study was to investigate auditory cortex function in the context of auditory stimuli in a patient with auditory agnosia due to bilateral lesions confined to the auditory radiations. A male patient experienced mild left temporal hemiplegia because of right putaminal hemorrhage at the age of 43 years. Thereafter he recovered completely but hypertension persisted. When he was 53 years old, he suffered left putaminal hemorrhage and went into a coma. After recovering from the coma and right hemiplegia he could hear but could not discriminate speech sounds. Brain CT and MRI demonstrated small bilateral lesions confined to the auditory radiations. Magnetoencephalography demonstrated the disappearance of middle latency responses and auditory-evoked potential studies showed a very small Pa peak. In contrast, a positron emission tomography study demonstrated a marked increase in blood flow in the bilateral auditory cortex in response to both click and monosyllable stimuli. It is speculated that the auditory cortex receives functional projections from the cochlea via non-specific pathways in the cerebral hemispheres. [ABSTRACT FROM AUTHOR]

Hypoxia in adults frequently causes damage to the brain, but not the inner ear. However, hypoxia in neonates with inadequate blood–inner ear barrier function causes damage to the inner ear, leading to hearing loss and equilibration disorder. Clinically, asphyxiated neonates sometimes have the complication of sensorineural hearing impairment at high frequencies. Many reports suggest that this problem is caused by hypoxic encephalopathy. However, it is not clear whether inner ear disorders are present. In this report we examined the inner ear pathology of four asphyxiated neonates using serial sections of temporal bone. The subjects ( n =4) were 1–13-day-old neonates with pregnancy periods of 24–36 weeks. Their fetal growth curves were within the normal range. There was one case each of twin pregnancy, placental abruption, placenta previa and meconium aspiration syndrome. For the case of severe neonatal asphyxia, damage to the inner ear included the degeneration and disappearance of outer hair cells of the organ of Corti and edematous changes in the stria vascularis. Degeneration of spiral ganglion and vestibular ganglion cells was observed in two of the other cases. [ABSTRACT FROM AUTHOR]

Three young adult males with Pelizaeus–Merzbacher disease have been followed up since childhood. This disease is thought to be a dysmyelinating disorder of the brain during the prenatal period caused by gene mutations. The patients manifested horizontal nystagmus and severe rigidity of the extremities. Although the patients showed only waves I and II in auditory brainstem responses, they had relatively good hearing ability at ≈30&ThickSpace;dB. They could not speak words at all but could hear well and enjoy listening to conversation and music. One of them had a normal hearing threshold in pure-tone audiometry and a normal speech discrimination rate in speech audiometry. This can be explained by a nerve conduction blockade through dysmyelinated axons or the desynchronization of neurons and nerves responsible for the waves following waves I and II. At present, all three patients are living with their families. We report their present hearing, speech and language abilities. [ABSTRACT FROM AUTHOR]

Conclusions . In a patient with bilateral auditory neuropathy (AN), the vestibular-evoked myogenic potential (VEMP) was probably absent because of a neuropathy involving the inferior vestibular nerve and/or its end organ, the saccule. Our result can therefore be interpreted as a concomitant unilateral sacculo-collic neuropathy. We suggest the use of more precise terms to characterize AN patients with involvement of different parts of the inner ear and its innervations. We encourage detailed vestibular assessment in patients with AN in order to assess the co-existence of any symptomatic or asymptomatic vestibular disorder. Information such as that provided in this report will be valuable for clinicians caring for this group of patients. Objective . AN is a disorder characterized by the absence or severe impairment of auditory brainstem responses in the presence of normal cochlear outer hair cell function as revealed by otoacoustic emissions (OAEs) and/or electrocochleography (ECoG). A variety of processes and etiologies are thought to be involved in its pathophysiology. In most literature reports the auditory profile of patients with AN is discussed. However, the extent of vestibular involvement, especially that involving the saccule, is not known. We performed vestibular tests to assess the status of the saccule in a patient with AN. Material and methods . One patient with AN was studied. The patient was a right-handed 21-year-old female with chief complaints of hearing loss and speech perception difficulty. Results . The auditory test results were consistent with the diagnosis of AN, i.e. absent auditory brainstem responses, moderate hearing loss, an inappropriately profound speech discrimination score and the presence of OAEs and measurable cochlear microphonics on ECoG. On neurological examination, gait and balance tests were normal. Ice-water caloric testing induced a sensation of dizziness in both ears. Short tone-burst VEMPs showed no response on left-ear stimulation and a biphasic response with normal latency and amplitude on right-ear stimulation. [ABSTRACT FROM AUTHOR]

Hearing loss and equilibrium dysfunction have different etiologies in patients with large vestibular aqueduct syndrome. We suggest that all children with distal renal tubular acidosis (dRTA) should be subjected to an equilibrium study and audiological evaluation, as well as to a CT or MRI scan. dRTA has been described in association with sensorineural hearing loss, but there are no reported cases that have been examined in detail using audiological and equilibrium studies. We report here a case of progressive sensorineural hearing loss with a large vestibular aqueduct and dRTA, and the results of audiological and equilibrium studies. A 31-year-old female presented with hearing loss, tinnitus and vertigo. She had been treated with oral sodium citrate, potassium citrate and potassium chloride supplementation because of dRTA since the age of 1 month. The pure-tone audiogram of the patient was off the scale for the right ear and showed progressive sensorineural hearing loss for the left ear. Ice-water caloric testing showed canal paresis on the left side. Temporal bone CT and inner ear MRI revealed a large vestibular aqueduct and a large endolymphatic sac on both sides. [ABSTRACT FROM AUTHOR]

Conclusion These results suggest that COX-2 and bcl-2 protein were overexpressed and that apoptosis was reduced in MEC compared to PMA, and that COX-2 may regulate the degree of apoptosis by modulating bcl-2 protein in PMA and MEC. Objective Cyclooxygenase (COX)-2 plays a crucial role in tumorigenesis and overexpression of COX-2 in vitro accompanied by overexpression of bcl-2 protein has been shown to reduce apoptosis. The purpose of this study was to verify that COX-2 regulates the degree of apoptosis by modulating bcl-2 protein in benign and malignant parotid gland tumors. Material and methods We examined archival formalin-fixed, paraffin-embedded tissue sections of 10 pleomorphic adenomas (PMAs) and 10 mucoepidermoid carcinomas (MECs) by immunostaining with anti-COX-2, anti-bcl-2 and anti-single-stranded DNA (ssDNA) antibodies. Labeling indices of the three antibodies were calculated using computer-assisted image analysis. Results Labeling indices (mean&PlusMinus;SD) of anti-COX-2 antibody in PMA and MEC were 2.05&PlusMinus;1.30 and 11.2&PlusMinus;2.95, respectively ( p <0.001), those of anti-bcl-2 antibody were 2.00&PlusMinus;1.28 and 9.68&PlusMinus;4.05, respectively ( p <0.001) and those of anti-ssDNA antibody were 8.06&PlusMinus;2.54 and 2.08&PlusMinus;1.47, respectively ( p <0.001). Correlation coefficients between the labeling indices of anti-COX-2 antibody and anti-bcl-2 antibody, anti-bcl-2 antibody and anti-ssDNA antibody and anti-COX-2 antibody and anti-ssDNA antibody were 0.88, -0.75 and -0.76, respectively ( p <0.001). [ABSTRACT FROM AUTHOR]

In a previous study we showed that, in rat spiral ganglion neurons (SGNs), the adenosine 5'-triphosphate (ATP)-evoked currents were a combination of the activation of ionotropic receptors (the first fast current) and the activation of metabotropic receptors which secondarily opened non-selective cation channels. These two conductances imply the involvement of different receptor subtypes. In the present study, we tested three subtype-specific purinergic ligands: α,β-methylene ATP (α,β-meATP) for P2X receptors, uridine 5′-triphosphate (UTP) for P2Y receptors and 2′-3′-O-(4-benzoylbenzoyl) ATP (Bz-ATP) for P2Z (P2X 7 ) receptors. Application of 100 μM α,β-meATP did not trigger any significant change in membrane conductance, while the SGNs were responsive to ATP. Pressure application of UTP (100 μM, 1 s) evoked an inward current averaging 344±169 pA at a holding potential of -50 mV. The conductance developed after a latency averaging 1.5±0.6 s, took 4-6 s to peak and reversed slowly within 15-30 s. The current-voltage curve reversed near 0 mV, suggesting a non-selective cation conductance, like the second component of the ATP conductance. Bz-ATP evoked an inward current which developed without latency, was sustained during ligand application and was rapidly inactivated at the end of application: the same characteristics as the first component of the ATP-evoked current. The Bz-ATP conductance reversed around -10 mV, indicating also a non-selective cation conductance. These results suggest that, in SGNs, ATP acts via two different receptor subtypes, ionotropic P2Z receptors and metabotropic P2Y receptors, and that these two receptor subtypes can assume different physiological roles. [ABSTRACT FROM AUTHOR]