The age of diagnosis of sensorineural hearing impairment in children

Objective: To identify factors responsible for delays in diagnosis and treatment of pediatric sensorineural hearing impairment (SNHI), and to assess the thoroughness of medical evaluation in these children. Design: Retrospective analysis. Setting: State-supported school for the deaf. Patients and other participants: 291 children with SNHI, the vast majority of whom are profoundly hearing impaired. Data were collected from the school's database, individual student records, and a parental questionnaire. Main outcome measures: (1) The age of diagnosis and treatment of SNHI; (2) factors leading to a delay in diagnosis; (3) current medical evaluations used to determine the etiology of SNHI; and (4) the level of parental satisfaction with the evaluation process. Results: Many children with SNHI experience delays in diagnosis from the time of first suspicion of hearing loss. Children with a risk factor for SNHI are diagnosed no earlier than children without a risk factor. Caucasian children are diagnosed significantly earlier than either Black or Hispanic children, regardless of socioeconomic status. Inconsistent medical evaluation ensues following the diagnosis of SNHI, and parental satisfaction with this process is low. Conclusions: The average age of diagnosis of SNHI remains unacceptably high. There exists a need to enhance physician awareness of childhood deafness and to develop guidelines for the medical evaluation in cases of pediatric SNHI. Lastly, the importance of parental concern regarding a child's hearing or language development must be re-emphasized.     

Simulation of sensorineural hearing impairment

A hearing loss simulation system (HELOS) was designed and constructed to simulate various aspects of sensorineural hearing impairment. The theoretical bases for HELOS were several threshold and suprathreshold auditory phenomena typically exhibited by people with sensorineural hearing losses. In addition to providing differential attenuation of acoustic signals across the frequency range, HELOS simulated loudness recruitment, loudness discomfort thresholds, reduced dynamic range, and reduced frequency selectivity. Three basic audiometric configurations were chosen to investigate the effects of the aforementioned components of a sensorineural hearing impairment on the auditory perception of speech. They were: (1) a sloping high-frequency hearing loss; (2) a flat, severe hearing loss; (3) a severe/profound hearing loss. The battery of tests administered to a group of normal-hearing adults consisted of pure-tone audiometry and PB-word recognition tests, as well as vowel and consonant identification tests. For comparable audiometric configurations, the results from the speech-perception tests were in good agreement with the published results of similar tests administered to persons with sensorineural hearing losses.     

Pitch vulnerability in sensorineural hearing impairment

Listeners with cochlear impairment were studied in an ABX pitch-matching paradigm. These listeners showed excellent ability to adjust one sinusoid (X) to match the frequency of another (B), except when a leading tone (A) was present. Pitch shifts induced by the leading tone exaggerate the pitch contrast between tones A and B, even in normal-hearing listeners, but the effect in sensorineural listeners is several times larger and indicates a severe vulnerability of pitch. The degree of pitch distortion does not appear to bear any simple relationship to the degree of hearing loss, or to stimulus amplitudes. The effect is obtained at 'comfortable' listening levels. Vulnerability of pitch, rather than a failure in discriminative capacity, may underlie some of the qualitative perceptual difficulties found in sensorineural hearing impairment.     

Pathology of vascular sensorineural hearing impairment

Circulatory disorders, which are well documented in most parts of the human body, are not well documented in the inner ear, although they are expected to occur. It has been previously shown that experimental occlusion of the labyrinthine artery in animals results in severe degenerative changes, fibrosis, and new bone formation in the cochlea. Accordingly, this paper presents presumptive evidence that depriving the human cochlea of its blood supply after surgical removal of an acoustic tumor results in severe degenerative changes that progress to total ossification of the cochlear spaces. This paper also discusses similar changes seen in temporal bones of two patients with sudden sensorineural hearing impairment. Based on these observations, the author concludes that occlusive arterial disease, whether thrombotic, embolic, or spastic, plays a role in some sudden sensorineural hearing losses. Cochlea ossification, detected by polytomography, suggests a vascular etiology of the hearing impairment. Treatment with vasodilator drugs and anticoagulants is justified in these cases until a better diagnostic protocol is developed to eliminate other causes.     

Auditory deprivation in adults with asymmetric, sensorineural hearing impairment

The purpose of this investigation was to prospectively examine performance on the pure-tone air-conduction threshold, speech-recognition threshold, and suprathreshold word-recognition tests over time in 21 monaurally aided (experimental group) and 28 unaided adults (control group) with asymmetric, sensorineural hearing impairment. The results revealed significant declines on the mean suprathreshold word-recognition scores over time at one and two years post-baseline for the worse ears of the control participants; no declines occurred in the worse ears of the experimental participants or in the better ears of either group. A slight, significant increase in the pure-tone average occurred for the better ears of both groups. The findings are consistent with the presence of an auditory deprivation effect on suprathreshold word-recognition ability in the control group, suggesting that lack of amplification leads to decline in word-recognition performance over time in the worse ears of adults with asymmetric sensorineural hearing impairment.     

Autosomal recessive sensorineural hearing impairment, dizziness, and hypodontia

A previously undescribed syndrome with profound sensorineural hearing loss since early infancy, episodes of dizziness, and hypodontia developed in a brother and sister. The presence of two unaffected children and unaffected parents suggests autosomal recessive inheritance.     

The large vestibular aqueduct syndrome and sensorineural hearing loss in the pediatric population

Sensorineural hearing loss, associated with a dilated vestibular aqueduct, is often described as progressive. Since 1982, computed tomography of the mastoids has become part of the routine investigation of deaf children at Sainte-Justine Hospital. Using clinical, audiometric and radiological material from 130 patients with sensorineural hearing loss, we identified 18 patients with enlarged vestibular aqueducts. The large vestibular aqueduct population was then compared to the normal vestibular aqueduct patients in regard to the degree and evolution of the sensorineural hearing loss. Progression of hearing loss was noted in 46% of patients in the presence of large vestibular aqueducts as compared to 35% in the absence of this anomaly. Normal radiographic findings did not exclude the possibility of further hearing loss.     

Progressive sensorineural hearing impairment in professional fishery divers

There have been many reports of a high rate of hearing impairment in divers. A prospective study was performed to determine whether sensorineural hearing acuity in the same divers deteriorated faster than in a normal population as they continued diving. After an observation period of approximately 5 years, audiometric examination was performed on a group of professional fishery divers who had normal hearing or sensorineural hearing loss at the time of initial study. Thirty-three ears of 18 divers were included in statistical analyses. The average hearing deterioration in the divers in 5 years, after elimination of the aging effect, was 6.6 dB (SD 4.5) and was statistically significant. We concluded that the hearing acuity of our subjects deteriorated faster than that of normal Japanese.     

Reversible sensorineural hearing impairment induced by a carotid body tumor

A case of a 62-year-old Austrian man having a 25-year history of a right-sided carotid body tumor (CBT) is presented. Three months before being transferred to the University of Vienna for tumor resection the patient developed symptoms of tinnitus, progressive ipsilateral hearing loss and dysphagia. Pure-tone audiometry demonstrated a 50 dB right sensorineural hearing loss. A 6 × 6 × 4 cm firm, pulsatile mass was found in the right carotid triangle and extending towards the base of the skull. One week after radical tumor resection all preoperative symptoms disappeared and hearing of the right ear recovered. Review of the available literature showed that hearing loss and tinnitus are unusual symptoms of a CBT. Our findings suggest that routine audiometric evaluations in such cases of CBT patients should be obtained in order to determine the real incidence of audiological disorders. Received: 17 October 1997 / Accepted: 19 May 1998     

Multicenter audiometric results with the Vibrant Soundbridge, a semi-implantable hearing device for sensorineural hearing impairment

The Vibrant Soundbridge, a semi-implantable hearing device for subjects with moderate to severe sensorineural hearing impairment was introduced commercially. First audiologic results are presented on 63 patients from 10 European implant centers. Hearing loss was at 0.5, 1, 2, and 4 kHz varying between 43 and 81 dB HL. The patients used the analogue audio processor, type 302. Measured sound-field gain was compared with NAL-R target values. For most patients an acceptable agreement was found. There was a subgroup of patients, however, with relatively low gain. The results suggest that this was related to the suboptimal positioning and fixation of the transducer to the incus.     

Steroid-responsive bilateral sensorineural hearing loss and immune complexes

Summary We have recognized in recent years that some cases with idiopathic bilateral sensorineural hearing loss which showed acute progression in either ear responded to steroid and that the improved hearing level could be maintained by longterm administeration of steroid only.Forty cases of bilateral sensorineural hearing loss were selected for study. In most of these cases hearing deterioration of either ear was confirmed by audiometry.Eight of fifteen cases with marked improvement have been proved to respond to steroid treatment. These eight cases include three cases with syphilitic deafness and one case with aortitis syndrome. In four other cases the causes are still unknown, but could be due to autoimmune mechanisms. In four of 25 cases the immune complexes (IC) value was higher than normal and three among them responded to steroid.Since a high IC value has been reported in lupus nephritis, immunologic examinations are necessary for patients over 30 years of age with bilateral sensorineural hearing loss.     

Prognostic factors for vestibular impairment in sensorineural hearing loss

The clinical course and prognosis in sensorineural hearing loss (SNHL) may be even worse if vestibular system is also involved, especially due to near location of anatomical structures in the inner ear. The aim of the study was to determine prognostic value of some clinical, audiological and demographic factors associated with SNHL in predicting a possibility of vestibular impairment. The study was conducted on 124 consecutive patients (183 ears) diagnosed for sensorineural hearing loss during 1 year in our department. In all of them, audiological (pure-tone, speech and impedance audiometry, ABR) and ENG examinations (visual ocular–motor, positional, kinetic and caloric tests) were performed. The correlations between ENG outcome and the following variables associated with sensorineural hearing loss were investigated: audiological (degree and location of hearing loss, audiogram configuration), clinical (tinnitus, vertigo, dizziness) and demographic (age, sex) factors. Normal ENG was recorded in 26.6%, vestibular impairment of peripheral type in 38.7%, and central type in 34.7% of the patients. In a multivariate stepwise linear regression analysis, the degree of hearing loss was the main variable correlating with abnormal ENG result. Tinnitus and location of hearing loss were also found to be the two other variables which, to some minor extent, can influence the ENG outcome. Peripheral vestibular impairment was observed more frequently in patients with residual hearing/deafness. The degree of hearing loss, presence of tinnitus and location of hearing loss are factors predicting the possibility of abnormal ENG outcome in sensorineural hearing loss.     

Audiometric, clinical and educational outcomes in a pediatric symptomatic congenital cytomegalovirus (CMV) population with sensorineural hearing loss

OBJECTIVE: To correlate audiometric findings and outcomes with the clinical, radiological and educational findings in a symptomatic congenital cytomegalovirus (CMV) population with sensorineural hearing loss. METHODS: A retrospective review of data from 21 symptomatic congenital CMV patients identified in a pediatric hearing impaired database of 1500 patients. Clinical data, audiometric thresholds and outcomes, radiographic abnormalities, communication and educational achievements were used as outcome measures. RESULTS: Twenty-one patients were identified with symptomatic congenital CMV infection at birth; 5 with unilateral hearing loss and 16 with bilateral hearing loss. The median initial pure-tone average (PTA) for the 21 subjects was 86 dB and the median final PTA was 100 dB. Progression of hearing loss was seen in 9 patients (43%). Neurological and radiological sequelae of symptomatic CMV infection were seen in 81% of affected patients. Children with neurological dysfunction were significantly more likely to rely on special education (p = 0.045). There was a significant correlation between the severity of the initial PTA and the development of a progressive hearing loss (p = 0.0058). Initial hearing thresholds were significantly better in those children with a history of jaundice (p = 0.002), hepatosplenomegaly (HSM) (p = 0.022) and cerebral palsy (CP) (p = 0.013). There was a significant correlation between a less severe final PTA and the presence of CP (p = 0.005). A history of mental retardation in children was significantly associated with poorer communication skills (p = 0.043). CONCLUSIONS: The severity of neurological manifestations in congenital symptomatic CMV infection was positively correlated with the need for total and manual communication and the reliance on special education. Statistical associations between clinical findings such as hepatic dysfunction, CP and hearing level were identified however plausible mechanisms explaining these associations remain ambiguous and are discussed in the context of this complex population of children with congenital symptomatic CMV.     

Progression of sensorineural hearing impairment in aided and unaided ears

The possibility of "adult onset auditory deprivation" has been proposed as a condition of extensive deterioration of speech discrimination in unaided ears. Pure tone thresholds and speech discrimination were studied in a follow-up examination on 500 patients using hearing aids unilaterally. The follow-up time ranged from 5 to 24 years. In average the same amount of deterioration was obtained in both ears. Deterioration in pure tone thresholds increased after the age of 80 years and speech discrimination after 65 years respectively. The results obtained gave no support to the concept of adult onset auditory deprivation in unaided ears.     

Otoacoustic emission-based hearing screening of a Greek NICU population

The pressing need for early identification of hearing-disabled children has led to the development of several neonatal hearing screening programmes world-wide. Today otoacoustic emissions represent a widely used methodology for identification of neonatal hearing impairment. The purpose of the present study is to determine the sensitivity and specificity of click-evoked otoacoustic emissions (cEOAEs) in a Greek NICU population and compare the cEOAE data to the final hearing status of these children. A total of 438 ears of 223 neonates at high risk for hearing impairment were tested with both brainstem response audiometry (ABR) and cEOAEs. In 107 neonates the final hearing status was determined by using behavioural and playtone audiometry, at an age greater than 2 1/2 years. The sensitivity and specificity of the cEOAEs were found to be 90 and 92.4% when compared to ABR results and 90.9 and 91.1% when compared to the children's hearing status, respectively. Click-EOAEs have been proved to be highly effective in determining whether or not hearing impairment really exists. Since conventional ABR does not meet the requirements for large scale screening programmes, the cEOAEs represent a reliable alternative.