André Goedegebure

Risk factors for sensorineural hearing loss in NICU infants compared to normal hearing NICU controls

OBJECTIVES To evaluate independent etiologic factors associated with sensorineural hearing loss in infants who have been admitted to the neonatal intensive care unit compared to normal hearing controls. METHOD Between 2004 and 2009, 3366 infants were admitted to the neonatal intensive care unit of Sophia Childrens Hospital, of which 3316 were screened with AABR. A total of 103 infants were referred for auditory brainstem response analysis after failure on neonatal hearing screening. We included all infants diagnosed with sensorineural hearing loss. Each patient was matched with two normal hearing controls from the neonatal intensive care unit of the same gender and postconceptional age. The following risk factors were studied: birth weight, dysmorphic features, APGAR scores (at 1, 5 and 10 min), respiratory distress (IRDS), CMV infection, sepsis, meningitis, cerebral bleeding, cerebral infarction, hyperbilirubinemia requiring phototherapy, peak total bilirubin level, furosemide, dexamethason, vancomycin, gentamycin and tobramycin administration. RESULTS Fifty-eight infants were diagnosed with sensorineural hearing loss: 26 girls and 32 boys. The incidence of dysmorphic features (P=0.000), low APGAR score (1 min) (P=0.01), sepsis (P=0.003), meningitis (P=0.013), cerebral bleeding (P=0.016) and cerebral infarction (P=0.000) were significantly increased in infants with sensorineural hearing loss compared to normal hearing controls (n=116). CONCLUSION Dysmorphic features, low APGAR scores at 1 min, sepsis, meningitis, cerebral bleeding and cerebral infarction are associated with sensorineural hearing loss independent of neonatal intensive care unit admittance.

Hearing loss in Pompe disease revisited: results from a study of 24 children

Little information is available regarding the auditory function in Pompe patients. Hearing loss has been reported in classic infantile patients, but it is still unknown whether central nervous system involvement interferes with auditory function and whether enzyme replacement therapy can improve hearing. Auditory function has not been studied in children with milder forms of the disease. We analyzed repetitive auditory brainstem response measurements and pure tone audiometry in 24 children with Pompe disease. Only 1 of 13 patients with milder phenotypes showed recurrent conductive hearing loss, while 10 out of 11 classic infantile patients had sensorineural hearing defects. These patients also had a high prevalence of conductive hearing loss. Five patients showed evidence of mild retrocochlear pathology, suggestive of glycogen accumulation in the central nervous system. Hearing loss persisted during therapy in all patients. The results emphasize the need for careful monitoring of auditory function in classic infantile Pompe patients, and for early implementation of hearing aids to protect speech and language development.

Prevalence of age-related hearing loss, including sex differences, in older adults in a large cohort study.

To obtain actual status of age‐related hearing loss in a general unscreened population of older Dutch adults and to investigate whether the prevalence or degree has changed over time.

Inventory of current EU paediatric vision and hearing screening programmes

Objective To examine the diversity in paediatric vision and hearing screening programmes in Europe. Methods Themes for comparison of screening programmes derived from literature were used to compile three questionnaires on vision, hearing, and public health screening. Tests used, professions involved, age, and frequency of testing seem to influence sensitivity, specificity, and costs most. Questionnaires were sent to ophthalmologists, orthoptists, otolaryngologists, and audiologists involved in paediatric screening in all EU full-member, candidate, and associate states. Answers were cross-checked. Results Thirty-nine countries participated; 35 have a vision screening programme, 33 a nation-wide neonatal hearing screening programme. Visual acuity (VA) is measured in 35 countries, in 71% of these more than once. First measurement of VA varies from three to seven years of age, but is usually before age five. At age three and four, picture charts, including Lea Hyvarinen, are used most; in children over four, Tumbling-E and Snellen. As first hearing screening test, otoacoustic emission is used most in healthy neonates, and auditory brainstem response in premature newborns. The majority of hearing testing programmes are staged; children are referred after 1–4 abnormal tests. Vision screening is performed mostly by paediatricians, ophthalmologists, or nurses. Funding is mostly by health insurance or state. Coverage was reported as >95% in half of countries, but reporting was often not first-hand. Conclusion Largest differences were found in VA charts used (12), professions involved in vision screening (10), number of hearing screening tests before referral (1–4), and funding sources (8).

Auditory brainstem response morphology and analysis in very preterm neonatal intensive care unit infants.

Analysis of auditory brainstem response (ABR) in very preterm infants can be difficult owing to the poor detectability of the various components of the ABR. We evaluated the ABR morphology and tried to extend the current assessment system.

An initial overestimation of sensorineural hearing loss in NICU infants after failure on neonatal hearing screening

OBJECTIVE Infants admitted to neonatal intensive care units have a higher incidence of significant congenital hearing loss. We classified audiologic diagnoses and follow-up in infants who had been admitted to our neonatal intensive care unit. METHODS We included all infants admitted to the neonatal intensive care unit at Sophia Childrens Hospital between 2004 and 2009 who had been referred for auditory brainstem response measurement after failing neonatal hearing screening with automated auditory brainstem response. We retrospectively analyzed the results of auditory brainstem response measurement. RESULTS Between 2004 and 2009 3316 infants admitted to our neonatal intensive care unit had neonatal hearing screening. 103 infants failed neonatal hearing screening: 46 girls and 57 boys. After first auditory brainstem response measurement we found 18% had normal hearing or a minimal hearing loss. The remainder had a type of hearing loss, distributed as follows: 15% conductive, 32% symmetric sensorineural, 14% asymmetric sensorineural, and 21% absent auditory brainstem responses. Repeated auditory brainstem response measurement showed a shift in hearing outcome. The main difference was an improvement from symmetric sensorineural hearing loss to normal hearing. However, in a small percentage of children, the hearing deteriorated. CONCLUSIONS As many as 58% of infants in this high-risk population who failed the neonatal hearing screening were diagnosed with sensorineural hearing loss or absent auditory brainstem responses. An initial overestimation of sensorineural hearing loss of about 10% was seen at first auditory brainstem response measurement. This may be partially explained by a conductive component that has resolved. Finally, in a small percentage of children the hearing deteriorated.

Risk factors for auditory neuropathy spectrum disorder in NICU infants compared to normal-hearing NICU controls.

To evaluate independent etiologic factors associated with auditory neuropathy spectrum disorder (ANSD) in infants who have been admitted to the neonatal intensive care unit (NICU) compared to normal‐hearing controls.

Application of Noise Reduction Algorithm ClearVoice in Cochlear Implant Processing: Effects on Noise Tolerance and Speech Intelligibility in Noise in Relation to Spectral Resolution

Objectives: Noise reduction algorithms have recently been introduced in the design of clinically available cochlear implants. This study was intended to (1) evaluate the effect of noise reduction algorithm “ClearVoice” on noise tolerance and on speech intelligibility in noisy conditions at different speech-in-noise ratios in cochlear implant users, and (2) test the hypothesis that CI recipients with low spectral resolution might benefit more from noise reduction algorithms than CI users with high spectral resolution. Design: A double-blind crossover design was used to measure the effect of the noise reduction algorithm ClearVoice on noise tolerance with the acceptable noise level (ANL) test and on speech in noise for three performance levels: speech reception thresholds (SRT) at 50%, 70%, and at a speech to noise ratio of SRT50% + 11 dB. Furthermore, they tested speech intelligibility in quiet. The effective spectral resolution was measured with a spectral-ripple discrimination test. Twenty users of the Advanced Bionics Harmony processor with HiRes120-processing participated in this study. Results: The noise reduction algorithm led to a significant improvement—a decrease of 3.6 dB—in the ANL test but had no significant effect on any of the three speech-in-noise performance levels. The improvement in ANL was not significantly correlated with any of the speech-in-noise measures, nor with the speech-in-noise ratio in the ANL test. However, higher maximum speech intelligibility in quiet conditions correlated significantly with higher noise tolerance. Spectral-ripple discrimination thresholds were not significantly correlated with the effect of noise reduction on ANL or on speech intelligibility in noise nor with the speech-in-noise ratios. The spectral-ripple discrimination thresholds did correlate significantly with maximum speech intelligibility in quiet but not with speech reception thresholds in noise. Conclusions: The noise reduction algorithm ClearVoice improves noise tolerance. However, this study shows no change in speech intelligibility in noise due to the algorithm. The improvement in noise tolerance is not significantly related to spectral-ripple discrimination thresholds, speech intelligibility measures, or signal to noise ratio. Our hypothesis that CI recipients with low spectral resolution have a greater benefit from noise reduction than CI users with high spectral resolution does not hold for noise tolerance or for speech intelligibility in noise.

Hearing impairment is associated with smaller brain volume in aging

Although recent studies show that age-related hearing impairment is associated with cerebral changes, data from a population perspective are still lacking. Therefore, we studied the relation between hearing impairment and brain volume in a large elderly cohort. From the population-based Rotterdam Study, 2,908 participants (mean age 65 years, 56% female) underwent a pure-tone audiogram to quantify hearing impairment. By performing MR imaging of the brain we quantified global and regional brain tissue volumes (total brain volume, gray matter volume, white matter (WM) volume, and lobe-specific volumes). We used multiple linear regression models, adjusting for age, sex, head size, time between hearing test and MR imaging, and relevant cognitive and cardiovascular covariates. Furthermore, we performed voxel-based morphometry to explore sub-regional differences. We found that a higher pure-tone threshold was associated with a smaller total brain volume [difference in standardized brain volume per decibel increase in hearing threshold in the age-sex adjusted model: -0.003 (95% confidence interval -0.004; -0.001)]. Specifically, WM volume was associated. Both associations were more pronounced in the lower frequencies. All associations were consistently present in all brain lobes in the lower frequencies and in most lobes in the higher frequencies, and were independent of cognitive function and cardiovascular risk factors. In voxel-based analyses we found associations of hearing impairment with smaller white volumes and some smaller and larger gray volumes, yet these were statistically non-significant. Our findings demonstrate that hearing impairment in elderly is related to smaller total brain volume, independent of cognition and cardiovascular risk factors. This mainly seems to be driven by smaller WM volume, throughout the brain.

Contributing Determinants to Hearing Loss in Elderly Men and Women: Results from the Population-Based Rotterdam Study

To contribute to a better understanding of the etiology in age-related hearing loss, we carried out a cross-sectional study of 3,315 participants (aged 52-99 years) in the Rotterdam Study, to analyze both low- and high-frequency hearing loss in men and women. Hearing thresholds with pure-tone audiometry were obtained, and other detailed information on a large number of possible determinants was collected. Hearing loss was associated with age, education, systolic blood pressure, diabetes mellitus, body mass index, smoking and alcohol consumption (inverse correlation). Remarkably, different associations were found for low- and high-frequency loss, as well as between men and women, suggesting that different mechanisms are involved in the etiology of age-related hearing loss.