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Clinical & Experimental Optometry Mar 2011
Topics: Child; Deafness; Humans; Hypopigmentation; Iris Diseases; Male; Pigmentation Disorders; Waardenburg Syndrome
PubMed: 21352370
DOI: 10.1111/j.1444-0938.2010.00533.x -
Anais Brasileiros de Dermatologia 2015Waardenburg syndrome is an inherited disease characterized by sensorineural hearing loss, pigmentation changes and minor facial malformations. It has four clinical...
Waardenburg syndrome is an inherited disease characterized by sensorineural hearing loss, pigmentation changes and minor facial malformations. It has four clinical variants. We report the case of a girl who, like her mother, was affected by this syndrome. The diagnosis was made after detection and treatment of deafness.
Topics: Child; Deafness; Early Diagnosis; Female; Humans; Phenotype; Waardenburg Syndrome
PubMed: 26375234
DOI: 10.1590/abd1806-4841.20153343 -
Hearing Research Nov 2011Although the cochlear implant is already the world's most successful neural prosthesis, opportunities for further improvement abound. Promising areas of current research... (Review)
Review
Although the cochlear implant is already the world's most successful neural prosthesis, opportunities for further improvement abound. Promising areas of current research include work on improving the biological infrastructure in the implanted cochlea to optimize reception of cochlear implant stimulation and on designing the pattern of electrical stimulation to take maximal advantage of conditions in the implanted cochlea. In this review we summarize what is currently known about conditions in the cochlea of deaf, implanted humans and then review recent work from our animal laboratory investigating the effects of preserving or reinnervating tissues on psychophysical and electrophysiological measures of implant function. Additionally we review work from our human laboratory on optimizing the pattern of electrical stimulation to better utilize strengths in the cochlear infrastructure. Histological studies of human temporal bones from implant users and from people who would have been candidates for implants show a range of pathologic conditions including spiral ganglion cell counts ranging from approximately 2% to 92% of normal and partial hair cell survival in some cases. To duplicate these conditions in a guinea pig model, we use a variety of deafening and implantation procedures as well as post-deafening therapies designed to protect neurons and/or regenerate neurites. Across populations of human patients, relationships between nerve survival and functional measures such as speech have been difficult to demonstrate, possibly due to the numerous subject variables that can affect implant function and the elapsed time between functional measures and postmortem histology. However, psychophysical studies across stimulation sites within individual human subjects suggest that biological conditions near the implanted electrodes contribute significantly to implant function, and this is supported by studies in animal models comparing histological findings to psychophysical and electrophysiological data. Results of these studies support the efforts to improve the biological infrastructure in the implanted ear and guide strategies which optimize stimulation patterns to match patient-specific conditions in the cochlea.
Topics: Acoustic Stimulation; Animals; Cochlea; Cochlear Implantation; Cochlear Implants; Correction of Hearing Impairment; Deafness; Electric Stimulation; Humans; Models, Animal; Nerve Regeneration; Persons With Hearing Impairments; Prosthesis Design; Signal Processing, Computer-Assisted
PubMed: 21605648
DOI: 10.1016/j.heares.2011.05.002 -
EMBO Molecular Medicine Apr 2024Approximately half a billion people—5% of the world’s population—suffer from disabling hearing impairment (HI) according to the WHO...
Approximately half a billion people—5% of the world’s population—suffer from disabling hearing impairment (HI) according to the WHO (http://www.who.int/features/factfiles/deafness/en/). HI commonly hampers speech acquisition, leads to social isolation and increases risk for depression and cognitive decline. One to two per thousand children are born with disabling HI and over 50% of sensorineural HI is caused by defects in individual genes (deafness genes) of which roughly 150 have been identified so far (http://hereditaryhearingloss.org/). In case of profound hearing impairment or deafness, cochlear implants that bypass the dysfunctional or lost sensory hair cells and electrically stimulate the auditory nerve partially restore hearing. However, hearing with cochlear implants has shortcomings such as limited understanding of speech in background noise. So, there remains a major unmet medical need for improved hearing restoration (Wolf et al, 2022). Yet, despite major research efforts, a causal treatment based on pharmacology, gene therapy, or stem cells had, so far, not been clinically available. Now, this is finally changing at least for some patients: first in human trials prove the concept for inner ear gene therapy of otoferlin-related synaptic deafness.
Topics: Humans; Deafness; Genetic Therapy
PubMed: 38528140
DOI: 10.1038/s44321-024-00058-6 -
Bulletin of the World Health... Oct 2019The lack of an appropriately trained global hearing-care workforce is recognized as a barrier to developing and implementing services to treat ear and hearing disorders....
The lack of an appropriately trained global hearing-care workforce is recognized as a barrier to developing and implementing services to treat ear and hearing disorders. In this article we examine some of the published literature on the current global workforce for ear and hearing care. We outline the status of both the primary-care workforce, including community health workers, and specialist services, including audiologists, ear, nose and throat specialists, speech and language therapists, and teachers of the deaf. We discuss models of training health workers in ear and hearing care, including the role of task-sharing and the challenges of training in low and middle-income countries. We structure the article by the components of ear and hearing care that may be delivered in isolation or in integrated models of care: primary care assessment and intervention; screening; hearing tests; hearing rehabilitation; middle-ear surgery; deaf services; and cochlear implant programmes. We highlight important knowledge gaps and areas for future research and reporting.
Topics: Community Health Workers; Deafness; Health Personnel; Hearing; Hearing Loss; Hearing Tests; Humans; Primary Health Care
PubMed: 31656334
DOI: 10.2471/BLT.18.224659 -
Tidsskrift For Den Norske Laegeforening... Oct 2012
Topics: Deafness; Humans; Persons With Hearing Impairments; Social Identification
PubMed: 23038180
DOI: 10.4045/tidsskr.12.0988 -
Cellular and Molecular Life Sciences :... Feb 2020Estrogen is the major female hormone involved in reproductive functions, but it also exerts a variety of additional roles in non-reproductive organs. In this review, we... (Review)
Review
Estrogen is the major female hormone involved in reproductive functions, but it also exerts a variety of additional roles in non-reproductive organs. In this review, we highlight the preclinical and clinical studies that have pointed out sex differences and estrogenic influence on audition. We also describe the experimental evidences supporting a protective role of estrogen towards acquired forms of hearing loss. Although a high level of endogenous estrogen is associated with a better hearing function, hormonal treatments at menopause have provided contradictory outcomes. The various factors that are likely to explain these discrepancies include the treatment regimen as well as the hormonal status and responsiveness of the patients. The complexity of estrogen signaling is being untangled and many downstream effectors of its genomic and non-genomic actions have been identified in other systems. Based on these advances and on the common physio-pathological events that underlie age-related, drug or noise-induced hearing loss, we discuss potential mechanisms for their protective actions in the cochlea.
Topics: Animals; Cochlea; Deafness; Estrogens; Female; Hearing; Humans; Male; Receptors, Estrogen; Sex Characteristics; Sex Factors; Signal Transduction
PubMed: 31522250
DOI: 10.1007/s00018-019-03295-y -
Otology & Neurotology : Official... Dec 2016Considerable unexplained variability and large individual differences exist in speech recognition outcomes for postlingually deaf adults who use cochlear implants (CIs),... (Review)
Review
OBJECTIVE
Considerable unexplained variability and large individual differences exist in speech recognition outcomes for postlingually deaf adults who use cochlear implants (CIs), and a sizeable fraction of CI users can be considered "poor performers." This article summarizes our current knowledge of poor CI performance, and provides suggestions to clinicians managing these patients.
METHOD
Studies are reviewed pertaining to speech recognition variability in adults with hearing loss. Findings are augmented by recent studies in our laboratories examining outcomes in postlingually deaf adults with CIs.
RESULTS
In addition to conventional clinical predictors of CI performance (e.g., amount of residual hearing, duration of deafness), factors pertaining to both "bottom-up" auditory sensitivity to the spectro-temporal details of speech, and "top-down" linguistic knowledge and neurocognitive functions contribute to CI outcomes.
CONCLUSIONS
The broad array of factors that contribute to speech recognition performance in adult CI users suggests the potential both for novel diagnostic assessment batteries to explain poor performance, and also new rehabilitation strategies for patients who exhibit poor outcomes. Moreover, this broad array of factors determining outcome performance suggests the need to treat individual CI patients using a personalized rehabilitation approach.
Topics: Adult; Cochlear Implantation; Cochlear Implants; Deafness; Humans; Persons With Hearing Impairments; Speech Perception
PubMed: 27631833
DOI: 10.1097/MAO.0000000000001211 -
The Lancet. Neurology May 2016Progress in biomedical technology (cochlear, vestibular, and retinal implants) has led to remarkable success in neurosensory restoration, particularly in the auditory... (Review)
Review
Progress in biomedical technology (cochlear, vestibular, and retinal implants) has led to remarkable success in neurosensory restoration, particularly in the auditory system. However, outcomes vary considerably, even after accounting for comorbidity-for example, after cochlear implantation, some deaf children develop spoken language skills approaching those of their hearing peers, whereas other children fail to do so. Here, we review evidence that auditory deprivation has widespread effects on brain development, affecting the capacity to process information beyond the auditory system. After sensory loss and deafness, the brain's effective connectivity is altered within the auditory system, between sensory systems, and between the auditory system and centres serving higher order neurocognitive functions. As a result, congenital sensory loss could be thought of as a connectome disease, with interindividual variability in the brain's adaptation to sensory loss underpinning much of the observed variation in outcome of cochlear implantation. Different executive functions, sequential processing, and concept formation are at particular risk in deaf children. A battery of clinical tests can allow early identification of neurocognitive risk factors. Intervention strategies that address these impairments with a personalised approach, taking interindividual variations into account, will further improve outcomes.
Topics: Brain; Child; Concept Formation; Connectome; Deafness; Developmental Disabilities; Executive Function; Humans
PubMed: 26976647
DOI: 10.1016/S1474-4422(16)00034-X -
International Journal of Pediatric... Mar 2019To assist medical and hearing-science professionals in supporting parents of deaf children, we have identified common questions that parents may have and provide... (Review)
Review
To assist medical and hearing-science professionals in supporting parents of deaf children, we have identified common questions that parents may have and provide evidence-based answers. In doing so, a compassionate and positive narrative about deafness and deaf children is offered, one that relies on recent research evidence regarding the critical nature of early exposure to a fully accessible visual language, which in the United States is American Sign Language (ASL). This evidence includes the role of sign language in language acquisition, cognitive development, and literacy. In order for parents to provide a nurturing and anxiety-free environment for early childhood development, signing at home is important even if their child also has the additional nurturing and care of a signing community. It is not just the early years of a child's life that matter for language acquisition; it's the early months, the early weeks, even the early days. Deaf children cannot wait for accessible language input. The whole family must learn simultaneously as the deaf child learns. Even moderate fluency on the part of the family benefits the child enormously. And learning the sign language together can be one of the strongest bonding experiences that the family and deaf child have.
Topics: Child; Child Development; Child, Preschool; Deafness; Evidence-Based Medicine; Humans; Language Development; Literacy; Parents; Sign Language
PubMed: 30623850
DOI: 10.1016/j.ijporl.2018.12.036