|
|
| (33 intermediate revisions by 4 users not shown) |
| Line 1: |
Line 1: |
| | __NOTOC__ |
| {{Infobox_Disease | | | {{Infobox_Disease | |
| Name = {{PAGENAME}} | | | Name = {{PAGENAME}} | |
| Image = International Symbol for Deafness.svg | | | Image = International Symbol for Deafness.svg | |
| Caption = The International Symbol for Deafness | | | Caption = The International Symbol for Deafness | |
| DiseasesDB = 19942 |
| |
| ICD10 = {{ICD10|H|90||h|90}}-{{ICD10|H|91||h|90}} |
| |
| ICD9 = {{ICD9|389}} |
| |
| ICDO = |
| |
| OMIM = |
| |
| MedlinePlus = |
| |
| eMedicineSubj = |
| |
| eMedicineTopic = |
| |
| MeshID = D034381 |
| |
| }} | | }} |
| | '''For patient information click [[{{PAGENAME}} (patient information)|here]]''' |
| {{Hearing impairment}} | | {{Hearing impairment}} |
| {{AB}}
| |
|
| |
|
| {{SK}} Hearing loss | | {{SK}} Hearing impairment, deafness, decreased hearing; loss of hearing |
|
| |
|
| ==Overview== | | ==[[Hearing impairment overview|Overview]]== |
|
| |
|
| A '''hearing impairment''' or '''hearing loss''' is a full or partial decrease in the ability to detect or understand sounds.<ref name="def1">{{cite web|url=http://www.oafccd.com/factshee/fact59.htm|title=Speech and Language Terms and Abbreviations|accessdate=2006-12-02}}</ref>
| | ==[[Hearing impairment historical perspective|Historical Perspective]]== |
| Caused by a wide range of biological and environmental factors, loss of hearing can happen to any organism that perceives sound.
| |
|
| |
|
| * Hearing loss is categorized as a '''conductive''' and '''sensorineural'''
| | ==[[Hearing impairment classification|Classification]]== |
| * '''Conductive''' hearing loss is caused by any process that prevents sound from reaching the inner ear.
| |
| * '''Sensorineural''' hearing loss is due to nerve-type loss in either the inner ear or the auditory nerve
| |
|
| |
|
| '''See also:'''
| |
|
| |
|
| [[Hearing loss with craniofacial syndromes]] | | ==[[Hearing impairment pathophysiology|Pathophysiology]]== |
|
| |
|
| [[Conductive hearing loss]] | | ==[[Hearing impairment causes|Causes]]== |
|
| |
|
| [[Sensorineural hearing loss]] | | ==[[Hearing impairment differential diagnosis|Differentiating Hearing Impairment from other Diseases]]== |
|
| |
|
| [[Central hearing loss]] | | ==[[Hearing impairment epidemiology and demographics|Epidemiology and Demographics]]== |
|
| |
|
| [[Profound hearing loss]] | | ==[[Hearing impairment risk factors|Risk Factors]]== |
|
| |
|
| [[Unilateral hearing loss]] | | ==[[Hearing impairment screening|Screening]]== |
|
| |
|
| [[Noise-induced hearing loss]] | | ==[[Hearing impairment natural history, complications and prognosis|Natural History, Complications and Prognosis]]== |
|
| |
|
| [[Congenital hearing loss]] | | ==[[Hearing impairment diagnosis|Diagnosis]]== |
| | [[Hearing impairment history and symptoms|History and Symptoms]] | [[Hearing impairment physical examination|Physical Examination]] | [[Hearing impairment laboratory findings|Laboratory Findings]] | [[Hearing impairment CT|CT]] | [[Hearing impairment MRI|MRI]] | [[Hearing impairment other imaging findings|Other Imaging Findings]] | [[Hearing impairment other diagnostic studies|Other Diagnostic Studies]] |
|
| |
|
| ==Diagnosis== | | ==Treatment== |
| ==Physical Examination==
| | [[Hearing impairment medical therapy|Medical Therapy]] | [[Hearing impairment surgery|Surgery]] | [[Hearing impairment primary prevention|Primary Prevention]] | [[Hearing impairment secondary prevention|Secondary Prevention]] | [[Hearing impairment cost-effectiveness of therapy|Cost-Effectiveness of Therapy]] | [[Hearing impairment social impact|Social Impact]] | [[Hearing impairment future or investigational therapies|Future or Investigational Therapies]] |
| * Weber's tuning fork testing
| |
| * Rinne's tuning fork testing
| |
|
| |
|
| ==Categories of hearing impairment== | | ==Case Studies== |
| Hearing loss is categorized by its severity and by the age of onset. Two persons with the same severity of hearing loss will experience it quite differently if it occurs early or late in life. Furthermore, a loss can occur on only one side (unilateral) or on both (bilateral). | | :[[Hearing impairment case study one|Case #1]] |
|
| |
|
| ===Types=== | | ==Related Chapters== |
| As discussed above, there are three major types of hearing loss: neural/sensorineural, conductive, or a combination of both. Treatment depends upon the type of hearing loss that is present.
| |
| | |
| ===Quantification of hearing loss===<!-- This section is linked from [[Cochlear implant]] -->
| |
| The '''severity of hearing loss''' is measured by the degree of loudness, as measured in [[decibel]]s, a sound must attain before being detected by an individual. Hearing loss may be ranked as mild, moderate, severe or profound. It is quite common for someone to have more than one degree of hearing loss (i.e. mild sloping to severe). The following list shows the rankings and their corresponding decibel ranges:
| |
| | |
| * Mild:
| |
| ** for adults: between 25 and 40 dB
| |
| ** for children: between 15 and 40 dB
| |
| * Moderate: between 41 and 55 dB
| |
| * Moderately severe: between 56 and 70 dB
| |
| * Severe: between 71 and 90 dB
| |
| * Profound: 90 dB or greater
| |
| | |
| The quietest sound you can hear at different frequencies is plotted on an audiogram to reflect your ability to hear at different frequencies. The range of normal human hearing (from the softest audible sound to the loudest comfortable sound) is so great that the audiogram must be plotted using a logarithmic scale. This large normal range, and the different amounts of hearing loss at different frequencies, make it virtually impossible to accurately describe the amount of hearing loss in simple terms such as percentages or the rankings above.
| |
| | |
| Measuring hearing loss in terms of a percentage is debatable in terms of effectiveness, and has been compared to measuring weight in inches. Though in specific legal situations, where decibels of loss are converted via a recognized legal formula, one can infer a standardized "percentage of hearing loss" which is suitable for legal purposes only.
| |
| | |
| Another method for determining hearing loss, is the Hearing in Noise Test (HINT). HINT technology was developed by the [http://www.hei.org/ House Ear Institute], and is intended to measure an ability to understand speech in quiet and noisy environments. Unlike pure-tone tests, where only one ear is tested at a time, HINT evaluates hearing using both ears simultaneously (binaural), as binaural hearing is essential for communication in noisy environments, and for sound localization.
| |
| | |
| ===Age of onset of hearing impairment===
| |
| | |
| The age at which the hearing impairment develops is crucial to spoken language acquisition. Post-lingual hearing impairments are far more common than pre-lingual impairments.
| |
| | |
| If the hearing loss occurs at a young age, interference with the acquisition of [[spoken language]] and [[social skills]] may occur. [[Hearing aid]]s, which amplify the incoming sound, may alleviate some of the problems caused by hearing impairment, but are often insufficient. [[Cochlear implants]] artificially stimulate the VIIIth Nerve by providing an electric impulse substitution for the firing of hair cells. [[Cochlear implants]] are not only expensive, but require sophisticated programming in conjunction with patient training for effectiveness. People who have hearing impairments, especially those who develop a hearing problem in childhood or old age, require support and technical adaptations as part of the rehabilitation process.
| |
| | |
| ====Pre-lingual deafness====
| |
| :''Main article: [[Prelingual deafness]]''
| |
| ''Prelingual hearing impairment'' exists when the impairment is [[congenital]] or otherwise acquired before the individual has acquired [[Speech communication|speech]] and [[language]], thus rendering the disadvantages more difficult to treat because the child is unable to access audible /spoken communication from the outset. It is important to note that those children born into signing families have no delay in language development and communication. Most pre-lingual hearing impairment is due to an acquired condition, usually either disease or trauma; therefore, families commonly have no prior knowledge of deafness.
| |
| | |
| ====Post-lingual hearing impairment====
| |
| :''Main article: [[Post-lingual hearing impairment]]''
| |
| ''Post-lingual hearing impairment'' where hearing loss is adventitious after the acquisition of speech and language, usually after the age of six. It may develop due to [[disease]], [[Physical trauma|trauma]], or as a side-effect of a medicine. Typically, hearing loss is gradual, and often detected by family and friends of the people so affected long before the patients themselves will acknowledge the disability. Common treatments includes hearing aids and learning lip reading. Loneliness and depression can arise as a result of isolation (from the inability to communicate with friends and loved ones) and difficulty in accepting their disability.
| |
| | |
| ===Hard-of-hearing===
| |
| People who are ''hard of hearing'' have varying amounts of hearing loss but usually not enough to be considered deaf. Many people who are deaf consider spoken language their primary language and consider themselves "hard of hearing". How one classifies themselves relative to hearing loss or deafness is a very personal decision and reflects much more than just their ability to hear.
| |
| | |
| The phrase ''hard of hearing'', normally used as an adjective or adverb, can also be used as a noun, referring to people with hearing impairment as the ''hard of hearing''. People who consider themselves [[deaf culture|culturally deaf]], prefer the term "hard of hearing" or "deaf", and perceive "hearing impaired" as an insult.
| |
| | |
| Hearing impaired persons with partial loss of hearing may find that the quality of their hearing varies from day to day, or from one situation to another or not at all. They may also, to a greater or lesser extent, depend on both hearing-aids and lip-reading. They may perhaps not always be aware of it, but they do admit to it being important to see the speaker's face in conversation.
| |
| | |
| Many people with hearing loss have better hearing in the lower frequency ranges (low tones), and cannot hear as well or at all in the higher frequencies. Some people may merely find it difficult to differentiate between words that begin with consonantal sounds such as the fricatives or sibilants, z, or th, or the plosives d, t, b, or p. They may be unable to hear thin, high-pitched or metallic noises, such as birds chirping or singing, clocks ticking, etc. Often, they are able to hear and understand men's voices better than women's.
| |
| | |
| Others will find their condition so much worse if circumstances in their immediate environment affect the way they are able to use their hearing aids, or prevent them from employing their speech reading skills. A room with a high ceiling and a lot of [[reverberation]] will affect the sound of a speaker's voice adversely. The position of the listener, too, sitting at a right angle to the speaker at a long seminar table, thus being able to hear only with one, maybe the ineffectual ear, can make a difference. Difficulties can also arise for the listener trying to lip-read, if the speaker is sitting with his back against the light-source and is in this way obscuring his face. A rule of thumb is that bright lighting is to the hearing-impaired what noise is to the hearing; a source of distraction.
| |
| | |
| The speaker's accent; the topic under discussion, possibly with many unfamiliar words; the softness of his voice; possibly his having a [[speech impediment]]; a habit of holding a hand in front of his mouth or turning his face away at times: all these tendencies cause problems to the hard-of-hearing, especially when they have to rely on lip-reading. The rustling of papers, and notebook pages being turned are precisely the noises that will be the first thing hearing-aids pick up.
| |
| | |
| Noisy situations are especially difficult, because hearing loss not only affects the ability to hear sounds, but also to localize and filter out background noise.
| |
| | |
| ===Unilateral hearing loss===
| |
| People with [[unilateral hearing loss]] (single sided deafness/SSD) can hear normally in one ear, but have trouble hearing out of the other ear.
| |
| Problems with this type of deficit is inability to localize sounds (ie. unable to tell where traffic is coming from)
| |
| and inability to process out background noise in a noisy environment, such as in a restaurant.
| |
| | |
| ==Social impact==
| |
| ===Pre-lingual impairment===
| |
| ''See also: [[Prelingual deafness]]''
| |
| | |
| In children, hearing loss can lead to social isolation for several reasons. First, the child experiences delayed [[social development]] that is in large part tied to delayed [[language acquisition]]. It is also directly tied to their inability to pick up auditory social cues. This can result in a deaf person becoming generally irritable. A child who uses sign language, or identifies with the [[Deaf culture|deaf sub-culture]] does not generally experience this isolation, particularly if he/she attends a school for the deaf, but may conversely experience isolation from his parents if they do not know [[sign language]]. A child who is exclusively or predominantly oral (using speech for communication) can experience social isolation from his or her hearing peers, particularly if no one takes the time to explicitly teach her social skills that other children acquire independently by virtue of having normal hearing. Finally, a child who has a severe impairment and uses some sign language may be rejected by his or her deaf peers, because of an understandable hesitation in abandoning the use of existent verbal and speech-reading skills. Some in the deaf community can view this as a rejection of their own culture and its mores, and therefore will reject the individual preemptively.
| |
| | |
| ===Post-lingual impairment===
| |
| Those who lose their hearing later in life, such as in late adolescence or adulthood, face their own challenges. For example, they must adjust to living with the adaptations that make it possible for them to live independently. They may have to adapt to using hearing aids or a cochlear implant, develop speech-reading skills, and/or learn sign language. The affected person may need to use a [[Teleprinter|TTY]] (teletype), interpreter, or relay service to communicate over the telephone. Loneliness and depression can arise as a result of isolation (from the inability to communicate with friends and loved ones) and difficulty in accepting their disability. The challenge is made greater by the need for those around them to adapt to the person's hearing loss.
| |
| | |
| Many relationships have suffered because of the anger that occurs when there is general miscommunication between family members. Generally, it's not only the person with a hearing disability that feels isolated, but others around them who feel they are not being "heard" or paid attention to, especially when the hearing loss has been gradual. Many people opt not to choose hearing aids for fear of looking old, since hearing loss is usually associated with old age, which equals ineffectiveness in some societies. Family members then feel as if their hearing loss partner doesn't care about them enough to make changes to reduce their disability and make it easier to communicate.
| |
| | |
| ==Medical treatments==
| |
| ===Approaches===
| |
| Cleaning of ear canal (usually occurs during physical exam) to remove cerumen or a foreign body can restore hearing.
| |
| | |
| In addition to [[hearing aids]] there exist [[cochlear implant]]s of increasing complexity and effectiveness. These are useful in treating the mild to profound hearing impairment when the onset follows the acquisitions of language and in some cases in children whose hearing loss came before language was acquired. Recent research shows variations in effacacy but some promising studies[http://www.cid.wustl.edu/research/PPR/Geers/Geersppr.htm] show that if implanted at a very young age, some profoundly impaired children can acquire effective hearing and speech.
| |
| | |
| Ear protection can be used for the prevention of additional hearing loss.
| |
| | |
| ====Surgery and Device Based Therapies:====
| |
| * Myringotomy and tube placement (middle ear effusions)
| |
| * Hearing aids
| |
| * Middle ear implantable devices
| |
| * Cochlear implants
| |
| * Reconstructive middle ear surgery (including stapedectomy and tympanoplasty)
| |
| | |
| ===Views of treatments===
| |
| There is controversy in the culturally deaf community as to whether cochlear implants address wellness concerns, the overall health and psycho-emotional well-being of prelingually deaf children at all.
| |
| | |
| ==Gene therapy==
| |
| In 2005, there was success of the regrowth of cochlea cells in test subjects by a research team led by Dr. Yehoash Raphael from the University of Michigan. This study was conducted using guinea pigs as test subjects. [http://www.newscientist.com/article.ns?id=dn7003] It is important to note however, that the regrowth of cochlear hair cells does not imply the restoration of hearing sensitivity as the sensory cells may or may not make connections with neurons that carry the signals from hair cells to the brain.
| |
| | |
| A team led by Dr. Stefan Heller from Stanford University are pioneering stem cell research in the prospect of regrowth in cochlea cells.[http://news-service.stanford.edu/news/2005/november16/med-heller-111605.html]
| |
| | |
| ==Adaptations to hearing impairment==
| |
| Many hearing impaired individuals use certain assistive devices in their daily lives. Individuals can communicate by telephone using [[telecommunications devices for the deaf]] (TDD). This device looks like a typewriter or word processor and transmits typed text over the telephone. Other names in common use are textphone and minicom. A videophone can be used for distance communication using sign language. In 2004, mobile textphone devices came onto the market for the first time allowing simultaneous two way text communication. In the U.S., the UK, the Netherlands and many other western countries there are telephone relay services so that a hearing impaired person can communicate with a hearing person via a human translator. Wireless, internet and mobile phone/SMS text messaging are beginning to take over the role of the TDD. Other assistive devices include those that use flashing lights to signal events such as a ringing telephone, a doorbell, or a fire alarm. Video conferencing is also a new technology that permits signed conversations as well as permitting an [[American sign language|ASL]]-English interpreter to voice and sign conversations between a hearing impaired and hearing person, negating the need to use a TTY or computer keyboard.
| |
| | |
| ==Resources==
| |
| Many different [[assistive technology|assistive technologies]], such as hearing aids, are available to people who are hearing impaired. People with cochlear implants, hearing aids, or neither of these two devices also use additional communication devices to reduce the interference of background sounds, or to mediate the problems of distance from sound and poor sound quality caused by reverberation and poor acoustic materials of walls, floors and hard furniture. Three types of wireless, one-way wireless exist along with hard-wired devices. A wireless device used by people who use their residual hearing has two main components. One component sends the sound out to the listener, but is not directly connected to the listener with the hearing loss. The second component of the wireless system, the receiver, detects the sound and sends the sound to the ear of the person with the hearing loss. The three types of wireless devices are the FM system, the audio induction loop and the infra red system. Each system has advantages and benefits for particular uses. The FM system can easily operate in many environments with battery power. It is thus mobile and does not usually require a sound expert for it to work properly. The listener with the hearing loss carries a receiver and an earpiece. Another wireless system is the audio induction loop which permits the listener with hearing loss to be free of wearing a receiver provided that the listener has a hearing aid or cochlear implant processor with an accessory called a "telecoil". If the listener doesn't have a t-coil or telecoil, then she must carry a receiver with an earpiece. The third kind of wireless device for people with hearing loss is the infra red (IR) device which also requires a receiver to be worn by the listener. Usually the emitter for the IR device, that is, the component that sends out the signal, uses an AC adaptor. The advantage of the IR wireless system, is that people in adjoining rooms cannot listen in on conversations, and thus it is confidential and necessary for situations where privacy and confidentialitiy are required or chosen. Another way to achieve confidentiality is to use a hardwired amplifier which sends out no signal beyond the earpiece that is plugged directly into the amplifier. That amplifier of the hardwired device also has a microphone inside of it or plugged into it.
| |
| * [[Hearing dog]]s, a category of [[assistance dog]]s, are trained to help those with hearing impairments.
| |
| * The advent of the internet's World Wide Web and [[closed captioning]] has given the hearing impaired unprecedented access to information. Electronic mail and online chat have reduced the need for deaf and hard of hearing people to use a third-party [[Telecommunications Relay Service]] in order to communicate with the hearing and other hearing impaired people.
| |
| | |
| ==Bibliography==
| |
| *[[United States Environmental Protection Agency]] press release, April 2, 1974
| |
| | |
| == References ==
| |
| <references/>
| |
| | |
| ==See also==
| |
| *[[Audism]], discrimination against Deaf and hard-of-hearing people | | *[[Audism]], discrimination against Deaf and hard-of-hearing people |
| *[[Auditory brainstem response]] (ABR) test | | *[[Auditory brainstem response]] (ABR) test |
| *[[Deaf culture]] | | *[[Deaf culture]] |
| *[[Hearing loss with craniofacial syndromes]] | | *[[Hearing impairment with craniofacial syndromes]] |
| *[[King-Kopetzky syndrome]] | | *[[King-Kopetzky syndrome]] |
| *[[Models of deafness]] for a comparison of the medical, disability and cultural models of deafness. | | *[[Models of deafness]] for a comparison of the medical, disability and cultural models of deafness. |
| *[[Mondini Dysplasia]] | | *[[Mondini Dysplasia]] |
| *[[Noise induced hearing loss]] | | *[[Noise induced Hearing impairment]] |
| *[[Noise pollution]] | | *[[Noise pollution]] |
| *[[Post-lingual hearing impairment]] | | *[[Post-lingual hearing impairment]] |
| *[[Pre-lingual deafness]] | | *[[Pre-lingual deafness]] |
| *[[Tinnitus]] | | *[[Tinnitus]] |
| *[[Unilateral hearing loss]] | | *[[Unilateral Hearing impairment]] |
|
| |
|
| ==Quotations==
| | ==External Links== |
| *"[[Blindness]] cuts you off from things; deafness cuts you off from people." — [[Helen Keller]]
| |
| *"What matters deafness of the ear, when the mind hears. The one true deafness, the incurable deafness, is that of the mind." — Victor Hugo
| |
| *"Deaf people can do anything except hear." — I. King Jordan
| |
| | |
| ==External links== | |
| *[http://www.who.int/mediacentre/factsheets/fs300/en/ World Health Organization fact sheet on deafness and hearing impairment] | | *[http://www.who.int/mediacentre/factsheets/fs300/en/ World Health Organization fact sheet on deafness and hearing impairment] |
| *[http://www.nad.org/ National Association of the Deaf.] The NAD protects deaf and hard of hearing civil rights. | | *[http://www.nad.org/ National Association of the Deaf.] The NAD protects deaf and hard of hearing civil rights. |
| *[http://www.ifhohyp.org International Federation of Hard Of Hearing Young People]
| |
| *[http://hohadvocates.org/ Hard of Hearing Advocates] Non-profit foundation dedicated to helping those with hearing loss
| |
| *[http://insidedeafculture.com/ Inside Deaf Culture Website]
| |
|
| |
|
| {{Geriatrics}} | | {{Geriatrics}} |
| | {{WH}} |
| | {{WS}} |
|
| |
|
| | [[tr:Duyma kaybı]] |
| | [[es:Sordera]] |
| | [[fr:Surdité]] |
| | [[ja:聴覚障害者]] |
| | [[pt:Surdez]] |
| | [[ru:Нарушение слуха]] |
|
| |
|
| [[Category:Geriatrics]] | | [[Category:Geriatrics]] |
| Line 190: |
Line 75: |
| [[Category:Otolaryngology]] | | [[Category:Otolaryngology]] |
| [[Category:Noise pollution]] | | [[Category:Noise pollution]] |
| | [[Category:Symptoms]] |
| [[Category:Signs and symptoms]] | | [[Category:Signs and symptoms]] |
| [[Category:Needs patient information]]
| |
|
| |
|
| |
| [[tr:Duyma kaybı]]
| |
| [[bg:Увреден слух]]
| |
| [[de:Schwerhörigkeit]]
| |
| [[es:Sordera]]
| |
| [[fi:kuulovamma]]
| |
| [[fr:Surdité]]
| |
| [[he:חירשות]]
| |
| [[hu:Nagyothalló]]
| |
| [[ja:聴覚障害者]]
| |
| [[nl:Slechthorendheid]]
| |
| [[pt:Surdez]]
| |
| [[ru:Нарушение слуха]]
| |
| [[sv:Hörselskada]]
| |
|
| |
|
| |
| {{WikiDoc Help Menu}}
| |
| {{WikiDoc Sources}}
| |
