Editing Hearing loss (section)

==Diagnosis==
{{Main|Diagnosis of hearing loss}}
[[File:HearingExam.jpg|thumb|An [[audiologist]] conducting an [[audiometry|audiometric]] [[hearing test]] in a [[sound-proof]] testing booth|alt=a female medical professional is seated in front of a special [[sound-proof]] booth with a glass window, controlling diagnostic test equipment. Inside the booth a middle aged man can be seen wearing headphones and is looking straight ahead of himself, not at the [[audiologist]], and appears to be concentrating on hearing something]]

Identification of a hearing loss is usually conducted by a general practitioner [[medical doctor]], [[otolaryngologist]], certified and licensed [[audiologist]], school or industrial [[audiometrist]], or other audiometric technician. Diagnosis of the cause of a hearing loss is carried out by a specialist physician (audiovestibular physician) or [[otorhinolaryngologist]].

Hearing loss is generally measured by playing generated or recorded sounds, and determining whether the person can hear them. Hearing sensitivity varies according to the [[frequency]] of sounds. To take this into account, hearing sensitivity can be measured for a range of frequencies and plotted on an [[audiogram]]. Other method for quantifying hearing loss is a [[hearing test]] using a mobile application or hearing aid application, which includes a hearing test.<ref name=":2">{{cite journal | vauthors = Shojaeemend H, Ayatollahi H | title = Automated Audiometry: A Review of the Implementation and Evaluation Methods | journal = Healthcare Informatics Research | volume = 24 | issue = 4 | pages = 263–275 | date = October 2018 | pmid = 30443414 | pmc = 6230538 | doi = 10.4258/hir.2018.24.4.263 }}</ref><ref name=":3">{{cite journal | vauthors = Keidser G, Convery E | title = Self-Fitting Hearing Aids: Status Quo and Future Predictions | journal = Trends in Hearing | volume = 20 | pages = 233121651664328 | date = April 2016 | pmid = 27072929 | pmc = 4871211 | doi = 10.1177/2331216516643284 }}</ref> Hearing diagnosis using mobile application is similar to the [[audiometry]] procedure.<ref name=":2" /> Audiograms, obtained using mobile applications, can be used to adjust hearing aid applications.<ref name=":3" /> Another method for quantifying hearing loss is a speech-in-noise test. which gives an indication of how well one can understand speech in a noisy environment.<ref>{{cite journal | vauthors = Jansen S, Luts H, Dejonckere P, van Wieringen A, Wouters J | title = Efficient hearing screening in noise-exposed listeners using the digit triplet test | journal = Ear and Hearing | volume = 34 | issue = 6 | pages = 773–778 | date = 2013 | pmid = 23782715 | doi = 10.1097/AUD.0b013e318297920b | s2cid = 11858630 | url = https://lirias.kuleuven.be/bitstream/123456789/398543/2/Jansen_Ear%26Hearing_2013.pdf }}</ref> Otoacoustic emissions test is an objective hearing test that may be administered to toddlers and children too young to cooperate in a conventional hearing test. Auditory brainstem response testing is an electrophysiological test used to test for hearing deficits caused by pathology within the ear, the cochlear nerve and also within the brainstem.

A case history (usually a written form, with questionnaire) can provide valuable information about the context of the hearing loss, and indicate what kind of diagnostic procedures to employ. Examinations include [[otoscopy]], [[tympanometry]], and differential testing with the [[Weber test|Weber]], [[Rinne test|Rinne]], Bing and Schwabach tests. In case of infection or inflammation, blood or other body fluids may be submitted for laboratory analysis.  MRI and CT scans can be useful to identify the pathology of many causes of hearing loss.

Hearing loss is categorized by severity, type, and configuration. Furthermore, a hearing loss may exist in only one ear (unilateral) or in both ears (bilateral).  Hearing loss can be temporary or permanent, sudden or progressive. The ''severity'' of a hearing loss is ranked according to ranges of nominal thresholds in which a sound must be so it can be detected by an individual. It is measured in [[decibel]]s of hearing loss, or dB HL. There are three main ''types'' of hearing loss: [[conductive hearing loss]], [[sensorineural hearing loss]], and mixed hearing loss.<ref name="Peads2011" /> An additional problem which is increasingly recognised is [[auditory processing disorder]] which is not a hearing loss as such but a difficulty perceiving sound. The shape of an audiogram shows the relative ''configuration'' of the hearing loss, such as a [[Carhart notch]] for otosclerosis, 'noise' notch for noise-induced damage, high frequency rolloff for presbycusis, or a flat audiogram for conductive hearing loss. In conjunction with speech audiometry, it may indicate central auditory processing disorder, or the presence of a [[schwannoma]] or other tumor.

People with [[unilateral hearing loss]] or single-sided deafness (SSD) have difficulty in hearing conversation on their impaired side, localizing sound, and understanding speech in the presence of background noise.  One reason for the hearing problems these patients often experience is due to the [[head shadow effect]].<ref name="pmid15148171">{{cite journal | vauthors = Lieu JE | title = Speech-language and educational consequences of unilateral hearing loss in children | journal = Archives of Otolaryngology–Head & Neck Surgery | volume = 130 | issue = 5 | pages = 524–530 | date = May 2004 | pmid = 15148171 | doi = 10.1001/archotol.130.5.524 | doi-access = free }}</ref>

Idiopathic sudden hearing loss is a condition where a person as an immediate decrease in the sensitivity of their [[Sensorineural hearing loss|sensorineural hearing]] that does not have a known cause.<ref name=":5" /> This type of loss is usually only on one side (unilateral) and the severity of the loss varies. A common threshold of a "loss of at least 30 dB in three connected frequencies within 72 hours" is sometimes used, however there is no universal definition or international consensus for diagnosing idiopathic sudden hearing loss.<ref name=":5" />