One, hearing assessment
1, reception, archiving
After the reception of deaf patients archived, including general information and specialized information.
General information includes name, gender, age, occupation, and contact information.
Specialized information includes the collection of medical history and general otologic examination.
The history should include details of the patient's and family's hearing loss, such as the duration of the hearing loss, whether it is stable, progressive, or fluctuating, the presence or absence of concomitant symptoms, the effects of previous treatments and/or interventions, and the ability to express oneself verbally.
In principle, a hearing impaired person should be diagnosed by a specialist before being fitted with a hearing aid.
2, audiology test
The audiology test for children under 3 years old includes behavioral audiometry (behavioral observation response audiometry, visual reinforcement audiometry or play audiometry), auditory brainstem response, multifrequency steady-state response, otoacoustic emission, and acoustic conductance.
The contents of audiological testing for hearing impaired persons over 3 years old include pure tone hearing threshold test, discomfort threshold test, speech audiometry, acoustic conductance, otoacoustic emission, and mental-intellectual evaluation.
Second, pre-selection
1, selection of hearing aids
For binaural hearing impaired people, generally binaural testing and fitting, subject to the conditions of the test can also be monaural testing and fitting, but should be pointed out that the shortcomings of monaural testing and fitting.
The hearing aids used should be in accordance with national or industry standards.
Hearing aids are categorized by shape into cassette, behind-the-ear and in-the-ear (custom-made), and by technical principle into analog and programmable hearing aids.
When choosing a hearing aid, more than two hearing aids should be recommended for the hearing impaired person to try on according to the hearing level and the performance that the hearing aid can achieve, combined with his/her financial condition, working and living environment, and personal preference.
2. Customized earmolds or in-the-ear (customized) shells
When customizing earmolds for behind-the-ear (BTE) machines or cassette machines, we first check the external auditory canal and the tympanic membrane, and then we take an ear impression and fill in the customization form.
When choosing a customized machine send the acquired ear impressions to the manufacturer along with the completed customization sheet, which should give as much complete information as possible to the manufacturer.
There are three types of ear molds: soft ear molds, semi-soft ear molds and hard ear molds.
The first two types of earmolds are often chosen for children, and hard earmolds for adults.
The shape of hard earmolds is related to the degree of hearing loss. In general, shell earmolds with good sealing are chosen for very severe and severe hearing loss; frame earmolds are chosen for severe and moderately severe hearing loss; and ear canal earmolds are chosen for moderately severe and moderate hearing loss.
The trade-offs, size and shape of the ventilation holes and the addition of different sizes of damper are decided according to the audiogram and the patient's subjective response.
Third, debugging
Debugging hearing aid electroacoustic parameters mainly include the true ear gain frequency response curve and the true ear loudest output frequency response curve. These parameters can be calculated by POGO, NAL, DSL and other prescription formulas.
When fitting an analog hearing aid, the compression line is selected according to the auditory dynamic range, such as: peak clipping (PC), automatic gain control (AGC), and wide dynamic range compression (WDRC).
When fitting programmable hearing aids, the gain and compression ratios of different frequency bands should be adjusted, and multiple programs should be set up to adapt to people with different types of hearing loss, and to use hearing aids in different acoustic environmental conditions.
When fitting, you can also refer to the prompts of the hearing aid fitting software for selection.
The selection of children's hearing aids should consider the mating of various auditory aids.
Four, hearing aid evaluation
1, hearing aid effect evaluation
behavioral observation, functional assessment, Ling's six tones, digital assessment, speech test, true ear analysis, questionnaire survey and other methods to evaluate the effect of hearing aid wear, and pay attention to the different strength of the given sound, different nature of the given sound signals, different listening environment on the amplification effect of the hearing aid.
The evaluation of the hearing aid effect includes the evaluation of the patient's expectation of the hearing aid and the evaluation of satisfaction.
2, tracking assessment
Hearing aids in the use of the process, its working condition may change; the user's hearing condition may be aggravated or alleviated; the user may also have new personalized needs.
Therefore, it is very important to follow up with the user regularly and make a new evaluation of the hearing aid wearing effect.
The follow-up time is usually every one month in the first year of wearing, and every six months thereafter, but if the user has any special conditions, he/she is not subject to this time limit and can be seen at any time.
In addition to the hearing aid effect evaluation method, the tracking evaluation should also check the ear and hearing of the hearing impaired person.