Child hearing aidFive misunderstandings of fitting
Children with hearing impairment have significant differences with adults due to the degree of development of the auditory system, mental state, vision, intelligence, and responsiveness.Child hearing aidThe fitting must rely on the cooperation of the audiologist and the parents to achieve the desired results. Therefore, selecting, debugging and evaluating hearing aids for this group has always been a huge challenge and requires a dedicated child hearing aid fitter to be competent. However, the current situation of domestic hearing aid fitting for children is worrying. In particular, the following five typical misunderstandings:
Misunderstanding one:Neglecting the importance of the main observatio
Pediatric examination is significantly different from adulthood. Children do not have good coordination ability. General hospital examinations are used to obtain children’s hearing conditions through objective examinations, such as otoacoustic emissions, auditory brainstem evoked potentials and multi-frequency steady-state tests. However, we must fully understand the hearing situation of the child when we do the hearing aid fitting. Only objective examination is not enough. The combination of subjective and objective examination can be more realistic and close to the hearing situation of the child. Pediatric behavioral testing is the “gold standard” for understanding the degree of hearing loss in children.6Pediatric behavioral audiometry can be used for children aged up to age, including behavioral observation, visual enhancement audiometry, and game audiometry. Different test methods and frequency of detection are used according to the different age characteristics of the hearing loss children.
Myth 2: Wearing a hearing aid can understand the speech
The first reaction of many parents after their children wear a hearing aid is to ask the child to be called “Mother and Dad.” If the child can’t do it or even can’t understand it completely, the parents are often very disappointed, and then the hearing aid is not working well. This kind of eagerness to seek a state of mind can be understood. However, the main function of the hearing aid is to help the hearing-impaired child to improve the perception of the sound, that is, the hearing. It is not a drug, surgery, and it is impossible to see it immediately. You can “listen” before you can “understand”. The two cannot draw an equal sign. “Listen” is a psychoacoustic process that can be qualitatively and quantitatively: on the basis of satisfying other conditions, as the gain of hearing aids increases, the hearing-impaired children can hear more and more (loudness) and become more and more clear ( The signal-to-noise ratio is improved, and the sound range is also wider (listening to the sound of each frequency). The improvement of “understandable” takes a certain amount of time and requires long-term listening and rehabilitation training to have a good effect. Therefore, it is unrealistic to hope that the child can just hear the speech and respond accordingly when wearing the hearing aid.
Misunderstanding three: Does the hearing aid threshold indicate that the compensation is good in the “banana map”?
“Banana map” refers to the range of language frequency distribution and intensity distribution of normal people on the audiogram, and is the “gold standard” for hearing aid fitting. The hearing aid threshold indicates in the “banana map” that you can hear the greatest in daily life. Part of the speech sound (the closer to the upper edge, the better the listening). But it is not absolute.
The hearing aid threshold for children under two years old should be under the banana map, because the measured results are often inaccurate, and the actual hearing is definitely on the threshold.15Decibel or so. The principle of giving a hearing aid to a child is safe, comfortable, and audible, so the compensation should not be large when fitting.
Pediatric hearing compensation assessment also needs to be included in the real ear analysis, speech assessment comprehensive assessment of children’s hearing compensation.
Misunderstanding 4: Follow the adult fitting method
It is worth noting that at present, the fitting of children’s hearing aids in China basically follows the method of adults. Most hearing aid fitting centers lack the hardware and software foundation required for child hearing aid fitting. Hardware refers to testing the true ear-coupled cavity difference (RECD) equipment, accessories for debugging children’s hearing aids, etc.; software refers to the formulation software required for the fitting of hearing aids for children (DSL 5.0OrNAL-NL2), technical conditions for evaluating the effects of children’s hearing aids, etc. If these important conditions are not met, strictly speaking, it is impossible to effectively carry out the fitting of children’s hearing aids, and the effect will be affected.
Pediatric hearing rehabilitation takes ten years or more to achieve better results, and strict selection of qualifiedChild hearing aidThe fitting and service center is one of the prerequisites for successful rehabilitation.
Misunderstanding 5: One-time fitting, ignoring long-term hearing management
The ears of infants and young children are in the process of continuous development after birth, especially in the first two years after birth.7Gradually shaped after the age,10It stops after the age. During this period, the size of the auricle, the size of the external auditory canal, Hardness, direction, etc. will constantly change. However, current ear canal acoustic parameters for hearing aid fitting are based on average adult data. Studies have shown that the peak frequency of the neonatal ear canal resonance curve is adult2~3 Double; children’s true ear-coupled cavity difference5When I was old, I gradually approached the average of adults. Therefore, in reality, it is obviously wrong to use the average adult value to calculate the target gain and other important parameters for the child hearing aid fitting. In addition, the fitting is also Need to consider the characteristics of the outer ear of children, softer ear mold is better for children, and need to be constantly replaced to adapt to the development of the external auditory canal, to avoid acoustic feedback or excessive amplification. Therefore, regular review and evaluation are essential.
Different use environments, different auxiliary devices will affect the child’s hearing ability, so hearing loss children also need a comprehensive comprehensive hearing management service .