What Is a Hearing Screening?

If hearing loss cannot be detected in a timely manner, it will not only affect children (speech and cognitive development, education, employment, marriage and childbearing) and the family (communication barriers, psychological, economic burdens), but also become a heavy burden on society, affecting social and economic development . Modern science and technology can already perform early hearing detection and diagnosis on newborns and infants. If infants and young children who are clearly diagnosed as permanent hearing loss can be scientifically intervened and rehabilitated within 6 months of birth, the vast majority can return to the mainstream society.

Luo Renzhong	(Chief physician)	Department of Otorhinolaryngology, Guangzhou Women and Children's Medical Center
Gao Shengli	(Attending physician)	Department of Otorhinolaryngology, Guangzhou Women and Children's Medical Center

Newborn Hearing Screening (Universal Newborn Hearing Screening, UNHS) is an objective, objective, and natural electrophysiological test of otoacoustic emissions, automatic auditory brainstem response, and acoustic impedance. Quick and non-invasive examination. Reports at home and abroad show that there is a large difference in the incidence of hearing loss between normal newborns and high-risk newborns, with normal newborns at approximately 1% o to 3 and high-risk newborns at approximately 2% to 4%.

Western Medicine Name: Newborn hearing screening
English name: Universal Newborn Hearing Screening, UNHS

Affiliated Department: Faculty-
Contagious: Non-contagious

Overview of newborn hearing screening

Early hearing and detection programs for newborns and infants including hearing screening, diagnosis, intervention, follow-up, rehabilitation training, and effect evaluation are systematic and socially eugenic projects that require strict quality control.

Newborn Hearing Screening Newborn Hearing Screening Time

1. The initial screening process (first screening): the hearing screening during the newborn's hospitalization 3-5 days after birth.

2. The second screening process (re-screening): the first screening of the baby within 42 days of birth has not passed; or the initial screening is "suspicious"; even the initial screening has "passed" but belongs to high-risk hearing loss children such as intensive care Children in the ward need hearing screening.

Newborn Hearing Screening

There are two main types of newborn hearing screening subjects. One is normal newborns born to all; the other is newborns with high risk factors for hearing impairment.

Risk factors for hearing impairment:

1. 48 hours or more in the neonatal intensive care unit;

2. Premature birth (less than 26 weeks), or birth weight less than 1500 grams;

3 Hyperbilirubinemia

4 People with symptoms or signs of sensorineural and / or conductive hearing loss related syndromes;

5. People with a family history of permanent sensorineural hearing loss in childhood;

6. Craniofacial deformities, including microtia, malformations of the external ear canal, cleft palate, etc

7. Intrauterine infections in pregnant women, such as cytomegalovirus, herpes, and plasmoplasmosis.

8. Ototoxic drugs have been used in mothers during pregnancy;

9. Birth history of hypoxia and asphyxia, Apgar 0-4 points / 1min or 0-6 points / 5min;

10 Mechanical ventilation for more than 5 days;

11. Bacterial meningitis.

Newborn Hearing Screening Techniques

At present, the hearing screening instruments used in China mainly include oto-coustic emissions (OAE) and automatic auditory brainstem response (AABR). Screening results are either passed or failed. In general, the sensitivity and specificity of OAE and AABR can reach more than 95%, while OAE is slightly lower than AABR.

1. Otoacoustic emission: Otoacoustic emission is the reverse process of the normal sound wave entering the inner ear, that is, the acoustic energy generated by the cochlea passes through the middle ear structure and then through the tympanic membrane, into the outer hair cells of the cochlea, and the energy is reflected by the outer hair cells. , Recorded in the external ear canal. Otoacoustic emissions are classified into spontaneous otoacoustic emissions (SOAE) and evoked otoacoustic emissions (EOAE) according to the presence or absence of external acoustic stimuli. The latter is divided into transient induced otoacoustic emissions (TEOAE) and distortion products according to the type of stimulation. Otoacoustic Emission (DPOAE) and Frequency Stimulated Otoacoustic Emission (SFOAE). Otoacoustic emission is closely related to inner ear function. Any factor that damages the function of outer hair cells of the cochlea makes hearing damage more than 40dBHL, which can cause otoacoustic emission to be significantly reduced or disappeared. Moreover, Otoacoustic Emission is a non-invasive technique that is easy to operate and only takes 10 minutes to test both ears. Since TEOAE and DPOAE can be elicited in almost all normal ears, only 50-60% of normal ears can be recorded in SOAE. Therefore, TEOAE and DPOAE are commonly used for newborn hearing screening.

2. Automatic Auditory Brainstem Evoked Potential Technology (AABR): A fast, non-invasive ABR detection method implemented with a dedicated test probe. The emergence and use of AABR technology is intended to be used in conjunction with OAE technology in screening work to comprehensively check the functional status of the newborn's cochlea, auditory nerve conduction pathway, and brain stem. Newborns with high risk factors for hearing loss have a higher proportion of post-snail lesions. If you use OAE alone, you may miss the ethmoid lesions. Therefore, newborns with high risk factors for hearing loss should preferably use OAE and / or AABR for hearing screening to avoid missing the disease.

Newborn Hearing Screening

Normal births and NICU newborns should be screened differently.

1. Normal delivery: Screening otoacoustic emissions (OAE) or automatic auditory brainstem response (AABR) are used as first-line screening tools. All newborns should be screened for hearing before discharge; those who fail the screening should be rescreened within 42 days of birth. When rescreening, both ears should be rescreened. Even if only one ear fails during the initial screening, both screens should be rescreened. The re-screening instrument is the same as the initial screen.

2. Newborns and infants admitted to the NICU: The condition is stable, and AABR screening should be performed before discharge to prevent missing hearing loss (such as auditory neuropathy). Infants who fail the AABR test should be referred directly to a hearing center for rescreening, and a comprehensive audiological assessment including diagnostic ABR should be performed as appropriate.

3 Infants and young children who are hospitalized within 1 month of age (regardless of whether they live in the NICU or the general ward): When there is the possibility of delayed hearing loss (such as hyperbilirubinemia or blood culture-positive septicemia with indications of transfusion) Etc.), hearing should be re-screened before discharge.

4 In addition to trying to find the existing hearing loss during hearing screening, it is also necessary to analyze the medical history and family history to understand whether the subject has high risk factors for delayed hearing loss. Suspicious persons should follow up and follow up their hearing regularly. ^[1-3]

Impact of different factors on newborn hearing screening on screening results

Studies have shown that OAE or AABR for hearing screening [the results are affected by a variety of factors, including the following:

1. The retention of amniotic fluid, fetal fat, and fetal residues in the ear canal during neonatal period will attenuate or disappear the transmitted stimulus and outgoing response signal of the otoacoustic emission, resulting in the weakening or disappearance of the elicited signal of the otoacoustic emission. Therefore, it is especially important to clean the external ear canal with a small cotton swab before screening. In addition, the establishment of screening time is also one of the important factors affecting false positives, premature hearing screening will lead to an increase in false positives. Studies at home and abroad show that the appropriate time for initial screening is after 48 hours after birth.

2. Neonatal middle ear effusion is the main interfering factor affecting the 0AE test results. In children with middle ear effusion, whether the cochlea function is normal or not, the test results can be displayed as abnormal. The author believes that if the screening is not passed due to the middle ear effusion in the newborn, with the absorption of the middle ear effusion, the hearing of some children at the hearing diagnostic test after 3 months can be changed to normal. This condition is called "Yang to Yin" may be more appropriate.

3 Children have more body movements or irritability during screening. False positives will occur and should be avoided if possible. In addition, if you find a cold, nasal congestion, runny nose, cough or sore throat and respiratory sound weight in children, it is recommended to treat it first and wait for the symptoms to improve before rechecking to avoid false positives. If children's throat and breathing sounds are heavy, repeated treatment is not effective, and it is really necessary to understand the hearing situation, it is recommended to perform a diagnostic hearing directly.

4 Technology and operation are not standardized. Such as the earplug is not fully inserted into the external ear canal; the plug between the earplug and the wire is disconnected; the test environment does not meet the standards.

Diagnostic audiological assessment of newborn hearing screening

Infants and young children who have not passed the rescreening should undergo an audiological and medical evaluation at the age of 3 months to ensure that there is a congenital or permanent hearing loss within 6 months of age for intervention. That is, children who fail the rescreening should be tested by the hearing testing organization for otolaryngology, acoustic impedance, otoacoustic emission, auditory brainstem evoked potential detection, behavioral audiometry and other related examinations, and medical and imaging if necessary Assessment and make a diagnosis. For children with high risk factors for hearing loss, the time and number of individual hearing reassessments should be formulated according to the situation of delayed hearing loss that may occur. For infants and young children who have passed newborn hearing screening but have high risk factors for hearing loss, a hearing follow-up is conducted every 6 months at least 3 years old. If hearing loss is suspected, an audiological evaluation should be performed in time.

1. Test time: 3-6 months after birth.

2. Test environment requirements: soundproof shielded room with ambient noise below 30dB (A)

3. Objective hearing testing items include: diagnostic OAE, 1 kHz acoustic impedance test, short and short pure tones ABR, AERP, ASSR and bone conduction ABR.

4. Subjective hearing test items include: pediatric behavioral audiometry (BOA, VRA, PA, PTA), speech detection and auditory-speech development assessment form

Intervention after hearing diagnosis for newborn hearing screening

Newborn hearing screening, diagnosis and intervention is a complete hearing rehabilitation system project. Interventions are the last step and are the key to showing the outcome of congenital deafness rehabilitation. What method and when to intervene is important for the child's hearing, speech, and language rehabilitation. Interventions include medical interventions, hearing compensation or reconstruction, and training in auditory function and speech rehabilitation.

Medical intervention

Medical intervention refers to the method by which a physician proposes a medical diagnosis, that is, the cause, extent, and location of hearing loss, and uses treatment to restore hearing.

External auditory canal ridge: In newborns and infants, excessive ridges and difficult natural drainage can block the external auditory canal. In this case, the use of otoacoustic emission inspection can often cause the otoacoustic emission energy to disappear, and it can also affect the acoustic impedance inspection, and the external ear canal must be removed.

Acute secretory otitis media: Acute secretory otitis media in infants and young children is often caused by upper respiratory infections and immune allergies. It can cause tympanic fluid and hearing loss. According to clinical symptoms and otological microscopy and audiological examination, including ear acoustic emission, acoustic impedance examination, etc. can be clarified. Etiological treatment can be used, steroid hormones and anti-allergic drugs can be used, and ephedrine can be dripped in the nasal cavity. If the drug treatment is not effective, tympanic puncture and drainage can be used, incision and drainage, and ventilation tubes can be installed through the tympanic membrane. To improve and restore the hearing of children.

Congenital malformations of the outer ear and middle ear: according to the classification of deformities, different surgical treatments are used, on the one hand, external ear shaping and auricle reconstruction, and on the other hand, improving hearing. Deformed bilateral auricles and external auditory canal should be equipped with hearing aids as soon as possible to promote speech-language development.

2. Hearing compensation or reconstruction

Hearing compensation or reconstruction mainly includes hearing aid matching and cochlear implantation.

Hearing aids: Hearing aids are selected for children with permanent sensorineural hearing loss, and the degree of hearing impairment is generally moderate to severe. Some experts have suggested that hearing aids should be equipped with hearing aids for hearing correction and unilateral hearing loss. Optional hearing aids are also available. Hearing loss should be matched with bilateral hearing aids. The advantages of binaural matching are that it is helpful to distinguish the sound source, improve the sound source orientation ability, good integration effect, and increase the loudness of the sound.

Cochlear implant: The cochlear implant device is a converter that mimics the function of the human cochlea. It converts sound signals into electrical signals through a speech processor, passes them to the electrodes of the inner ear, directly excites the auditory nerve, and generates hearing. Cochlear implants are mainly divided into two parts: the implanted part (including the receiving device and multiple electrodes) and the external part (including the headset, transmitter, speech processor, etc.). For children with bilateral severe or very severe sensorineural hearing impairment, using hearing aids for 3 to 6 months has no obvious effect, and a pre-cochlear evaluation is performed at about 10 months. It is recommended that cochlear implant surgery be performed as soon as possible.

3 Auditory function training and speech-language rehabilitation training.

After the hearing aids are selected and the cochlear implant is used for hearing correction, the children need to be trained in hearing function and speech-speech rehabilitation. Physicians, audiologists, speech-speech therapists, special educators, and psychologists are required. It is important to establish long-term relationships with children to support their hearing and language development so that deaf children can hear sounds and understand speech.

Auditory function training includes the following: auditory perception; auditory attention; auditory positioning; auditory recognition; auditory memory; auditory selection; auditory feedback.

Speech-language rehabilitation training: Speech training procedures include phoneme, syllable, word, and short sentence training. For language rehabilitation, the following points should be followed: 1. Conditionally it is best to carry out systematic training in a rehabilitation center; 2. Stimulate the language interest of deaf children; 3. Step by step, from phonemes to short sentences, repeat key tasks; 4. Grasp speech acts Link, arrange the content of the dialogue. Speech-language rehabilitation training is assessed as speech recognition rate and speech expression rate. ^[4-6]

Follow-up and monitoring of newborn hearing screening

1. All infants and children under 3 years of age should use effective assessment methods for overall development assessment when health professionals or parents feel abnormal, including routine monitoring of indicators at various developmental stages, listening skills, and issues of concern to parents.

2. For infants and young children who fail the hearing and speech development checklist or simple audiometry test, or parents and guardians have problems with their hearing or speech, they should be recommended to the local designated otolaryngology or audiology center for audiology Assessment and speech-language assessment.