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Objective: To analyze the mutation spectrum of 23-site chip newborn deafness genetic screening in Beijing, and to provide basis for genetic counseling and clinical diagnosis and treatment. Methods: The study included 21 006 babies born in Beijing from December 2022 to June 2023. All subjects underwent newborn deafness genetic screening in Beijing Tongren Hospital, covering 23 variants in 4 genes, the GJB2 gene（c.35delG, c.176_191del16, c.235delC, c.299_300delAT, c.109G>A, c.257C>G, c.512insAACG, c.427C>T, c.35insG）, SLC26A4 gene（c.919-2A>G, c.2168A>G, c.1174A>T, c.1226G>A, c.1229C>T, c.1975G>C, c.2027T>A, c.589G>A, c.1707+5G>A, c.917insG, c.281C>T）, Mt12SrRNA （m.1555A>G, m.1494C>T） and GJB3 gene（c.538C>T）. The mutation detection rate and allele frequency were analyzed. Results: The overall mutation detection rate was 11.516%（2 419/21 006）, with the GJB2 gene being the most frequently involved at 9.097%（1 911/21 006）, followed by the SLC26A4 gene at 2.123%（446/21 006）, the GJB3 gene at 0.362%（76/21 006） and Mt12SrRNA at 0.176%（37/21 006）. Among the GJB2 genes, c.109G>A and c.235delC mutation detection rates were the highest, with 6.579%（1 382/21 006） and 1.795%（377/21 006）, respectively. Of the SLC26A4 genes, c.919-2A>G and c.2168A>G had the highest mutation rates of 1.423%（299/21 006） and 0.233%（49/21 106）, respectively. Regarding the allele frequency, GJB2 c.109G>A was the most common variant with an allele frequency of 3.359%（1 411/42 012）, followed by the GJB2 c.235delC at 0.897%（377/42 012） and the SLC26A4 c.919-2A>G at 0.719%（302/42 012）. Conclusion: 23-site chip newborn deafness genetic screening in Beijing showed that GJB2 c.109G>A mutation detection rate and allele frequency were the highest. This study has enriched the epidemiological data of 23-site chip genetic screening mutation profiles for neonatal deafness, which can provide evidence for clinical practice., Competing Interests: The authors of this article and the planning committee members and staff have no relevant financial relationships with commercial interests to disclose., (Copyright© by the Editorial Department of Journal of Clinical Otorhinolaryngology Head and Neck Surgery.)

Objective: To investigate the clinical audiological characteristics of children referred from maternal and child institutions and analyze the high risk factors of hearing loss, so as to provide scientific basis for further improvement of children's ear and hearing care. Methods: The subjects of this study were 868 children who were referred by maternal and child institutions in Beijing to the otology outpatient of Beijing Tongren Hospital, Capital Medical University for hearing diagnosis. All subjects underwent acoustic immittance, auditory brainstem response, distortion products otoacoustic emission and other audiological tests. Children were divided into groups according to the age of diagnosis: 0-<3 months group（242 cases）, 3-<6 months group（328 cases）, 6-<12 months group（180 cases）, ≥12 months group（118 cases）, the results of hearing diagnosis, hearing loss degree and types, the relationship between high risk factors and hearing loss in each group were compared and analyzed. Results: The age of diagnosis of 868 children was（7.13±8.29） months. 488 cases with hearing loss accounted for 56.22% and 380 cases with normal hearing accounted for 43.78%. Proportion of different degree of hearing loss of 792 ears from high to low was as follows: mild, 366 ears（46.21%）; moderate, 214 ears（27.02%）; severe, 151 ears（19.07%）; profound, 61 ears（7.70%）. There were statistically significant differences in the proportion of different hearing loss degree among 0-<3 months group, 3-<6 months group, 6-<12 months group and ≥12 months group（ P <0.001）. Pairwise comparison between groups showed that the proportion of mild hearing loss of 0-<3 months group was higher than that in the other three groups（ P <0.05）, there was no significant difference of moderate hearing loss among all groups（ P >0.05）, the proportion of severe hearing loss of ≥12 months group was higher than that of 0-<3 months group（ P <0.05）. The proportion of profound hearing loss with 0-<3 months group was lower than the other three groups（ P <0.05）. In 792 ears with hearing loss, sensorineural hearing loss accounted for 67.42%, conductive hearing loss accounted for 20.71% and mixed hearing loss accounted for 11.87%. Among 98 cases with high risk factors for hearing loss, 58 cases（59.18%） were diagnosed with hearing loss. The incidence of hearing loss with high risk factors ranked from high to low was: craniofacial malformation（93.75%）, family history/congenital genetic syndrome（61.11%）, neonatal intensive care unit（NICU） hospitalization（46.43%） and others（20.00%）. Conclusion: Referrals from maternal and child institutions play an important role in the early detection of children with mild to moderate sensorineural hearing loss. Children with craniofacial malformation, family history/congenital genetic syndrome, hospitalization history of NICU and other high risk factors have a high incidence of hearing loss and should be attached with great importance., Competing Interests: The authors of this article and the planning committee members and staff have no relevant financial relationships with commercial interests to disclose., (Copyright© by the Editorial Department of Journal of Clinical Otorhinolaryngology Head and Neck Surgery.)

Objective: This study aimed to provide better understanding of the otolaryngologic features, combined with ophthalmologic and neurologic characteristics in mitochondrial encephalomyopathy（MEM）, and to help ENT and auditory practitioner making correct diagnosis as well. Methods: Twenty-eight patients with MEM were enrolled between September 2001 and January 2020. Information about family histories and clinical symptoms was retrospectively analyzed. All patients underwent otorhinolaryngological, ophthalmological and neurological examinations, including: pure-tone audiometry, acoustic immittance（AI）, distortion-product otoacoustic emissions（DPOAE）, auditory brainstem response（ABR）, cochlear micropotential（CM）, speech discrimination score（SDS）, electroneurography（ENoG）, computed tomography（CT） of the temporal bone and cranial magnetic resonance weighted imaging scan（MRI）, muscle biopsy and mtDNA gene testing. Results: ENT subjective manifestations were present in 15 cases （53.6%） with sensorineural hearing loss（SNHL）, 4（14.3%） with tinnitus, 4（14.3%） with facial weakness, 3（10.7%） with dysphagia, 1（3.6%） with auditory agnosia. Ophthalmological and neurological symptoms included ptosis in 16 cases （57.1%）, exercise intolerance in 16（57.1%）, optic atrophy in 15（53.6%）, muscular atrophy in 6（21.4%）, and stroke-like episodes in 5（17.9%）. The results of objective examinations were as follows: DPOAE were not elicited in 18（64.3%） cases, ABR abnormalities in 18（64.3%） cases, hearing threshold shift in 15（53.6%） cases, AI normal and CM was not detected in all cases, SDS decreased in 6（21.4%） cases, facial ENoG abnormalities in 4（14.3%） cases, laryngeal ENoG abnormalities in 3（10.7%） cases, EMG abnormalities in 6（21.4%） cases, and ECG abnormalities in 8（28.6%） cases. Temporal CT were normal, but cranial MRI abnormalities were found in 19 cases（67.9%）, including central nerve demyelination, white matter hyperintensities, generalized cerebellar and cerebral atrophy, multiple cortical/subcortical infarct-like lesions, basal ganglia calcification. Conclusion: Multisystemic syndromes in MEM can present as a variety of otolaryngological, ophthalmological and neurological abnormalities, such as ptosis, audio-visual disturbance, exercise intolerance and stroke-like episodes etc. SNHL, tinnitus, auditory agnosia, facial weakness and dysphagia were ENT specific manifestations. SNHL in MEM is bilateral symmetrical progressive or of sudden onset since teenage. mtDNA testing may be helpful for adolescent patient whose SNHL was associated with neuromuscular symptoms. Muscle biopsy should be considered when middle-aged patients developed facial weakness and dysphagia. DPOAE and ABR are the optimal objective audiometric tests to monitor the progression of MEM associated with SNHL., Competing Interests: The authors of this article and the planning committee members and staff have no relevant financial relationships with commercial interests to disclose., (Copyright© by the Editorial Department of Journal of Clinical Otorhinolaryngology Head and Neck Surgery.)

Objective: To analyze the current status of newborn deafness gene screening from 2016 to 2017 in multiple regions of China, and to provide a reference for further promotion and application. Method: The "newborn deafness gene screening questionnaire" was sent to 41 institutions in eastern, central and western China after expert demonstration. The survey content included status of genetic screening, screening methods, the number of screenings, and the status of positive detections from January 1st, 2016 to December 31th, 2017. Each institution returned the questionnaire, the investigator conducted data verification and quality sampling. Finally, we performed analysis of screening methods and the positive detection rate of each gene on questionnaires with complete data. Result: Forty-one questionnaires were sent out and 41 were returned, the questionnaire return rate was 100%, in which 12 questionnaires were complete. Of the 41 institutions, 15 carried newborn deafness gene screening, with a rate of 36.59%（15/41）. The highest rate was in the east（72.22%, 13/18）, and the differences among the regions were statistically significant. As for the screening methods, among 12 questionnaires with complete data, 9 variants in 4 genes and 20 variants in 4 genes accounted for the highest proportion, both with the rate of 33.33%（4/12）, followed by 15 variants in 4 genes（25%, 3/12） and 5 variants in 3 genes（8.34%, 1/12）. A total of 340, 521 neonates were included in the study, and 17, 036 were positive for screening, with a positive rate of 5.00%. Among them, the single heterozygous mutation rate of GJB2 gene was 2.43%（8269/340, 521）, the biallele mutation rate was 0.02%（56/340, 521）,the single heterozygous mutation rate of SLC26A4 gene was 1.99%（6771/340, 521）, the biallele mutation rate was 0.01%（39/340, 521）,the single heterozygous mutation rate of GJB3 gene was 0.33%（1140/340, 521）, the mitochondrial 12SrRNA gene mutation rate was 0.22%（746/340, 521） and the double-gene heterozygous mutation rate was 0.004%（15/340, 521）. Conclusion: From 2016 to 2017, the newborn deafness gene screening is more extensive in the eastern region of China than in the central and western regions. In institutions that have carried out deafness gene screening, 9 variants in 4 genes and 20 variants in 4 genes are widely used; the GJB2 gene and SLC26A4 gene mutations are the most common. The results could provide references for areas where deafness gene screening is about to be performed., Competing Interests: The authors of this article and the planning committee members and staff have no relevant financial relationships with commercial interests to disclose., (Copyright© by the Editorial Department of Journal of Clinical Otorhinolaryngology Head and Neck Surgery.)

The symptoms of hidden hearing loss（HHL） are concealed, mainly manifested as defects in the threshold upper auditory function, which are related to noise exposure, aging and drug damage. There is no definite evidence to prove that whether the three factors participate in mechanism of synaptic damage in the cochlea. The clinical audiological characteristics of HHL are mostly as follows: the normal threshold of PTA and the wave response of ABR; the amplitude of the CAP of ABR wave Ⅰ or ECochG is lower at medium and high stimulation intensity; the lower speech recognition rate under noise, etc. Ultra-high frequency pure tone audiometry, a series of objective audiological examinations, such as ABR, ECochG and frequency-following response, speech audiometry under noise, noise exposure questionnaire evaluation were applied to detect HHL at early stage., Competing Interests: The authors of this article and the planning committee members and staff have no relevant financial relationships with commercial interests to disclose., (Copyright© by the Editorial Department of Journal of Clinical Otorhinolaryngology Head and Neck Surgery.)

Objective: The aim of this study is to explore the genotype and hearing phenotype of deaf infants with mutation of GJB2 gene. Method: Subjects were 121 infants with GJB2 gene mutations who were treated in the Children's Hearing Diagnosis Center of Beijing Tongren hospital. All subjects were accepted to undertake the universal newborns hearing screening（UNHS） and series of objective audiometry, including auditory brainstem response, distortion product otoacoustic emission, auditory steady-state response and other audiological tests. All subjects were screened for nine pathogenic variants in four genes or all exons of the GJB2 gene, and then were diagnosed as infants with GJB2 gene mutations. Initially, analyzing their genotypes and hearing phenotypes generally. Then, the subjects were divided into two groups according to the genotypes: T/T group（truncated/truncated mutations, 89 cases） and T/NT group（truncated/non-truncated mutations, 32 cases）. Chi-square test was used to analyze the results of UNHS, hearing degree, audiogram patterns and symmetry/asymmetry of binaural hearing phenotype. Eventually, analyzing the results of UNHS. Result: The most common truncated mutation was c.235delC（64.88%, 157/242） and the most common non-truncated mutation was c.109G>A（11.16%, 27/242）. The homozygous mutation of c.235delC/c.235delC was the dominant in T/T group（38.84%, 47/121）, and the compound heterozygous mutation of c.235delC/c.109G>A was the dominant in T/NT group（18.18%, 22/121）. 81.82%（99/121） of subjects failed in UNHS, including 74.38%（90/121） with bilateral reference, 7.44%（9/121） with a single pass. The refer rate of UNHS of group T/T and T/NT were 86.52%（77/89） and 68.75%, respectively. There was a statistically significant difference between the two groups（ P <0.05）. 85.95%（104/121） of subjects were diagnosed as hearing loss and 14.05%（17/121） of subjects were diagnosed as normal hearing. The degree of hearing loss: profound, severe, moderate and mild were 31.40%（38/121）, 19.01%（23/121）, 24.79%（30/121） and 10.74%（13/121）, respectively. There was no subjects with normal hearing in T/T group and individuals with severe and profound hearing loss accounted for the highest proportion（65.17%, 58/89）, while in T/NT group, normal hearing accounted for 53.13%（17/32） and mild and moderate hearing loss accounted for the highest proportion（37.5%, 12/32）. There was statistically significant difference between the two groups（ P <0.05）. Of 104 patients（208 ears） with hearing loss, the audiogram patterns: flat, descending, ascending, residual, Valley and other types were 49.03%（102/208）, 12.02%（25/208）, 8.65%（18/208）, 7.69%（16/204）, 3.36%（7/204） and 19.23%（40/204）, respectively. The two most common types in T/T group were flat（47.19%, 84/178） and other types（20.22%, 36/178）, while in T/NT group were flat（60.00%, 18/30） and ascending（20.00%, 6/30）. There was statistically significant difference between the two groups（ P <0.05）. There were 50 cases（48.07%） with symmetrical hearing phenotype and 54 cases（51.93%） with asymmetrical hearing phenotype. Asymmetry was predominant in T/T group（53.93%, 48/89）, and symmetry was predominant in T/NT group（60.00%, 9/15）. There was no statistically significant difference between the two groups（ P >0.05）. Conclusion: In this study, c.235delC/c.235delC homozygous mutation was dominant in T/T group and c.235delC/c.109G>A heterozygous mutation was dominant in T/NT Group. The hearing phenotypes in T/T group were mostly bilateral asymmetric severe hearing loss, and those in T/NT Group were bilateral symmetric mild to moderate hearing loss, special attention should be paid to the audiological characteristics of different genotypes., Competing Interests: The authors of this article and the planning committee members and staff have no relevant financial relationships with commercial interests to disclose., (Copyright© by the Editorial Department of Journal of Clinical Otorhinolaryngology Head and Neck Surgery.)

The incidence of hearing impairment in neonatal intensive care unit (NICU) was much higher than that of well-baby nursery. The incidence of the former was 2%-4%, whereas that of the latter was 0.1%-0.3%. Furthermore, the incidence of auditory neuropathy spectrum disorder, progressive and delayed hearing loss was also higher than those of other infants. Therefore, the newborn hearing screening program in NICU has become an important part of pediatric audiology. In this paper, we reviewed the previous studies and suggested the special procedure of hearing screening and following-up which based on the physiological and pathological characteristics of NICU in order to detect hearing impaired as early as possible.

Objective: To determine GJB2 allelic mutant and estimate probability of hereditary hearing loss in newborn with GJB2 heterozygous mutation in Beijing., Method: We performed genetic testing for sequencing of GJB2 gene for searching GJB2 allelic mutant in 915 newborn who received newborn deafness gene screening (GJB2 c. 235delC, GJB2 c. 299&#95;300delAT, GJB2 c. 176191del16, GJB2 c. 35delG) in Beijing Tongren hospital, and the mutation were classified to pathogenic mutation,undefined variant and polymorphism., Result: Four hundred (43.72%, 400/915) newborn were detected to carry at least one mutation allele in GJB2. 3 (0.33%, 3/915) newborn had pathogenic mutations (c. 94C>T, c. 380G>T, c. 344T>G); 62 (6.76%, 62/915) newborn carried 14 undefined variant, 36 newborn had c. 109G>A (58.06%, 36/62),13 newborn had c. 368C>A (20.97%,13/62), six (c. 268C>G, c. 282C>T, c. 294G>C, 456C>T, c. 501G>A, c. 587T>C) are novel; 335 (36.61%, 335/915) newborn were polymorphism., Conclusion: The probability of hereditary hearing loss is 7.09% in newborn with GJB2 heterozygous mutation in Beijing. It is noteworthy that c. 109G>A, c. 368C>A occupy a high proportion.

Objective: To explore the found ways and first diagnosis age of children with large vestibular aqueduct, and their relations with hearing loss., Method: Medical histories of 122 cases of children diagnosed with large vestibular aqueduct by HRCT or MRI had been collected from January 2009 to April 2014 in our hospital children's hearing diagnosis center clinic. Found ways comprise of accepting universal newborn hearing screening (UNHS) group and unaccepting UNHS group. Accepting UNHS children were divided into two ears unpassing group, single ear unpassing group and passing group. The patients in unaccepting UNHS group were divided into not sensitive to sounds, speech stunting, sudden hearing loss, and other group. Analysis the relationship between the found ways and first diagnosis age and their relations with hearing loss., Result: There are 84 cases (68.85%) accepting UNHS, the average age of first diagnosis was (17.24 ± 17.08) months; 37 cases (31.15%) are not accepting UNHS. The average age of first diagnosis was (30.92 ± 18.21) months. The average first diagnosis age of accepting UNHS group was more earlier than the unaccepting UNHS group. The difference was statistically signif- icant (P < 0.01). There were 57 cases (67.85%) whose two ears not pass UNHS; 15 cases (17.86%) single ear not pass; namely the referral rate was 85.71%; 12 cases (14.29%) pass the test. The first diagnosis age of passing UNHS group was more later than two ears unpassing group (P < 0.001). In the unaccepting UNHS group, the average first diagnosis age of not sensitive to sounds group (19.69 ± 11.16 months) was more earlier than words dysplasia group (37.13 ± 15.62 months) and sudden hearing loss group (47.40 ± 24.70 months) (P < 0.01). The difference in the degree of hearing loss between accepting UNHS and unaccepting UNHS group had no statistical significance (P > 0.05). In unaccepting UNHS group ,the average first diagnosis age of the mild-to-moderate hearing loss group was later than the very severe hearing loss group (P < 0.01)., Conclusion: Most of large vestibular aqueduct children can be found and receive diagnosis early by UNHS. But part of these patients with late-onset or progressive hearing loss, especially these with mild-to-moderate hearing loss cannot be found early, which should arouse our attention.

Deafness refers to different degrees of hearing loss (HL). The factors leading to HL are complex, among which heredity is a major one. Nonsyndromic hearing loss (NSHL) accounts for 80% of hereditary deafness. More than 140 genes have been regarded to be closely related to NSHL. The mutation of GJB2 (gap junction protein, beta 2) gene accounts for 80% of NSHL and more than 50% of children NSHL, playing the most important role in deafness genes. This paper reviewed the studies on the association between GJB2 gene mutation and HL to provide reference for genetic diagnosis and counseling.

Objective: In order to extend the knowledge of auditory neuropathy spectrum disorder (ANSD), the clinical data of a group of infants and young children with this disorder was reported., Method: This retrospective study involved 84 cases (151 ears). The subjects aged from 2 months to 6 years old. Descriptive analysis was carried out on case history, audiological and imaging results and the outcome of cochlear implantation., Result: There were a variety of case history, including 11 of hyperbilirubinemia, 2 of family history of deafness, 3 of hypoxia, 1 of prematurity, 1 of nuclei basales pathology, 2 of congenital atelencephalia,and 13 of cochlear nerve deficiency (CND). The audiological results varied too. Click ABR ranged from no response at the maximum output level to Wave V thresholds as low as 70 dB nHL. Behavioral thresholds were mild in 1, moderate in 2 and profound in 20. The inner ear MRI were normal in 16 cases, CND in 12 and CND accompanied by periventricular leukomalacia in 1. 5 cases were implanted in the affected ear. The results in 3 were comparable with that of cochlear loss, 1 were less effective than that of cochlear loss, 1 became none user of the device., Conclusion: ANSD is a heterogeneous group with a wide variety on case history, audiological and imaging results and the outcome of cochlear implant. Therefore, comprehensive clinical examinations are necessary so that individualized intervention program can be made.

Objective: To evaluate the feasibility of a rapid genetic diagnosis technique in molecular genetics study of hearing loss., Method: One hundred and ten subjects including 54 with moderate to profound non-syndromic sensorineural hearing loss were enrolled in this study. All with informed consents. Their peripheral blood samples were taken and tested using Hearing Loss Array Kit developed by Capital Bio. Nine hot mutation sites from 4 high risk genes were tested each., Result: The overall positive rate in this cohort was 50.9%, while the positive rate among 54 hearing loss cases was 59.3%. DNA sequence analysis showed 100% coincident with gene chip results., Conclusion: This Hearing Loss Array Kit (gene chip) has a high positive detection ratio, its characteristics such as rapid high-flux sensitive and high specific make it possible and promising in future screening and diagnosis in patients with sensorineural hearing loss. Molecular genetic diagnosis also has a profound value in deafness prevention.

Objective: To investigate the feasibility of universal newborn hearing screening in countryside in order to provide reliable evidence in launching this program all over the countryside of China., Method: Subjects were 12,638 infants who were born in 9 counties from Jan 2004 to Dec 2005. TEOAE was used for the fast hearing screening. Infants were screened on the 2-7 days after the birth. The re-screening was conducted in 4-6 weeks if failed in the initial screening, and follow-up were provided continually if they also failed in the re-screening., Result: Ten thousand eight hundred and forty-five of 12,638 (85.8%) were screened including 9,963 (91.9%) normal newborns and 882 (8.1%) newborns with high-risk. Seven thousand four hundred and fifty (68.7%) newborns passed the initial screening, and 3,395 (31.3%) people failed. One thousand seven hundred and ninety-three (14.2%) infants were refused to be screened. Only 2,536 (74.7%) were re-screened on time, and 859 (25.3%) did not receive re-screening. One hundred and twenty were failed in the re-screening or first screening, and 79 (65.8%) of them received diagnostic assessment. Among the infants received diagnostic assessment, 6 (7.6%) cases were found to have profound hearing loss in both ears, 9 (11.4%) cases were found to be severe hearing loss (7 in both ears and 2 in single ear), 11 (13.9%) cases were found to be moderate hearing loss (5 in both ear and 6 in single ear), 26 (32.9%) were found to have slight hearing loss (11 in both ear and 15 in single ears), and 27 (34.2%) were normal. Fifty-two infants were diagnosed as hearing loss with a prevalence of congenital hearing loss (in binaural and monaural) of 0.5% (52/10845) and a prevalence of bilateral hearing loss of 0.3% (29/10845). A prevalence of congenital hearing loss was 0.2% (22/9,963) in well infants and 3.4% (30/882) in high risk infants. Among the 13 cases of children with severe and profound hearing loss in both ears children, 8 (61.5%) cases were fitted with hearing aids and 1 (7.7%) case was implanted with cochlear implants., Conclusion: It is necessary and feasible to conduct hearing screening program in the rural area. However, the suitable model to perform the program in the countryside needs to be set up as soon as possible in order to get more poor infants to participate into the hearing screening program for free and increase the screening rate.

Objective: To discuss the multiple-frequency probe tones tympanograms and the normal ranges of admittance, susceptance and conductance in normal newborns., Method: Tympanometries with 226 Hz, 678 Hz and 1000 Hz probe tones were obtained from newborn infants with normal TEOAE and DPOAE(55 infants, 110 ears), analysed multiple-frequency prone tones tympanograms and values of admittance, susceptance and conductance by using GSI-33 middle ear analyzer., Result: 226 Hz tympanograms for admittance, susceptance and conductance main were W-shaped, the percentages were 90.0%, 99.1% and 85.5%. 678 Hz tympanograms for admittance, susceptance and conductance main were single-peaked, the percentages of single-peaked type were 62.7%, 77.3% and 62.7%, and the percentages of W-shaped type were 34.6%, 20.9% and 31.8%, had a little three-peaked type. 1000 Hz tympanograms for admittance, susceptance and conductance main were single-peaked, and percentages were 96.4%, 99.1% and 97.3%, and had a little W-shape type but no three-peaked type. There were significant differences between admittance and susceptance, susceptance and conductance in 226 Hz and 678 Hz probe tones tympanogram. There were significant differences between admittance and susceptance, susceptance and conductance, admittance and conductance in 1000 Hz probe tones tympanogram., Conclusion: Multiple-frequency probe tones tympanograms and the normal ranges of admittance, susceptance and conductance of normal newborn infants is obtained, and 1000 Hz probe tone tympanometry is a sensitive test for function of middle ear in newborn infants.