Study of hearing features of Congenital Malformation of the Middle and Outer Ear (CMMOE)

Background: There is no study on the hearing features of congenital malformation of middle and outer ears (CMMOE), including classification, grades, and frequency characteristics, which play a decisive role in the selection of precise hearing solutions for patients. Aims/Objectives: To analyze the hearing features of CMMOE and provide guidance for clinical practice.Material and Methods: 298 cases (351 ears) with CMMOE were retrospectively analyzed for the features of 0.5 ∼ 4KHz pure tone hearing, including the classification, grades and frequency characteristics. Results: We observed conductive deafness in 84.3% (296/351), mixed deafness in 15.7% (55/351), and 0% (0/351) sensorineural deafness. Grades measured by average Air Conduction Thresholds (ACT) of pure tone: Mild deafness (26-40dB HL) 0.6% (2/351), moderate deafness (41-55dB HL) 10.3% (36/351), moderate to severe deafness (56-70dB HL) 46.1%(162/351), severe deafness (71-90dB HL) 39.9%(140/351), extremely severe deafness (> 90 dB HL) 3.1%(11/351). The average ACT of 296 ears conductive deafness was 67 ± 10 dB HL, of which 56-80dB HL accounted for 78.1% (274/351). In 55 ears with mixed deafness, 32 ears (32/55 = 58.2%) increased Bone Conduction Threshold (BCT) at a single frequency, and out of 32 ears, 31ears (31/55 = 56.4%) ≤40dB HL, 25(25/32 = 78.1%) ears at 2KHz. In 55 ears with mixed deafness, 87.3% (48/55) increased BCT at 2KHz, and the average BCT was 35 ± 10dB HL. Conclusions and Significance: CMMOE result mainly in conductive deafness, moderate to severe and severe deafness. In mixed deafness, the BCT increased mainly at a single frequency, 2KHz and ≤40dB HL. These data suggest that bone-conductive hearing devices are a good solution for CMMOE hearing impairment.

X-linked Alport syndrome: pathogenic variant features and further auditory genotype-phenotype correlations in males

OBJECTIVE

To analyze the clinical audiological characteristics of X-Linked Alport syndrome (XLAS) in males and their relationships with genotypes.

METHODS

The clinical data of 87 male patients with AS were reviewed. Hearing levels were evaluated using pure tone audiometry (PTA) testing, acoustic immittance, and otoacoustic emissions (OAE) testing. The genotypes of COL4A5 and the pathogenic variants were analyzed. The relationships between auditory phenotypes and genotypes were analyzed.

RESULTS

Among the 87 patients, the number of patients with normal hearing and hearing loss were 32 and 55, respectively. In all cases, the hearing loss was characterized as bilateral symmetrical sensorineural deafness. Majority of the patients had mild-to-moderate hearing loss. Hearing loss usually started in the middle frequency range and gradually affected high frequencies, at school age and gradually increased with increasing age. However, it maintained a relatively steady level of 50-60 dB HL during the teenage years. The audiometric curves included groove-type in 51 cases (92.73%). Patients were identified to have 60 different COL4A5 pathogenic variants. Of the 49 patients who were followed-up for more than 2 years, 28 cases presented a decreasing trend in the hearing level of about 5 dB per year. The degree of hearing loss was positively correlated with gene mutation type and renal function.

CONCLUSIONS

Hearing loss in males with XLAS is symmetrical sensorineural, and progressive with increasing age. There is a significant correlation between the degree of hearing loss and genotype, renal function, and age.