The Association of External and Middle Ear Anomaly and Mandibular Morphology in Congenital Microtia

A new active bone-conduction implant: surgical experiences and audiological outcomes in patients with bilateral congenital microtia

PURPOSE

First-generation bone bridges (BBs) have demonstrated favorable safety and audiological benefits in patients with conductive hearing loss. However, studies on the effects of second-generation BBs are limited, especially among children. In this study, we aimed to explore the surgical and audiological effects of second-generation BBs in patients with bilateral congenital microtia.

METHODS

This single-center prospective study included nine Mandarin-speaking patients with bilateral microtia. All the patients underwent BCI Generation 602 (BCI602; MED-EL, Innsbruck, Austria) implant surgery between September 2021 and June 2023. Audiological and sound localization tests were performed under unaided and BB-aided conditions.

RESULTS

The transmastoid and retrosigmoid sinus approaches were implemented in three and six patients, respectively. No patient underwent preoperative planning, lifts were unnecessary, and no sigmoid sinus or dural compression occurred. The mean function gain at 0.5-4.0 kHz was 28.06 ± 4.55-dB HL. The word recognition scores improved significantly in quiet under the BB aided condition. Signal-to-noise ratio reduction by 10.56 ± 2.30 dB improved the speech reception threshold in noise. Patients fitted with a unilateral BB demonstrated inferior sound source localization after the initial activation.

CONCLUSIONS

Second-generation BBs are safe and effective for patients with bilateral congenital microtia and may be suitable for children with mastoid hypoplasia without preoperative three-dimensional reconstruction.

Correlations Among Clinical Phenotypes, Radiological Examination Indexes, and Hearing Status in Congenital Microtia

Microtia is a congenital malformation of the external ear that often presents with other anatomical abnormalities and ipsilateral hearing loss (HL). The aim of this study was to present the correlation among important phenotypic abnormalities in microtia and their relationship with HL in a clinical population in China. In this study, a retrospective analysis was conducted on 307 patients diagnosed with microtia who visited the Department of Auricular Reconstruction of the Plastic Surgery Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, for surgical auricle reconstruction from April 2021 to April 2022. Standardized classification of ear malformations, craniofacial CT scans, and pure tone audiometric data were collected, and statistical analyses were performed using the rank sum test, Kruskal-Wallis test, and Spearman's rank correlation coefficient. The results showed that group differences between ear malformation and variations in the development of mandible, external auditory canal (EAC), and mastoid pneumatization were statistically significant and each had a positive correlation. Among them, the correlation between development of ear and EAC was the most significant (Ρ=0.72). Besides, the severity of HL (97% were conductive) was positively correlated with ear and EAC dysplasia with or without mandibular hypoplasia. Based on the statistical analysis of the correlation between ear malformation and HL, the authors strongly recommend that facial phenotype reconstruction and hearing improvement of microtia should be considered comprehensively, regardless of whether children with microtia show HL or not, early diagnosis of audiology evaluation and appropriate intervention measures should be implemented.

Temporomandibular Joint and Otitis Media: A Narrative Review of Implications in Etiopathogenesis and Treatment

Otitis media (OM) and its recurring (rAOM), effusive (OME), and chronic forms, represent a frequent clinical challenge. The middle ear, the mandible, and the temporomandibular joint (TMJ) share several embryological and anatomical connections. Despite that, the role of mandibular malposition and TMJ dysfunction is frequently overlooked in the management of otitis media. In this narrative review, we present current evidence supporting the etiopathogenetic role of a dysfunctional stomatognathic system in the onset of OM and the effectiveness of orthognathic treatment in preventing rAOM and OME. In particular, a focus on the influence of TMJ on Eustachian tube function is provided.

Correlation Between Mandible and External Ear in Patients with Treacher-Collins Syndrome

BACKGROUND

Patients with Treacher-Collins syndrome (TCS) are frequently affected by congenital ear deformities. The external ear in patients with TCS tends to have both abnormal morphology and reduced overall volume. Previous studies considered a correlation exists between TCS mandibular skeletal features and external ear volume. The purpose of this study was to assess the external ear volume in patients with TCS 3-dimensionally. Furthermore, this study evaluated the relationship between mandibular morphology, external ear profile, and external ear volume.

METHODS

A total of 36 nonoperated patients with TCS were compared to 39 age- and gender-matched normal controls. Morphologic variables of the mandible and the external ear were compared between TCS group and controls by 3-dimensional cephalometrics. The external ear volume and morphologic variables were analyzed with independent sample T-tests and Pearson correlation coefficient analyses (level of evidence: level III).

RESULTS

The external ear volume was reduced by approximately 50% in patients with TCS compared to controls (P < 0.001). External ear length and width were positively correlated with external ear volume (length: r = 0.809, P < 0.001 on left and r = 0.732, P < 0.001 on right; width: r = 0.518, P = 0.001 on left and r = 0.447, P < 0.010 on right). A negative correlation of right ear inclination angle and external ear volume was shown in patients with TCS (r = -0.396, P = 0.027). However, no correlation was shown for the mandibular anatomic variables.

CONCLUSIONS

Three-dimensional analysis confirmed that external ear volume is significantly reduced in patients with TCS. The external ear dimensions and orientation correlated significantly with ear volume. There was no intrinsic association between the severity of mandibular deformity and external ear volume.

Chorda tympani nerve dysfunction associated with congenital microtia

CONCLUSION

This is the first report to investigate the correlation between ear anomalies related to the development of specific ear structures and chorda tympani dysfunction (CTD) in congenital microtia. CTD is not always consistent with the severity of the ear anomaly or the presence of facial nerve paralysis (FNP).

OBJECTIVES

To investigate the relationship between the severity of ear anomalies and CTD as well as FNP in congenital microtia.

METHODS

A retrospective assessment was performed for all patients with microtia over the period 2010-2016. All ears were graded based on the severity of ear deformity using the Jahrsdoerfer system, based on findings on computed tomography of the temporal bone. Electrogustometry (EGM) was performed to evaluate CTD.

RESULTS

The group included 110 male and 62 female patients. The right ear was the most commonly affected (right 106, left 47). Eighteen patients (10.5%) had abnormal EGM thresholds. The mean (± SD) Jahrsdoerfer scores in the without CTD and positive for CTD groups were 6.53 ± 0.32 and 7.06 ± 0.37, respectively. In terms of sub-total points, there was no significant correlation between anatomic structure and CTD. There was no significant correlation between CTD and the presence of FNP.