岡野 高之

This article describes an extremely rare case of pediatric congenital external auditory canal cholesteatoma (EACC) that extended beyond the external auditory canal. A five-year-old girl presented with progressive swelling in the posterior wall of the left external auditory canal. Computed tomography of the temporal bone revealed a well-defined round mass that compressed and eroded the posterior canal wall without invasion of the mastoid tegmen, sigmoid sinus, or tympanic membrane. Surgical exploration via a retroauricular approach confirmed the presence of a cholesteatoma extending from the external auditory canal to the mastoid cavity; furthermore, complete excision was achieved. There has been a recent increase in the number of reported EACC pediatric cases, especially in East Asia. However, few studies have clearly distinguished congenital and acquired forms, which could be largely attributed to challenges in differential diagnosis, particularly when lesions extend beyond the canal. Based on our findings, we propose radiological and clinical features that may facilitate differentiation between congenital and acquired EACC, even in advanced-stage cases. This article highlights the importance of accurate classification for elucidation of the pathogenesis of EACC and optimization of surgical decision-making in pediatric patients with EACC.

BACKGROUND/OBJECTIVES: The OTOG gene is responsible for autosomal recessive non-syndromic sensorineural hearing loss and is assigned as DFNB18B. To date, 44 causative OTOG variants have been reported to cause non-syndromic hearing loss. However, the detailed clinical features for OTOG-associated hearing loss remain unclear. METHODS: In this study, we analyzed 7065 patients with non-syndromic hearing loss (mean age 26.4 ± 22.9 years, 2988 male, 3855 female, and 222 without gender information) using massively parallel DNA sequencing for 158 target deafness genes. We identified the patients with biallelic OTOG variants and summarized the clinical characteristics. RESULTS: Among the 7065 patients, we identified 14 possibly disease-causing OTOG variants in 26 probands, with 13 of the 14 variants regarded as novel. Patients with OTOG-associated hearing loss mostly showed congenital or childhood-onset hearing loss. They were considered to show non-progressive, mild-to-moderate hearing loss. There were no symptoms that accompanied the hearing loss in OTOG-associated hearing loss patients. CONCLUSIONS: We confirmed non-progressive, mild-to-moderate hearing loss as the clinical characteristics of OTOG-associated hearing loss. These findings will contribute to a better understanding of the clinical features of OTOG-associated HL and will be useful in clinical practice.

OBJECTIVE: To determine whether the combination of the pharyngeal tonsil grade and palatine tonsil grade results in differences in the apnea-hypopnea index (AHI) and to determine whether each parameter separately (pharyngeal tonsil grade and palatine tonsil grade) results in differences in severe obstructive sleep apnea (OSA). METHODS: This cross-sectional study involved 107 children (mean age, 7.2 years; range, 4-12 years) suspected of having OSA because of snoring or sleep-related complaints. The patients underwent polysomnography, and their palatine and pharyngeal tonsils were graded. RESULTS: In examining whether the palatine tonsils and pharyngeal tonsils could be risk factors for severe OSA, the adjusted odds ratios were 4.42 for palatine tonsil grade 4 versus 1-3 and 10.40 for pharyngeal tonsil grade 4 versus 1-3; both were highly statistically significant. We also found that the AHI when both the pharyngeal and palatine tonsils were grade 4 was higher than the AHI expected for the pharyngeal and palatine tonsils alone. CONCLUSIONS: The combination of grade 4 pharyngeal tonsils and grade 4 palatine tonsils resulted in an AHI much higher than the AHI of other combinations (pharyngeal tonsils grades 1-3 and 4, palatine tonsils grades 1-3 and 4). We believe that grade 4 pharyngeal tonsils and grade 4 palatine tonsils have a great influence on severe OSA and that grade 4 pharyngeal tonsils increase the AHI.

OBJECTIVES: The aim of this study was to evaluate the safety and efficacy of microdebrider adenoidectomy on sleep-disordered breathing among pediatric patients with OSA. METHODS: In the microdebrider group (Group I), there were 30 Japanese OSA patients consisting of 26 boys and 4 girls. For comparison, we had 15 children (13 boys and 2 girls) who underwent classical adenoidectomy (Group II). Patients in Group I were selected from a pool of 95 pediatric Japanese OSA patients and were matched by age, preoperative AHI, and Kaup index with those in Group II.Parameters such as the amount of residual adenoid tissue, bleeding, duration of the procedure, and sleep-related metrics were compared between the two groups. RESULTS: A significant improvement in postoperative AHI was observed in Group I (p<0.05). The prevalence of AHI <1 was significantly higher in Group I compared with Group II (p<0.05). Additionally, the amount of postoperative residual adenoid was significantly less in Group I (3/30 of Grade 3 and 4 adenoid size) than in Group II (7/15, p<0.05). Furthermore, a reduction in postoperative AHI was proportionally associated with a decrease in residual adenoid. CONCLUSIONS: The newly developed microdebrider adenoidectomy technique for pediatric OSA patients with adenotonsillar hypertrophy demonstrated greater accuracy and efficacy in ameliorating sleep apnea symptoms compared with the standard adenoidectomy approach.