AlEnazi Abdulaziz Saud, Alshaiji Abdulaziz, Alenezi Meaad, Al-Sharydah Abdulaziz, Alsuhibani Sari, Alhaidey Ali, Samarah Adnan, AlQahtani Munahi
Department of Otolaryngology -Head and Neck surgery, College of Medicine, King Fahd Hospital of the University, Al-Khobar, Imam Abdul Rahman bin Faisal University, Dammam, P.O Box: 1982, Saudi Arabia.
Department of Radiology, Ministry of Health, Almadinah, Saudi Arabia.
Int J Surg Case Rep. 2022 Jun;95:107109. doi: 10.1016/j.ijscr.2022.107109. Epub 2022 Apr 20.
A narrow duplicated internal auditory canal (IAC) is an extremely rare anomaly, likely associated with congenital sensorineural hearing loss due to aplasia/hypoplasia of the vestibulocochlear nerve or the cochlear branch alone. We aimed to review our experience with IAC duplication, describe its clinical characteristics, and present a literature review.
Our Otology database was searched for children who showed duplication of the IAC. Clinical characteristics of two children with bilateral duplication of the IAC are described. Data regarding clinical history, auditory assessment, magnetic resonance imaging (MRI), and computed tomography (CT) were collected and analyzed. The separated, accessory bony canals were demonstrated on high-resolution CT scans, and the nerves were demonstrated on MRI.
To date, a few cases of narrow duplicate IAC have been reported in the literature, Approximately 20% of patients with congenital SNHL are found to show inner-ear bony abnormalities on CT, but much uncertainty still exists about the mechanism underlying IAC stenosis. Imaging findings of the temporal bone in our case series demonstrated asymmetrical narrowing of both IACs, there is no clear evidence in the literature supporting the predominance of one side over the other. In our series, facial nerve function was intact bilaterally. As for our cases, both patients were enrolled in a single-sided deafness evaluation for a trial of options such as BAHA, CROS, cochlear implants, and other non-implantable hearing aids. Furthermore, addressing the important factors will optimize the outcomes including surgery at early age to optimize neural plasticity, with intense long-term therapy.
Congenital duplication of the IAC likely convoying sensorineural hearing loss due to aplasia/hypoplasia of the vestibulocochlear nerve. Early diagnosis and intervention are essential to optimize patient outcomes.
狭窄的重复内耳道（IAC）是一种极其罕见的异常情况，可能与先天性感音神经性听力损失有关，原因是前庭蜗神经或仅蜗神经分支发育不全/发育不良。我们旨在回顾我们在IAC重复方面的经验，描述其临床特征，并进行文献综述。
在我们的耳科学数据库中搜索显示IAC重复的儿童。描述了两名双侧IAC重复儿童的临床特征。收集并分析了有关临床病史、听力评估、磁共振成像（MRI）和计算机断层扫描（CT）的数据。在高分辨率CT扫描上显示出分离的副骨管，在MRI上显示出神经。
迄今为止，文献中已报道了少数狭窄重复IAC的病例。大约20%的先天性感音神经性听力损失患者在CT上发现内耳骨质异常，但IAC狭窄的潜在机制仍存在很多不确定性。我们病例系列中的颞骨影像学表现显示双侧IAC不对称狭窄，文献中没有明确证据支持一侧比另一侧更占优势。在我们的系列中，双侧面神经功能均完好。就我们的病例而言，两名患者都参加了单侧耳聋评估，以试验如骨锚式助听器（BAHA）、对侧信号互传助听器（CROS）、人工耳蜗和其他非植入式助听器等选项。此外，解决重要因素将优化结果，包括在早期进行手术以优化神经可塑性，并进行强化的长期治疗。
IAC先天性重复可能因前庭蜗神经发育不全/发育不良而伴有感音神经性听力损失。早期诊断和干预对于优化患者预后至关重要。
