De novo sensorineural hearing loss sequelae of narrow, duplicated internal auditory canal: Case series and literature review

• Published in: International journal of surgery case reports 2022-06, Vol.95, p.107109-107109, Article 107109
• Main Authors: AlEnazi, Abdulaziz Saud, Alshaiji, Abdulaziz, Alenezi, Meaad, Al-Sharydah, Abdulaziz, Alsuhibani, Sari, Alhaidey, Ali, Samarah, Adnan, AlQahtani, Munahi
• Format: Article
• Language: English
• Subjects: Case Series; Congenital; Duplication; Hearing loss; Internal auditory canal; Sensorineural
• ISSN: 2210-2612; 2210-2612
• DOI: 10.1016/j.ijscr.2022.107109

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.5 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. •Duplication of the internal auditory canal is a very rare entity can be associated with sensorineural hearing loss owing to aplasia/hypoplasia of the vestibulocochlear nerve.•Discuse the presentation “Duplication of the internal auditory canal” where finding demonstrate a normal function of facial nerve in two cases with profound SNHL.•Discuss the challenges encountered in the diagnosis and treatment of this condition.•Sumariey of literature Finding of Duplication of the internal auditory canal.