{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,5,27]],"date-time":"2026-05-27T23:07:30Z","timestamp":1779923250437,"version":"3.53.1"},"reference-count":26,"publisher":"Georg Thieme Verlag KG","issue":"06","content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Rofo"],"published-print":{"date-parts":[[2026,6]]},"abstract":"<jats:title>Abstract<\/jats:title>\n                  <jats:p>Malformations of the internal auditory canal (IAC) are rare. They can present as a narrowing of the canal due to aplasia or hypoplasia of the vestibulocochlear nerve, complete atresia, or even a doubling of the IAC. The aim of our study is to provide a comprehensive overview of the different types of IAC anomalies and to provide a classification based on radiological findings and their relation to syndromes and\/or inner\/middle ear anomalies. In addition, IAC malformations will be explained in a putative phylogenetic context.<\/jats:p>\n                  <jats:p>All patients who underwent pre-interventional imaging between 1995 to 2024 for evaluation of a hearing implant in domo with an inner ear malformation were included in the present retrospective study. The available imaging data, i.e. high resolution computed tomography (HRCT) or cone beam CT (CBCT) of the temporal bone and supplementary MR of the temporal bone, were reviewed independently by two neuroradiologists. Malformations of the IAC and concomitant malformations of the middle and inner ear were recorded. Demographic and clinical data were also collected. Based on the data and information obtained, a radiological classification of the different IAC malformations was provided.<\/jats:p>\n                  <jats:p>A total of 36 patients (55 affected ears) were included in the analysis. The majority of the patients were female (75%). The mean age was 6.3 \u00b1 9.4 years (mean \u00b1 std). A syndromic disease was present in 28% of the patients. Due to severe hearing loss, a total of 48% of patients received a hearing system. Based on the radiological findings, we performed the following typing: Type I \u2013 Narrow IAC; Type II \u2013 Atresia with isolated facial nerve canal; Type III \u2013 Double IAC with\/without atresia, Type IV \u2013 Complete atresia. In descending order, the frequency of these malformations of the IAC in our cohort was distributed as follows: Type III \u2013 Double (n= 29, 52.7%), Type I \u2013 Narrow (n=15, 27.3%), Type IV \u2013 Complete atresia (n=4, 7.3%), Type II \u2013 Atresia with isolated facial nerve canal (n=7, 12.7%).<\/jats:p>\n                  <jats:p>Since hypoplastic IAC may be associated with hypoplastic or absent cochlear nerve and sensorineural hearing loss, radiological assessment of the IAC is of critical importance in the evaluation of patients with severe sensorineural hearing loss undergoing cochlear implantation. Accurate analysis of the imaging data and understanding the complexity of the malformations are of great importance in assessing the expected benefits prior to cochlear implantation.<\/jats:p>","DOI":"10.1055\/a-2699-9904","type":"journal-article","created":{"date-parts":[[2025,9,29]],"date-time":"2025-09-29T22:57:03Z","timestamp":1759186623000},"page":"763-773","source":"Crossref","is-referenced-by-count":0,"title":["Radiological Characterization of Malformations of the Internal Auditory Canal"],"prefix":"10.1055","volume":"198","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-6965-8906","authenticated-orcid":false,"given":"Katja","family":"D\u00f6ring","sequence":"additional","affiliation":[{"name":"Hannover Medical School, NDS, Germany","place":["Hanover"],"department":["Department of Diagnostic and Interventional Neuroradiology"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Rolf","family":"Salcher","sequence":"additional","affiliation":[{"name":"Hannover Medical School, NDS, Germany","place":["Hanover"],"department":["Department of Otorhinolaryngology"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-4405-6781","authenticated-orcid":false,"given":"Heinrich","family":"Lanfermann","sequence":"additional","affiliation":[{"name":"Hannover Medical School, NDS, Germany","place":["Hanover"],"department":["Department of Diagnostic and Interventional Neuroradiology"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Thomas","family":"Lenarz","sequence":"additional","affiliation":[{"name":"Hannover Medical School, NDS, Germany","place":["Hanover"],"department":["Department of Otorhinolaryngology"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Athanasia","family":"Warnecke","sequence":"additional","affiliation":[{"name":"Hannover Medical School, NDS, Germany","place":["Hanover"],"department":["Department of Otorhinolaryngology"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Anja","family":"Giesemann","sequence":"additional","affiliation":[{"name":"Hannover Medical School, NDS, Germany","place":["Hanover"],"department":["Department of Diagnostic and Interventional Neuroradiology"]}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"194","published-online":{"date-parts":[[2025,9,29]]},"reference":[{"key":"ref1","doi-asserted-by":"publisher","first-page":"199","DOI":"10.5152\/iao.2016.1440","article-title":"A challenge for cochlear implantation: Duplicated internal auditory canal","volume":"12","author":"A Binneto\u011flu","year":"2016","journal-title":"J Int Adv Otol"},{"key":"ref2","doi-asserted-by":"publisher","first-page":"823","DOI":"10.3348\/kjr.2018.0065","article-title":"Duplicated internal auditory canal: High-resolution CT and MRI findings","volume":"20","author":"L Wang","year":"2019","journal-title":"Korean J 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