Cochlear incomplete partition type III anomaly (IP-III), also referred as X-linked deafness type 2 or X-linked stapes gusher syndrome, is a rare congenital cause of severe progressive mixed hearing loss affecting mainly male patients. It has characteristic radiological features, consisting of, a corkscrew appearance of the cochlea due to dilatation of the internal auditory canal (IAC) and the direct communication between the IAC and the cochlea secondary to the absent bony plate between the two cavities (lamina cribrosa). Preoperative diagnosis of IP-III facilitates the surgeon in avoiding unnecessary stapes surgery and possible complications of cochlear implantation, such as perilymph gushing during cochleostomy and misplacement of the electrode into the internal auditory meatus, which can lead to further hearing loss. Furthermore, the preoperative HRCT images facilitate the surgeon in sizing and selecting of the most appropriate implant type for the procedure.

Cochlear incomplete partition type III anomaly (IP-III), also referred as X-linked deafness type 2 or X-linked stapes gusher syndrome, is a rare congenital cause of severe progressive mixed hearing loss affecting mainly male patients. It has characteristic radiological features, consisting of, a cor...