The clinical and imaging presentations of the stapical footplate hernia related to inner ear malformation / 中华放射学杂志

ABSTRACT

Objective:To summarize the clinical and imaging presentations of stapical footplate hernia related to inner ear malformation (SFH-Re-IEM).Methods:The clinical and imaging data of 19 patients (24 ears) with SFH-Re-IEM from Shandong Provincial ENT Hospital between June 2014 to June 2022 were retrospectively analyzed. The clinical presentations and headache and the high resolution CT (HRCT) and MRI findings including associated inner ear malformation (IEM) type, internal auditory canal (IAC) malformation, bony defect of the stapical footplate, the extent, margin, density and signal of the herniation cysts, the density and signal of ipsilateral intratympanic, cochlear osseous labyrinthitis were recorded.Results:Among 19 SFH-Re-IEM patients, including 14 males and 5 females, 3 (1, 12) years old. All of the affected ears presented sensorineural or mixed hearing loss, 1 ear for moderate, 7 ears for severe and 16 ears for extremely severe. Besides this, the vertigo in 1 case, otalgia and ear fullness in 2 cases were found, and the others were detected accidentally. Among 24 ears with SFH-Re-IEM, 9 ears (37.5%) consisting with incomplete partition type Ⅰ, 3 ears (12.5%) with common cavity, 7 ears (29.2%) with cochlear aplasia, 3 ears (12.5%) with cochlear dysplasia type Ⅱ, and 2 ears (8.3%) with Mondini deformity were found respectively. Four ears (16.7%) were associated with IAC enlargement and the bony defect of IAC fundus, 19 ears (79.2%) were accompanied with dysplasia in the IAC fundus. In all the 24 ears with SFH-Re-IEM, the focal bony defect of the affected stapical footplate and the hemispherical soft-tissue-density herniating cysts protruding into the tympanium were presented on HRCT, and the herniating cysts presenting the cerebrospinal fluid-like signal with the well-defined margin and the ipsilateral normal tympanium were shown on the MRI hydrographic sequence. Two ears underwent the perilymphaticum gadolinium based on MRI, which demonstrated the hypersignal gadolinium in the perilymphatic space entered into the herniating cysts. Two ears were accompanied with the cochlear osseous labyrinthitis.Conclusion:The ears with IEM-Re-SFH usually present the serious hearing loss. The ipsilateral severe IEM, focal bony defect of the stapical footplate and perilymph herniating are characteristic imaging appearances.