Kamakura Takefumi, Lee Daniel J, Herrmann Barbara S, Nadol Joseph B
Otopathology Laboratory, Department of Otolaryngology, Massachusetts Eye and Ear Infirmary, Boston, MA, USA.
Audiol Neurootol. 2017;22(2):116-123. doi: 10.1159/000477534. Epub 2017 Aug 24.
The Cogan syndrome is a rare disorder characterized by nonsyphilitic interstitial keratitis and audiovestibular symptoms. Profound sensorineural hearing loss has been reported in approximately half of the patients with the Cogan syndrome resulting in candidacy for cochlear implantation in some patients. The current study is the first histopathologic report on the temporal bones of a patient with the Cogan syndrome who during life underwent bilateral cochlear implantation. Preoperative MRI revealed tissue with high density in the basal turns of both cochleae and both vestibular systems consistent with fibrous tissue due to labyrinthitis. Histopathology demonstrated fibrous tissue and new bone formation within the cochlea and vestibular apparatus, worse on the right. Severe degeneration of the vestibular end organs and new bone formation in the labyrinth were seen more on the right than on the left. Although severe bilateral degeneration of the spiral ganglion neurons was seen, especially on the right, the postoperative word discrimination score was between 50 and 60% bilaterally. Impedance measures were generally higher in the right ear, possibly related to more fibrous tissue and new bone found in the scala tympani on the right side.
科根综合征是一种罕见疾病，其特征为非梅毒性间质性角膜炎和视听前庭症状。据报道，约半数科根综合征患者会出现重度感音神经性听力损失，部分患者因此符合人工耳蜗植入标准。本研究是首例关于一名生前接受双侧人工耳蜗植入的科根综合征患者颞骨的组织病理学报告。术前磁共振成像显示双侧耳蜗基底转及双侧前庭系统存在高密度组织，符合迷路炎所致的纤维组织表现。组织病理学显示耳蜗和前庭器内有纤维组织及新骨形成，右侧情况更严重。右侧前庭终器的严重退变及迷路内新骨形成比左侧更明显。尽管双侧螺旋神经节神经元均有严重退变，尤其是右侧，但术后双侧言语辨别得分在50%至60%之间。阻抗测量结果通常右侧耳更高，这可能与右侧鼓阶内发现更多纤维组织和新骨有关。
