Langerhans Cell Histiocytosis of the Temporal Bone with Otic Capsule Involvement.

INTRODUCTION: This study is conducted to demonstrate that destructive lesions of the otic capsule by Langerhans cell histiocytosis (LCH) causing both radiographic and audiologic findings can be completely reversed with adequate treatment. Retrospective case review and analysis of clinical and imaging data were obtained as part of the diagnosis and treatment of patients with LCH of the temporal bone.

METHODS: With Institutional Review Board (IRB) approval, cases of LCH involving the temporal bone were searched for within the institutional databases. Criteria for inclusion was histologic diagnosis of LCH and pretreatment computed tomography (CT) demonstrating temporal bone and/or otic capsule involvement and posttreatment follow-up CT/magnetic resonance imaging (MRI) scans obtained at least 6 months after starting treatment.

RESULTS: We report eight cases of LCH of the temporal bone with three demonstrating otic capsule involvement radiographically and/or clinically. Review of posttreatment imaging revealed all three patients had complete restoration of the bony labyrinthine architecture and near or complete restoration of their hearing.

CONCLUSIONS: Though LCH of the temporal bone is a common site within the spectrum of the disease, involvement of the otic capsule remains rare. Here, we report the largest series of otic capsule involvement by LCH and investigate whether both architecture and hearing are recovered with appropriate treatment. Lastly, restoration of the bony architecture of the labyrinth suggests the mechanism of LCH is demineralization and not ablative.