A Case of Bilateral Congenital Aural Stenosis with Down Syndrome Underwent Canalplasty with Underwater Transcanal Endoscopic Ear Surgery.

Congenital aural stenosis (CAS) sometimes can be a risk for external auditory canal (EAC) cholesteatoma and may require surgical treatment. We report a child of Down syndrome with bilateral CAS who underwent bilateral canalplasty with underwater transcanal endoscopic ear surgery (TEES). Case Report: A 12-year-old boy with bilateral EAC stenosis, in whom tympanostomy tube insertion for secretory otitis media (SOM) had failed at 5 and 8 years of age, was referred to our department for surgical treatment. The bilateral EACs were so narrow and curved that the tym-panic membranes could not be entirely observed. The osseous EAC (OEAC) diameters were measured on sagittal computed tomography (CT) images with ImageJ. The minimum Feret diameter was 3.05 mm in the right ear and 2.98 mm in the left ear. Bilateral canalplasty with underwater TEES and tympanostomy tube insertion was performed for CAS complicated by SOM. One month after surgery, bilateral EACs were well-epithe-lialized and the tympanic membranes were easily observed. Canalplasty with underwater TEES is minimally invasive, secure, and provides a clear surgical field, and is therefore a useful option for children with EAC stenosis.