Foramen Tympanicum (Foramen of Huschke) as a Cause of Unexplained Spontaneous Otorrhea: A Case Report

The foramen of Huschke or foramen tympanicum is a developmental defect in the bony part of the external auditory meatus. It occurs due to incomplete obliteration of the tympanic canal and the persistence of openings along the canal. This leads to the presence of a salivary fistula and the most common symptoms of the condition are otalgia, otorrhea, and hearing loss. We report a case of a 69-year-old female patient who presented to the ENT with symptoms of watery discharge from the left ear for 12 years. In the last two weeks, pain and itching appeared. Otoscopy showed the presence of a clear fluid in the external auditory meatus with a normal tympanic membrane. Biochemical analysis of the fluid proved the presence of amylase. Computed tomography showed a fistula between the parotid gland and the external ear canal. The diagnosis of the persistent foramen of Huschke remains difficult due to the fact that it could mimic many other conditions. The otalgia and otorrhea are symptoms that suggest a very wide differential diagnosis. Misdiagnosis and inappropriate treatment are common.