CSF otorrhea complicating osteoradionecrosis of the temporal bone

Osteoradionecrosis of the temporal bone is a well-recognized complication of radiotherapy for head and neck malignancy. There are two mechanisms by which this condition can produce damage to nearby structures and even result in death. Osteoradionecrosis may (1) predispose the patient to an aggressive or chronic infectious process, or (2) cause destruction of tissue by direct necrosis. A review of the literature failed to disclose a cause of CSF otorrhea complicating osteoradionecrosis of the temporal bone. This paper describes a case of skull base osteoradionecrosis, including necrosis of the tympanic membrane, associated with CSF otorrhea. Successful control of this complication was achieved using a translabyrinthine approach to locate the fistula, which originated from the internal auditory canal and was discharging through the middle ear via the oval window. The leak was sealed, the resultant mastoid cavity was obliterated by rotation of a temporalis muscle flap, and the external auditory canal was closed by the Fisch technique.