Endolymphatic sac
tumors (ELSTs) are rare neuroectodermal
neoplasms arising within the posterior petrous bone. We present a case of a 21-year-old man who presented with a 6-month history of intermittent morning
headaches,
fatigue,
diplopia, and
gait ataxia. Imaging and surgical pathology identified an
adenocarcinoma of the endolymphatic sac compressing the cerebellum and brain stem. The
tumor and multiple
metastases were treated with surgery, radiation, and radiosurgery. Following insertion of a
ventriculoperitoneal shunt for
hydrocephalus, he developed symptomatic
tension pneumocephalus secondary to radionecrosis of his petrous bone, requiring flap reconstruction and use of a programmable shunt valve complemented by hyperbaric
oxygen (HBO)
therapy. We document here a young patient with a rare
adenocarcinoma of the endolymphatic sac. This case is unique for its initial presentation without any vestibuloauditory symptoms. Metastatic spread of ELSTs is also rare. While
osteoradionecrosis (ORN) of the temporal bone has been reported previously in patients with
nasopharyngeal carcinoma, this is the first time it has been presented in the context of an ELST.
Tension pneumocephalus is a rare complication of skull base ORN. This is the first reported use of a programmable shunt valve and HBO
therapy in the management of
tension pneumocephalus.