Large anterior skull base lesions in patients presenting with obstructive sleep apnea. Report of two cases and review of the literature.

Abstract

Patients with sleep apnea often are treated by sleep disorder specialists and are studied in a sleep laboratory. The authors present two such patients who ultimately were found to harbor large benign anterior skull base lesions that caused their obstructive sleep apnea (OSA). The first patient had a massive pituitary tumor and had undergone a tracheostomy before the lesion was diagnosed. The second patient had a large frontoethmoidal encephalocele that was diagnosed at the same time as a recommendation for continuous positive airway pressure therapy was being considered. Such therapy in the presence of an encephalocele can be dangerous and even fatal. Although there are case reports of tumors causing OSA, nearly all of these lesions have been large pharyngeal lipomas (some of which were palpable in the neck during physical examination) or growth hormone-secreting pituitary adenomas. The patients reported here were completely unaware of the presence of these large lesions until imaging studies and/or nasal endoscopy were performed. These cases illustrate the need to perform nasopharyngeal endoscopy and also to obtain magnetic resonance images of the head before prescribing therapy for OSA. Neurosurgeons must be aware that large skull base lesions sometimes present only with OSA.