1110 Hypersomnolence following frontal lobectomy

Abstract

Introduction: Central nervous system (CNS) lesions in the frontal lobe has been implicated in sleep disorders, particularly hypersomnia. A study demonstrated that Parkinson's patients with excessive daytime sleepiness (EDS) exhibited atrophy of the frontal lobe whereas patients without EDS did not have these architectural changes. Another study demonstrated individuals with idiopathic hypersomnia may be correlated with lower cerebral blood flow in the medial prefrontal cortex compared to healthy individuals. Here we have a case of hypersomnolence after resection of right frontal lobe arteriovenous malformation (AVM). Report of Case: This is a case of a 21-year-old active duty male identified to have AVM in the right frontal lobe after an isolated seizure episode. After being initiated on levetiracetam he underwent a series of elective embolization and then a resection of the right anterior frontal AVM. The operation was complicated by hemorrhage that followed a prolonged ICU course; however, recovery was successful. He presented to the sleep clinic 10 months post-op complaining of excessive daytime sleepiness that was not present prior to the surgery. His overnight polysomnography was not suggestive for obstructive sleep apnea; however, he exhibited decreased stage N3 and increased stage REM with sleep onset latency of 18 minutes and REM latency of 190 minutes. A Mean Sleep Latency Test was performed resulting in an average sleep latency of 0.9 minutes with no sleep-onset REM periods (SOREMP). His two-week actigraphy displayed an average sleep time of 10 hours and 35 min per day. He was diagnosed with hypersomnia due to medical disorder (secondary to CNS lesion) with long sleep time. The patient was initiated on stimulant therapy with modafinil 100mg per day. Conclusion: CNS injuries may exhibit excessive daytime sleepiness. In the event of traumatic brain injuries with changes to frontal lobe architecture, a high index of suspicion of sleep disorders should include hypersomnolence.