Resolution of obstructive sleep apnea with epilepsy surgery? Expanding the relationship between sleep and epilepsy.

Recent studies suggest a higher than expected prevalence of obstructive sleep apnea (OSA) in patients with refractory epilepsy. In some cases, treatment of OSA improves seizure control. We report a case in which clinically significant OSA disappeared after left frontal lobe resection that produced a near seizure free state. This occurred in the absence of the usual factors, such as weight or medication change or variation in polysomnography (PSG) recording methodology, that often confound the comparison of sequential PSGs over time. Our patient underwent PSG with 18-channel EEG recording pre- and postoperatively using standardized scoring techniques. Baseline testing revealed an apnea-hypopnea index (AHI) of 24 with severe oxygen desaturations reaching a nadir of 62%. Postoperative testing found both the AHI and oxygen saturation normalized as well as a marked reduction in spike rate. We hypothesize that the pathophysiology of OSA in patients with epilepsy may be impacted by frequent, extensive interictal epileptiform discharges (IEDs) and/or seizures altering upper airway control during sleep.