Pearls and oy-sters: reversible Ondine's curse in a case of lateral medullary infarction.

Ondine's curse is an eponym that refers to central alveolar apnea/hypopnea observed among patients with acquired or congenital brainstem disorders. This condition results in loss of automatic and/or voluntary respiration with characteristic polysomnographic finding of impaired ventilator responses to hypercapnia and sleep apnea, which are more pronounced during non-REM sleep, less in REM sleep, and least during wakefulness.