The authors present a rare case of fatal cerebral and cerebellar hemorrhagic infarction following an uneventful thoracoscopic microdiscectomy. They hypothesize that this complication was associated with cortical venous thrombosis secondary to intracranial hypotension, which was caused by an unnoticed leak of cerebrospinal fluid (CSF) into the thoracic cavity. Cortical venous thrombosis and intrathoracic CSF were confirmed at autopsy. The former disorder is the most severe manifestation of the pathophysiological mechanism occurring to a lesser degree in patients affected by mild intracranial hypotension, and occurs more frequently in these patients. Intracranial hypotension (of an orthostatic nature or not) must be considered in the differential diagnosis of every patient who complains of headaches after thoracoscopic or open transthoracic microdiscectomy.