64-year-old woman with a personal history of diabetes mellitus, arterial hypertension and atrial fibrillation anticoagulated with acenocoumarol. She was seen at the outpatient clinic for a clinical picture of inability to ambulate and occasional urinary incontinence, with impairment of higher functions and emotional lability. Neuroimaging studies showed tetraventricular hydrocephalus. Suspicion of CAH led to the placement of a DLE as a diagnostic test. After replacing acenocoumarol with low molecular weight heparin a few weeks earlier, the DLE was placed. During the transfer of the patient from the operating theatre to the hospital ward, the drain was accidentally kept open. Six hours after placement, after draining 240 ml of CSF, the patient began to experience headaches, nausea, vomiting and sweating, which were initially attributed to intracranial hypotension. At no time did the level of consciousness deteriorate. In view of the intensity of the symptoms, an urgent cranial CT scan was performed which showed the presence of a haematoma in the left cerebellar vermis and hemisphere, with subarachnoid bleeding on the upper surface of the cerebellum and in the cerebellar folia. The DLE was removed immediately and, given the patient's good clinical condition, it was decided to follow conservative treatment, with good clinical evolution. Neuroimaging studies (MRI and cerebral angiography) ruled out the existence of underlying pathology.

The patient recovered to her previous state. Subsequently, a ventriculoperitoneal shunt was implanted, with great clinical improvement.