Intracranial hypotension syndrome in a patient due to suboccipital craniectomy secondary to Chiari type malformation

Intracranial hypotension syndrome (IHS) is a rare disorder characterized by a decrease in cerebrospinal fluid pressure to less than 60 mm H₂O. The syndrome is associated with occipital headache radiating to the frontal and temporal zones. The current clinical case describes the manifestation of IHS in a twenty-five year old female with a history of suboccipital craniectomy due to Chiari I malformation nine years earlier. The patient was admitted to the hospital complaining about postural, mainly occipital, headache during the last three months, aggravated by being in an upright position. The magnetic resonance imaging (MRI) revealed engorgement of the dural venous sinuses, significant enlargement of the pituitary gland and download displacement or sagging of the brain with effacement of the perichiasmatic cisterns and the prepontine cistern, while the spinal T2W MRI revealed a 7 mm × 2.5 mm dural defect with an extradural cerebrospinal fluid collection at the dorsal soft tissues of the cervical spine. The previous imaging did not reveal subdural effusions.