Spontaneous intracranial hypotension: morphological findings and CSF flow dynamics studied by MRI.

We report on a case of spontaneous intracranial hypotension (SIH) presenting with classic MR findings, such as diffuse smooth thickening and intense contrast enhancement of the dura matter, increased size of the pituitary gland and downward displacement of the brain. In this case an engorgement of the cavernous sinuses is reported as an additional imaging finding of SIH. Moreover, phase-contrast MR study of the CSF flow dynamics revealed at the level of the aqueduct a decrease of the systolic and diastolic flow volume of CSF. A normalization of the flow volume was observed when SIH subsided.