Reversible obstructive hydrocephalus from hypertensive encephalopathy

Background: Diffuse edema involving the posterior fossa may be seen with hypertensive encephalopathy and has rarely been reported to cause hydrocephalus. We present three such cases and review the literature to better delineate this uniquely reversible syndrome. Methods: Case reports and review of literature. Results: Three patients with hypertensive encephalopathy presented to our institutions with clinical and radiographic features of obstructive hydrocephalus associated with brainstem and cerebellar edema. This required transient external drainage of cerebrospinal fluid (CSF) in two of the three patients. However, with recognition of this unusual syndrome and aggressive management of elevated blood pressure, both edema and hydrocephalus resolved. All patients made complete recoveries and did not require permanent CSF shunting. A review of the literature yielded 15 additional case reports describing reversible obstructive hydrocephalus related to hypertensive encephalopathy. All had mean arterial pressures above 130 mmHg and presented primarily with altered mental status. While half required ventriculostomy, only one required shunting. Excluding a patient who died from sepsis, all recovered neurologically once blood pressure was controlled. Conclusion: It is imperative to recognize such cases where hypertension causes edema within the posterior fossa resulting in secondary hydrocephalus. Focusing management on lowering blood pressure avoids unnecessary or prolonged CSF diversion.