HYDROCEPHALUS - OBLITERATED PERIMESENCEPHALIC CISTERNS AND THE DANGEROF SUDDEN-DEATH

Objective: We report a possible risk factor which could identify patie nts with chronic hydrocephalus who are at risk for sudden death. Metho ds: A retrospective review of medical records and computed tomographic (CT) scans was conducted on three patients with chronic hydrocephalus who suffered acute cardiorespiratory arrest without those signs which are normally associated with a progressive worsening of hydrocephalus . Results: All three of these patients were awake and communicative sh ortly before the life threatening or terminal event. All had experienc ed some recent worsening of neurologic signs or symptoms, but none had shown a progressive impairment of consciousness or major neurologic d ecline ordinarily associated with life threatening elevation of intrac ranial pressure. Absence of the perimesencephalic cisterns on head CT scans done prior to or just after the life threatening event was the o nly new radiologic finding common to all these patients. Conclusions: The absence of the perimesencephalic cisterns in an awake and alert pa tient with severe hydrocephalus indicates that the patient may be at r isk for neurogenic cardiorespiratory failure. In such cases, (especial ly when there has been a recent, albeit mild, change in neurologic sig ns or symptoms), the neurologist should urge emergency ventriculostomy or shunting for the hydrocephalus.