To compare the benefits of physiological saline solution and artificial cerebrospinal fluid (CSF) as perfusates, we investigated 12 patients with presumed symptomatic aqueductal stenosis by clinical course and CSF analysis. In all patients, endoneurosurgical third ventriculostomy and cine magnetic resonance imaging confirmed the patency of ventriculostomy. After endoneurosurgery, patients who received the saline solution experienced high fever, headaches, and elevated cell count in lumbar CSF. Saline solution provoked a striking inflammatory reaction in the CSF. In contrast, the artificial CSF reduced these conditions to a minimum. Artificial CSF used as a physiological perfusate during endoneurosurgery can suppress host reactions within the CSF pathway and is also available for routine neurosurgical procedures.