[Three-phase infusion test]

A new CSF circulation diagnostic procedure is presented. The method is called three-phase infusion test. In phase I the CSF absorption mechanisms were tested within ICP range below 20 mmHg and then the infusion rate of 0.06 ml/min was applied. In phase II the high infusion rate (0.3 ml/min) was used and high ICP increase occurred. This part of the study provided data concerning the ability of alternative CSF outflow routes. In phase III again low infusion rate (0.06 ml/min) was applied. The obtained CSF outflow data in phase III were significantly lower than in phase I. This is the so called persistent outflow facilitation phenomenon. The method described, covering different mechanisms of CSF absorption, enables the complex evaluation of CSF outflow sufficiency.