A flexible tube with a sensor at the distal end intended to be surgically inserted through the skull for short-term (= 30 days) access to the ventricular and/or parenchymal areas of the brain to measure intracranial parameters [e.g., intracranial pressure (ICP), temperature, partial pressure of oxygen (pO2)]; it may in addition be intended for cerebrospinal fluid (CSF) drainage and/or infusion of materials (e.g., chemotherapeutic agents, radioisotopes). It may include accessory devices intended to facilitate catheter introduction, stabilization, and/or fluid collection/infusion (e.g., stylet, bolts, drills, drainage/infusion port/reservoir). This is a single-use device.