ICP readings will be recorded from both the invasive and HeadSense non-invasive ICP monitor for an aggregate of 30 minutes. During the recording sessions, a webcam will take periodic snapshots of the ICP monitor and/or bedside monitor picturing the ICP values and other clinical parameters that are displayed on screen, with a focus on blood pressure and heart rate (HR). Recording sessions will be done until an aggregate of at least 30 minutes of data are collected, depending on the patient's clinical condition. Recording sessions may be repeated over several days until the 30 minute target is reached.