Noninvasive method to measure intracranial and effective cerebral outflow pressure

A method for detecting and measuring increased global or local intracranial pressure within a subject cranium, comprising:

• using noninvasive spectroscopy measuring means, creating and investigating a first light pathway through a portion of extracranial tissue, including blood pathways, surrounding the subject cranium and a second light pathway through a portion of intracranial tissue, including blood pathways, within the subject cranium, wherein the portion of extracranial tissue is proximate the portion of intracranial tissue;
• applying a pressure at a measurable external pressure value to compel the noninvasive infrared spectroscopy measuring means against the subject cranium while detecting a first signal corresponding to a constant or average blood pressure (DC), and a second signal corresponding to a peak, pulsed blood pressure (AC) in both the extracranial and intracranial portions;
• and
• processing the measured external pressure value and the signals in the extracranial portion and the intracranial portion as the applied pressure is increased, until a state of compliance or equilibrium between the extracranial and intracranial blood vessels is detected, the measured pressure at which state corresponding to the subject cranium's intracranial pressure (ICP) proximate the noninvasive infrared spectroscopy measuring means.