An innovative absolute intracranial pressure (aICP) measurement technology has been proposed (US, EU and Japan patents) which does not need a calibration of the system "individual patient-noninvasive ICP meter".A new method is based on two-depth TCD technique for aICP and external absolute pressure aPe comparison using the ophthalmic artery (OA) as natural pressure measurement "scales".The intracranial segment of OA is compressed by aICP and the extraeranial segment is compressed by aPe applied to the tissues surrounding the eye.The blood flow parameters in both OA segments are approximately the same when aPe =aICP.Special multichannel / multidepth TCD device is used as an indicator of balance aPe =aICP.