BECAUSE ALL PARTS OF HUMAN PHYSIOLOGY ARE AFFECTED BY MICROGRAVITY AN INTEGRATIVE COUNTERMEASURE STRATEGY IS NEEDED. LOSS OF MUSCLE AND BONE MASS ALONG WITH DECONDITIONING OF THE HEART AND VESSELS ARE WELL DESCRIBED EFFECTS OF MICROGRAVITY. MORE RECENTLY STRUCTURAL AND FUNCTIONAL CHANGES OF THE EYE EXPERIENCED BY SOME ASTRONAUTS DURING LONG-TERM MISSIONS HAVE BEEN DESCRIBED AND SUMMARIZED IN THE SPACEFLIGHT-ASSOCIATED NEURO-OCULAR SYNDROME (SANS). WHILE THE EXACT ETIOLOGY OF SANS REMAINS UNKNOWN THE MICROGRAVITY INDUCED HEAD-WARD FLUID SHIFT IS LIKELY PART OF THE PATHOPHYSIOLOGY AND COUNTERMEASURES THAT CAN REVERSE THIS FLUID SHIFT ARE PRIORITIZED. BASED ON OUR EXPERIMENTAL DATA FROM SHORT-TERM MICROGRAVITY BY PARABOLIC FLIGHTS AND 24-HOUR SIMULATED MICROGRAVITY WE SUGGEST THAT FLUID REDISTRIBUTION IN SPACE MAY NOT GIVE RISE TO A PATHOLOGICAL INCREASE IN INTRACRANIAL PRESSURE BUT RATHER THE LACK OF DIURNAL FLUCTUATIONS IN INTRACRANIAL VOLUME AND PRESSURES MAY BE RESPONSIBLE FOR THE REMODELING OF THE EYE. IN AMBULATORY NEUROSURGICAL PATIENTS WITH PRESSURE SENSORS INSERTED IN THE BRAIN TISSUE WE THEREFORE DEMONSTRATED THE FEASIBILITY OF LOWER BODY NEGATIVE PRESSURE TO REDUCE INTRACRANIAL PRESSURE AS MEANS OF RE-INTRODUCING DIURNAL PRESSURE VARIABILITY.