Overview

Developing a NASA/NSBRI Integrated Garment Solution to Mitigate Visual Impairment Intracranial Pressure Issues During Long Duration Space Flight

Principal Investigator:
Matthew D. Trexler, Ph.D.

Organization:
Under Armour

Technical Summary

The aim of this project will be to construct a fabric based wearable vacuum system to reduce the intracranial pressure of astronauts during space flight which has been linked to the Visual Impairment Intracranial Pressure (VIIP) syndrome observed in astronauts after prolonged duration in space. This impairment poses a great danger to health and safely of astronauts who are spending longer time in microgravity environments.

In a collaborative effort, Under Armour (UA) will design and construct a wearable system for implementation in space. The system will be validated by Dr. Benjamin D. Levine and colleagues at The University of Texas Southwestern Medical Center at Dallas with the aid of NASA astronauts.

Recent work by Levine et al has shown that on Earth bed ridden patients can avoid sustained elevations in ICP simply by elevating the head while sleeping. It is estimated that a relative low vacuum (15 mmHg) environment imposed on the lower body during space flight would be enough to reduce ICP to below high risk levels for VIIP (i.e., equivalent to the upright posture on earth). This is due to the fact that the compliance of the intracranial compartment is so low that minimal reductions in the volume dramatically reduce the pressure.

Earth Applications

Many patients on earth suffer from pathological elevations in intracranial pressure that lead to intractable headaches, and other neurological symptoms. When these elevations are marked, surgical interventions are used to shunt cerebrospinal fluid into other body compartments to reduce intracranial pressure. However when these elevations are only mildly elevated, the risk-benefit ratio of surgical shunting may be unclear. The availability of a comfortable, wearable garment that can reduce intracranial pressure during sleep (when ICP is highest) could provide an alternative to surgical shunting in some patients, and would be a potential therapy that should be compared against other surgical and medical therapies. Other conditions that have been associated with elevated intracranial pressure such as Acute Mountain Sickness, or High Altitude Cerebral Edema, could also, in principle, be treated with low level LBNP at night. The availability of the proposed garment would provide important new avenues for research. Finally, research on regulation of brain blood flow is limited by the inability to induce LBNP inside a MRI magnet. Only a few, very highly technical devices currently exist in specialized centers. The availability of a wearable, non-magnetic garment could open up new avenues for research that have not previously been possible.