Direct Intracranial Pressure Monitoring Grant

The Direct Intracranial Pressure Monitoring Grant by the Translational Research Institute for Space Health seeks innovative proposals for real-time measurement of intracranial pressure (ICP) in astronauts during commercial spaceflight. This initiative aims to address the Spaceflight Associated Neuro-ocular Syndrome (SANS) by exploring both direct and non-invasive ICP measurement methods. Selected projects will contribute to the EXPAND program, enhancing our understanding of ICP's role in astronaut health and safety during long-duration missions.

TRISH is seeking proposals to solutions for real-time direct measurement of intracranial pressure (ICP) in crew during commercial spaceflight. Selected project(s) will be part of the Institute's Enhancing eXploration Platform and ANalog Definition (EXPAND) Program.
Proposals must also include ways to estimate intracranial pressure using methods that are not invasive to the crew. These estimations will be used as a benchmark against historical methods with the goal of understanding their validity.
Methods for direct ICP measurement can help TRISH determine what role, if any, changes in ICP during spaceflight plays in Spaceflight Associated Neuro-ocular Syndrome (SANS), a major concern for human spaceflight.
B. Opportunity

1. Background

The Spaceflight Associated Neuro-ocular Syndrome (SANS) is a major concern for human spaceflight. SANS is a disorder that affects astronauts after long-duration space travel, causing swelling of the optic nerve, chorioretinal folds, flattening of the optic globe, and changes in near vision (Mader et al., 2011). As many as 70% of astronauts develop SANS, which poses a significant risk for space missions and specifically for long-duration space missions (i.e., mission to Mars) because it can lead to severe vision changes that could jeopardize the ability to function safely or control a spacecraft (Patel et al., 2020).
Previous studies have suggested that abnormal intracranial pressure (ICP) may be the underlying cause of SANS. This is primarily because there has been no systematic evaluation of ICP in astronauts, and non-invasive methods for estimating ICP have been insufficient. Non-invasive methods like measuring optic nerve sheath diameter, transcranial Doppler, otoacoustic emissions, tympanic membrane displacement, and others may give some insight into ICP, but these methods lack precision and accuracy. Moreover, none of the non-invasive methods allow for continuous ICP measurement during wakefulness or sleep, or assessment of the ICP waveform and pulse pressure, which provide important information about craniospinal compliance. Lumbar punctures, a standard method for measuring ICP, are considered too risky for International Space Station (ISS) missions because of the potential risk to government astronauts being unable to perform other missioncritical responsibilities, should complications arise (Barr, 2014).
It is still unknown if the spaceflight environment itself increases ICP or if changes associated with the SANS disorder have another cause. Elucidating this unknown will inform potential countermeasures to the SANS disorder.

1. Goal of the Appendix

This Appendix solicits for research to be conducted on an orbital commercial spaceflight mission. Proposals must focus on direct solutions for real-time ICP measurement in astronauts during spaceflight (see section B.2.a). Additionally, proposals must include non-invasive ICP estimation measurements to benchmark against existing methods and validate their effectiveness, with the goal of understanding the validity of existing methods of non-invasive estimations of ICP (see section B.2.b). Proposals must address both aspects of the single topic.
Funded studies will become a part of the TRISH Enhancing eXploration Platforms and ANalog Definition (EXPAND) program. Any studies awarded through this Appendix that yield data or samples will also be stored in the EXPAND Database and made available for future data requests. For more information about the EXPAND program and the EXPAND Database please visit the TRISH Broad Institute Announcement and the TRISH EXPAND website.