Abstract
The initial terminology for the observed changes in visual acuity in astronauts during long-duration spaceflight (LDSF) was visual impairment owing to intracranial pressure (VIIP), because all five symptomatic LDSF astronauts with postflight lumbar punctures had shown an elevated opening pressure even weeks after a landing.The National Aeronautics and Space Administration (NASA) then went on to rename VIIP as spaceflight-associated neuro-ocular syndrome (SANS) and, at the same time, refrained from using the word papilloedema in the publications, opting for the more neutral description optic disc oedema instead.In hindsight, from the perspective of European researchers, it remains unclear to us whether this was entirely motivated on clinical and scientific grounds or a mere marketing strategy to avoid scaring away political funding.A slowly developing hydrocephalus in microgravity certainly does not sound desirable to aspiring space cadets.But the rebranding from VIIP to SANS did more to obscure than directly to address this major human health risk, which is currently classified as 'red risk' by the agency.And in the long term, the aim of all involved researchers and physicians is to derisk human spaceflight and exploration FIGURE 1.