Visual acuity degradation in astronauts exposed to microgravity is a newly recognized phenomenon. Prompted by persistent reports of vision changes, NASA began a stepwise operational process to determine the cause
although the exact mechanism is yet to be fully determined, many MRI findings suggest that intracranial hypertension is an important component.
OCT ( Optical Coherence Tomography ) is one technology that is operational @NASA's International Space Station, to study this Visual impairment Intracranial Pressure Syndrome. It is useful to analyse pathologies in the context of raised ICP. It can assess the Retinal Nerve Fibre Layer ( RNFL), total retinal thickness and the optic nerve head volume. But it can't provide a direct indication of raised ICP, is bulky, expensive and need an external energy source.
J Neurosurg Anesthesiol 27/4 Oct/2015
