Essays
https://doi.org/10.3325/cmj.2021.62.420
A contribution to the understanding of ocular and cerebrospinal fluid dynamics in astronauts during long-lasting spaceflight
Darko Orešković
; Department of Molecular Biology, Ruđer Bošković Institute, Zagreb, Croatia
Milan Radoš
; Department of Pharmacology and Croatian Institute for Brain Research, Zagreb University School of Medicine, Zagreb, Croatia
Marijan Klarica
; Department of Pharmacology and Croatian Institute for Brain Research, Zagreb University School of Medicine, Zagreb, Croatia
Abstract
Zhang and Hargens (1) reviewed the knowledge on visual
impairment intracranial pressure (VIIP) syndrome in astronauts, a condition that arises as a consequence of long-lasting spaceflight. However, the etiology and pathophysiology of VIIP syndrome remain unclear and only hypothetical.
The main reason is the absence of data regarding astronauts’ intracranial (ICP) and intraocular pressure (IOP) during long-lasting spaceflights. It is believed that a crucial
role in the pathogenesis of VIIP syndrome is played by
chronic ICP/IOP mismatch, which is a consequence of
chronically elevated ICP and which results in translaminar pressure gradient. A direct transmission of elevated
ICP from the intracranial to the intraocular compartment
through the perioptic subarachnoid space should lead
to optic nerve sheath distension and disk edema. Therefore, elevated pressure gradient across the lamina cribrosa
caused by chronic, gently elevated ICP should finally cause
posterior-globe flattening, disk edema, choroid folds, and
a hyperoptic shift (1)
Keywords
Hrčak ID:
278455
URI
Publication date:
26.8.2021.
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