A mathematical model of whole body and cerebral hemodynamics is a useful tool for investigating visual impairment and intracranial pressure (VIIP), a recently described condition associated with space flight. VIIP involves loss of visual acuity, anatomical changes to the eye, and, usually, elevated cerebrospinal fluid pressure. Loss of visual acuity is a significant threat to astronaut health and performance. It is therefore important to understand the pathogenesis of VIIP. Some of the experimental measurements that could lead to better understanding of the pathophysiology are impossible or infeasible on orbit. A computational implementation of a mathematical model of hypothetical pathophysiological processes is therefore valuable. Such a model is developed, and is used to investigate how changes in vascular compliance or pressure can influence intraocular or intracranial pressure.