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Several biomechanical factors have been associated with the development of glaucoma. However, although optic nerve head (ONH) biomechanics have been previously analysed, other ocular zones have been less explored. Therefore, in this study, the effect of intraocular and cerebrospinal fluid pressure (CSFP) on the ONH, peripapillary region (PPR), optic nerve subarachnoid space (SAS) and meninges have been investigated. Two finite element models of the eye were made from one anatomical configuration, including the complete PPR (choroid, retina, and sclera), all meningeal layers and the SAS. Each of the models were subjected to 12 different eye pressures, and one model was additionally subjected to 20 cerebrospinal pressures. Furthermore, the biomechanical impact of each meningeal layer and SAS on the ONH and PPR was assessed. Global results indicated that the greatest strains occurred in the retina, followed by the prelaminar region and lamina cribrosa (LC). With an increase in intraocular pressure (IOP), all of the PPR showed thinning; nevertheless, the retina was the layer most affected. Additionally, the results showed that the postlaminar tissue was the region most deformed by CSFP variations. Despite this, a low CSFP, associated with ocular hypertension, caused an increase in retinal, choroidal and LC strains, and posterior displacement of central and medial regions of the LC and prelaminar tissue, as well as a change in postlaminar tissue biomechanics. Finally, the meninges produced an important reduction in ONH strains due to IOP fluctuations, and variations in SAS stiffness had a strong influence on strains within the ONH and PPR. Keywords: Glaucoma, Physiopathology, Choroid, Retina, Sclera, Meninges, Subarachnoid space