I have no idea what you mean. What do you mean by an eye sphere? Are you asking about glaucoma, where pressure in the eye is increased above normal? That's not due to pressure in veins (or arterioles for that matter either).
I suspect "eye sphere" = eyeball. Literal translation in some non-English languages.
"The intraocular pressure (IOP), an important part of any eye exam, is measured with a special instrument called a tonometer. The IOP is determined by a balance of the eye’s production and drainage of aqueous (the clear fluid inside the eye) from the anterior chamber into the trabecular meshwork. If the IOP is elevated, it can cause pressure within the eye to increase and damage the optic nerve." from http://www.stlukeseye.com/eyeq/IOP.asp [Broken]
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