The aqueous humour is a transparent water-like fluid similar to blood plasma, but containing low protein concentrations.

Small variations in the production or outflow of aqueous humor will have a large influence on the intraocular pressure.

[7] The secondary route is the uveoscleral drainage, and is independent of the intraocular pressure, the aqueous flows through here, but to a lesser extent than through the trabecular meshwork (approx.

[7] Glaucoma is a progressive optic neuropathy where retinal ganglion cells and their axons die causing a corresponding visual field defect.

However, increased interocular pressure is neither sufficient nor necessary for development of primary open angle glaucoma, although it is a major risk factor.