“Dual-pressure theory” in pathogenesis of glaucomatous optic neuropathy from the Beijing intracranial and intraocular pressure study

Abstract

The mechanical theory of glaucoma indicates that high intraocular pressure (IOP) leads to glaucomatous optic nerve damage. However, nearly half of primary open-angle glaucoma patients with normal intraocular pressure also exhibit progression of what appears to be glaucomatous optic nerve damage. Our earlier prospective study identified for the first time that the relatively low intracranial pressure (ICP) is also an important risk factor for progressive glaucomatous injury of normal-tension glaucoma. When considering the results of studies in nonhuman primates, clinical research, large-scale natural-population studies, and basic laboratory investigations, a new understanding of the pathophysiology of glaucoma, the “Dual-Pressure Theory”, has been proposed. This theory states that “either high IOP or low ICP contributes to increasing the translaminar cribrosa pressure difference; it is the pressure difference rather than the IOP alone that results in the glaucomatous optic neuropathy”. Here, we provide a systematic introduction to Dual-Pressure Theory relating to glaucoma, the form of a research map, an outline of basic laboratory investigations, the main methodology, and research updates.