Glaucoma pathophysiology
|
Glaucoma Microchapters |
|
Diagnosis |
|---|
|
Treatment |
|
Case Studies |
|
Glaucoma pathophysiology On the Web |
|
American Roentgen Ray Society Images of Glaucoma pathophysiology |
|
Risk calculators and risk factors for Glaucoma pathophysiology |
Please help WikiDoc by adding more content here. It's easy! Click here to learn about editing.
Editor-In-Chief: C. Michael Gibson, M.S., M.D. [1] Associate Editor(s)-in-Chief: Rohan Bir Singh, M.B.B.S.[2]
Pathophysiology
The underlying pathogenesis of glaucoma is attributed to retinal ganglion cell death due to elevated level of intraocular pressure. The intraocular pressure is determined by the balance between secretion of aqueous humor by the ciliary body and its drainage through the two pathways i.e. the trabecular meshwork and uveoscleral outflow pathway.
Primary Open Angle Glaucoma
An elevated IOP can lead to damage the optic nerve head via induced mechanical changes at the lamina cribrosa, or via vascular dysfunction and resultant ischemia. Multiple underlying mechanisms can result in elevated IOP, usually as a consequence of reduced aqueous outflow. These structural changes include:
- Outflow reduction due to obstruction of the trabecular meshwork by a foreign material such as glycosaminoglycans, red blood cells.
- Trabecular beams fusing due to endothelial cell loss.
- Phagocytic activity leading to endothelial cell loss.
- Loss of giant vacuoles from Schlemm’s canal endothelium.
- Reduction of Schlemm’s canal pore size.
Angle Closure Glaucoma
The angle-closure glaucoma occurs due to the obstruction in access to the drainage pathways .
A number of studies also suggest that there is a correlation, not necessarily causal, between glaucoma and systemic hypertension (i.e. high blood pressure). In normal tension glaucoma, nocturnal hypotension may play a significant role. On the other hand there is no clear evidence that vitamin deficiencies cause glaucoma in humans, nor that oral vitamin supplementation is useful in glaucoma treatment[1].
References
- ↑ Rhee DJ, Katz LJ, Spaeth GL, Myers JS (2001). "Complementary and alternative medicine for glaucoma". Surv Ophthalmol. 46 (1): 43–55. PMID 11525790.