TYPES OF GLAUCOMA
Although glaucoma is commonly referred to as if it were one disease, it would be be more accurate to refer to “the glaucomas” plural. This is because glaucoma is actually a range of conditions in which the common feature is damage to the optic nerve. If you have been diagnosed with glaucoma your eye specialist will tell you which type of glaucoma you have.
Open Angle Glaucoma
In Normal Tension Glaucoma the optic nerve is damaged even though intraocular pressure (IOP) is not particularly high. It is not yet understood why some people suffer optic nerve damage despite having apparently “normal” pressure levels.
The trabecular meshwork is where fluid exits from the eye in the corner, or angle, of a space called the anterior chamber. In Angle Closure Glaucoma (ACG) the angle becomes blocked by part of the iris. Fluid is obstructed from reaching the angle and pressure becomes high. There are various types of Angle Closure Glaucoma such as Intermittent, Chronic, and the sudden and severe Acute Angle Closure Glaucoma.
Pigment Dispersion Syndrome is another condition in which the trabecular meshwork, (the drainage gutter at the front of the eye), is unable to function properly. In Pigment Dispersion Syndrome (PDS) black pigment granules clog the meshwork, which prevents fluid from draining properly.
In Pseudoexfoliation Syndrome (PXF) the trabecular meshwork, (the gutter which drains fluid away), becomes blocked by flaky, white material. It is estimated that PXF accounts for about 25% of glaucoma worldwide.
Children do get glaucoma. In many cases the cause is genetic, but sometimes Paediatric Glaucoma can occur following cataract surgery or following trauma to the eye, or ocular inflammation.