Clinical Pearls

• Glaucoma is a group of diseases and is defined as any pressure inside the eye that damages the optic nerve 

• It is called the "silent thief of sight" because the damage usually occurs very gradually over many years. Often, a patient will come in for a glasses exam and discover they have Glaucoma, and also have considerable loss of peripheral vision without even knowing! 

• Conceptually, think of Glaucoma as a sink. Either the water is flowing out too fast, or the drain is clogged (or both).  In an open system, the sink will just overflow. However, in a closed system such as the eye, the fluid has nowhere to go, so the pressure inside rises. 

• High IOP is caused by improper balance of production and drainage of aqueous humor (flow vs. drainage). Glaucoma therapies are targeted at either decreasing the fluid production, and/or trying to unclog the drain

• Normal IOP Range:  10- 21 mmHg

• We measure the progress by measuring the IOP, measuring the cup to disc (C/D) ratio of the optic nerve, as well as monitoring their visual fields

• The loss of vision starts with the peripheral vision and is irreversible. As Glaucoma progresses, the field of vision will become more narrow

• There are around 40 different types of Glaucoma!!

• Risk factors include: positive family history, age (over 40), race (African American, Hispanic, & Asian are most common)

Most Common Types of Glaucoma

Primary Open Angle Glaucoma (POAG)

• Patient has open angles, but with high IOP and optic nerve damage

Narrow Angle Glaucoma (NAG)

• Patient has anatomical narrow angles (ANA) and can lead to an angle closure attack

• Think Hyperopia!

Ocular Hypertension (OHTN)

• Patient has high IOP but without any damage to the optic nerve or loss of visual field (yet.....)

Low- Tension Glaucoma (LTG)

• Patients IOP is low to normal, but still has damage to optic nerve and vision loss

Glaucoma Suspect

• Patient doesn't have glaucoma yet, but has one or more risk factors to develop it

Pigmentary Glaucoma

• When pigment from the iris flakes off and clogs the eyes drainage system

Pseudoexfoliation Glaucoma (PXG)

• Protein deposition in the eye clogs the drainage syndrome

• Seen in 50% of patient with Pseudoexfoliation syndrome (systemic)

Secondary Glaucoma

• Caused by eye trauma, inflammation, diabetes, steroid use, tumors, cataracts, and Sickle Cell Anemia

Clinical Pearls

There are many different types of glaucoma drops, but the shared idea behind them is to decrease pressure inside the eye by one of two ways:

1. Decrease production of Aqueous Humor, thereby decreasing the pressure

2.  Increasing the drainage of Aqueous Humor by the Trabecular Meshwork, thereby decreasing the pressure

• Combination of Brinzolamide & Brimonidine

• Taken BID or TID