Glaucoma

]

Treatment

Although intraocular pressure is only one of the causes of glaucoma, at the current time lowering it is the mainstay of glaucoma treatment.

~ ~ ~ ~ ~ ~ ~ ~ ~ ~

Drugs

Intraocular pressure can be lowered with medication,usually eye drops. There are several different classes of medications to treat glaucoma with several different medications in each class. Topical beta-adrenergic receptor antagonists such as timolol and betaxolol decrease aqueous humor production by the ciliary body. Alpha2-adrenergic agonists such as brimonidine (Alphagan) work by decreasing aqueous production. Less-selective sympathomimetics like epinephrine and dipivefin (Propine) increase outflow of aqueous humor through trabecular meshwork and possibly through uveoscleral outflow pathway, probably by a beta2-agonist action. Miotic agents (parasympathomimetics) like pilocarpine work by contraction of the ciliary muscle, tightening the trabecular meshwork and allowing increased outflow of aqueous through traditional pathways. Carbonic anhydrase inhibitors like dorzolamide (Trusopt), brinzolamide (Azopt), acetazolamide (Diamox) lower secretion of aqueous humor by inhibiting carbonic anhydrase in the ciliary body. Prostaglandin analogs like latanoprost (Xalatan), bimatoprost (Lumigan) and travoprost (Travatan) increase uveoscleral outflow of aqueous.

Related Topics:
Timolol - Betaxolol - Brimonidine - Sympathomimetic - Epinephrine - Dipivefin - Parasympathomimetic - Pilocarpine - Dorzolamide - Brinzolamide - Acetazolamide - Prostaglandin - Latanoprost - Bimatoprost - Travoprost

~ ~ ~ ~ ~ ~ ~ ~ ~ ~

Marijuana has been shown to lower the intraocular pressure in some eyes in a few studies but this is generally not used clinically.

~ ~ ~ ~ ~ ~ ~ ~ ~ ~

The possible neuroprotective effects of various topical and systemic medications are also being investigated.

~ ~ ~ ~ ~ ~ ~ ~ ~ ~

Surgery

(See Eye surgery.)

~ ~ ~ ~ ~ ~ ~ ~ ~ ~

Both laser and conventional surgeries are performed to treat glaucoma. Laser trabeculoplasty may be used to treat open angle glaucoma. An argon or Nd:YAG laser spot is aimed at the trabecular meshwork to stimulate opening of the mesh to allow more outflow of aqueous fluid. Laser peripheral iridectomy may be used in patients susceptible to angle closure glaucoma. In it, the laser is aimed at the iris to make an opening in it. This allows a new channel for fluid to flow when the usual channel through the dilated pupil is blocked.

~ ~ ~ ~ ~ ~ ~ ~ ~ ~

The most common conventional surgery performed for glaucoma is the trabeculectomy. Here, a partial thickness flap is made in the scleral wall of the eye, and a window opening made under the flap to remove a portion of the trabecular meshwork. The scleral flap is then sutured loosely back in place. This allows fluid to flow out of the eye through this opening, resulting in lowered intraocular pressure.

~ ~ ~ ~ ~ ~ ~ ~ ~ ~

There are also several different small tubes that are inserted into the anterior chamber of the eye and out underneath the conjunctiva to allow flow of fluid out of the eye.

~ ~ ~ ~ ~ ~ ~ ~ ~ ~