Glaucoma Surgery
Glaucoma surgeries consist of a number of variations and even combinations of a number of surgical procedures which help to treat Glaucoma, which is a group of diseases which affect the optic nerve of the eye. There are two types of glaucoma surgeries, namely those which facilitate the escape of excess aqueous humor from the eye and those which decrease the production of aqueous humor. Both, however, are used to reduce intraocular pressure.
Types of Glaucoma Surgery
There are numerous types of glaucoma surgery options available to an ophthalmologist, with the more popular techniques being used detailed below:
Procedures Which Facilitate the Outflow of Aqueous Humor
Laser Trabeculoplasty:
Also known as LTP, it is the use of a surgical laser to burn areas of the trabecular meshwork, which is located near the base of the iris, to increase fluid outflow. This method of glaucoma surgery is generally used to treat open-angle glaucomas. There are two variations of laser trabeculoplasty, which are argon laser trabeculoplasty ( also known as ALT) and selective laser trabeculoplasty (also known as SLT). Selective laser trabeculoplasty is the newer technology of the two options and creates less thermal damage than ALT.
Iridotomy:
This eye surgery procedure can be performed with either standard surgical instruments or a surgical laser. These instruments are used to make an opening through the iris without the removal of iris tissue to assist with the lowering of intraocular pressure. This type of eye surgery is usually used to treat patients with angle-closure glaucoma. When a laser peripheral iridotomy, or LPI,is performed either an argon laser or Nd:YAG laser is used to perform the procedure.
Iridectomy:
An iridectomy is the removal of a portion of iris tissue to release intraocular pressure. There are three types of corectomy or surgical iridectomy, namely a sector iridectomy, a basal iridectomy and a peripheral iridectomy. A peripheral iridectomy is the removal of iris tissue at the periphery, a basal iridectomy is the removal of iris tissue from the far periphery and a sector iridectomy is the removal of a wedge-shaped section of the iris.
Viscocanalostomy:
A Viscocanalostomy is a major eye surgery procedure in which Schlemm's canal is exposed. This procedure creates a large and very deep scleral flap which allows for the cannulation of the Schlemm's canal and the injection of a viscoelastic substance which dilates the Schlemm's canal and the aqueous collector channels.
Procedures Which Decrease the Production of Aqueous Humor
Procedures which decrease the production of aqueous humor is a ciliary destructive or cyclodestructive procedure which is used to destroy cells within the eye's ciliary body which produce aqueous humor. The most prevalent treatments are as follows:
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Cyclocryotherapy:
This eye surgery procedure uses a freezing probe to initiate transscleral cyclophotocoagulation which causes ciliary body ablation.
Cyclodiathermy:
Cyclodiathermy uses heat generated from a high frequency alternating electric current to achieve ciliary body ablation.
Cyclophotoablation and Cyclophototherapy:
These eye surgery processes both use a laser to attain ciliary body ablation.
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References
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