An iridectomy, also known as a surgical iridectomy or corectomy, is the surgical

Surgery

Surgery is an ancient medical specialty that uses operative manual and instrumental techniques on a patient to investigate and/or treat a pathological condition such as disease or injury, or to help improve bodily function or appearance.An act of performing surgery may be called a surgical...

 removal of part of the iris

Iris (anatomy)

The iris is a thin, circular structure in the eye, responsible for controlling the diameter and size of the pupils and thus the amount of light reaching the retina. "Eye color" is the color of the iris, which can be green, blue, or brown. In some cases it can be hazel , grey, violet, or even pink...

. These procedures are most frequently performed in the treatment of closed-angle glaucoma and iris melanoma

Melanoma

Melanoma is a malignant tumor of melanocytes. Melanocytes are cells that produce the dark pigment, melanin, which is responsible for the color of skin. They predominantly occur in skin, but are also found in other parts of the body, including the bowel and the eye...

.

Comparison with Nd:YAG laser iridotomy

In acute angle-closure glaucoma cases, surgical iridectomy has been superseded by Nd:YAG laser

Nd:YAG laser

Nd:YAG is a crystal that is used as a lasing medium for solid-state lasers. The dopant, triply ionized neodymium, typically replaces yttrium in the crystal structure of the yttrium aluminium garnet , since they are of similar size...

 iridotomy, because the laser procedure is much safer. Opening the globe for a surgical iridectomy in a patient with high intraocular pressure

Intraocular pressure

Intraocular pressure is the fluid pressure inside the eye. Tonometry is the method eye care professionals use to determine this. IOP is an important aspect in the evaluation of patients at risk from glaucoma...

 greatly increases the risk of suprachoroidal hemorrhage, with potential for associated expulsive hemorrhage. Nd:YAG laser iridotomy avoids such a catastrophe by laser created hole in the iris, which facilitates flow of aqueous humor from the posterior to the anterior chamber

Anterior chamber

The anterior chamber is the fluid-filled space inside the eye between the iris and the cornea's innermost surface, the endothelium. Aqueous humor is the fluid that fills the anterior chamber. Hyphema and glaucoma are two main pathologies in this area. In hyphema, blood fills the anterior chamber...

 of the eye.

Current indications

Surgical iridectomy is commonly indicated and performed in the following cases:

• Cataract surgery in a glaucoma patient
• Combined procedure for cataract and glaucoma
• Acute closed-angle glaucoma
• Posterior capsular tears with vitreous loss
• Implantation of anterior chamber IOL
  Intraocular lens
  An intraocular lens is an implanted lens in the eye, usually replacing the existing crystalline lens because it has been clouded over by a cataract, or as a form of refractive surgery to change the eye's optical power. It usually consists of a small plastic lens with plastic side struts, called...
  
  .
• Vitreoretinal procedure involving injection of silicon oil. The location of the iridectomy in such cases is at 6'O Clock, as opposed to routine iridectomy done at 11 to 1'O Clock. This is because silicon oil is lighter than water.
• Iris trauma

Types

• An antiphogistic iridectomy is the surgical removal of part of the iris to reduce intraocular pressure in inflammatory conditions of the eye.
• A basal iridectomy is an iridectomy which includes the root of the iris.
• An optical iridectomy is the surgical removal of part of the iris to enlarge the existing pupil, or to form an artificial pupil, when the natural pupil is ineffectual.
• A peripheral iridectomy is the surgical removal of a portion of the iris in the region of its root, leaving the pupillary margin and sphincter pupillae muscle intact. It is used in the treatment of glaucoma.
• A preliminary iridectomy, or preparatory iridectomy, is the surgical removal of part of the iris preceding cataract extraction. It facilitates the removal of the cataract
  Cataract
  A cataract is a clouding that develops in the crystalline lens of the eye or in its envelope, varying in degree from slight to complete opacity and obstructing the passage of light...
  
  ous lens
  Lens (anatomy)
  The crystalline lens is a transparent, biconvex structure in the eye that, along with the cornea, helps to refract light to be focused on the retina. The lens, by changing shape, functions to change the focal distance of the eye so that it can focus on objects at various distances, thus allowing a...
  
  .
• A sector iridectomy, also known as a complete iridectomy or total iridectomy, is the surgical removal of a complete radial section of the iris extending from the pupillary margin to the root of the iris. A key-hole pupil is left by the removal of a wedge-shaped section of iris.
• A stenopeic iridectomy is the surgical removal of a narrow slit or a minute portion of the iris, leaving the sphincter pupillae muscle intact.
• A therapeutic iridectomy is the surgical removal of a portion of the iris for the cure or prevention of an ocular disease.