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

surgical Surgery is a medical specialty that uses manual and instrumental techniques to diagnose or treat pathological conditions (e.g., trauma, disease, injury, malignancy), to alter bodily functions (e.g., malabsorption created by bariatric surgery ...

removal of part of the iris.Cline D; Hofstetter HW; Griffin JR. ''Dictionary of Visual Science''. 4th ed. Butterworth-Heinemann, Boston 1997. Surgery Encyclopedia - "Iridectomy."
Encyclopedia of Surgery: A Guide for Patients and Caregivers. Retrieved May 20, 2006. These procedures are most frequently performed in the treatment of closed-angle glaucoma and iris

melanoma Melanoma is the most dangerous type of skin cancer; it develops from the melanin-producing cells known as melanocytes. It typically occurs in the skin, but may rarely occur in the mouth, intestines, or eye (uveal melanoma). In very rare case ...

Comparison with Nd:YAG laser iridotomy

In acute angle-closure glaucoma cases, surgical iridectomy has been superseded by Nd:YAG laser iridotomy, because the laser procedure is much safer. Opening the globe for a surgical iridectomy in a patient with high

intraocular pressure Intraocular pressure (IOP) 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 of glaucoma. Most tonometers are calibrated t ...

greatly increases the risk of

suprachoroidal hemorrhage Intraocular hemorrhage (sometimes called hemophthalmos or hemophthalmia) is bleeding inside the eye (''oculus'' in Latin). Bleeding can occur from any structure of the eye where there is vasculature or blood flow, including the anterior chamber, vi ...

, with potential for associated expulsive hemorrhage. Nd:YAG laser iridotomy avoids such a catastrophe by using a laser to create a hole in the iris, which facilitates flow of

aqueous humor The aqueous humour is a transparent water-like fluid similar to blood plasma, but containing low protein concentrations. It is secreted from the ciliary body, a structure supporting the lens of the eyeball. It fills both the anterior and the po ...

from the posterior to the

anterior chamber The anterior chamber ( AC) is the aqueous humor-filled space inside the eye between the iris and the cornea's innermost surface, the endothelium. Hyphema, anterior uveitis and glaucoma are three main pathologies in this area. In hyphema, ...

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. * Vitreoretinal procedure involving injection of

silicone oil A silicone oil is any liquid polymerized siloxane with organic side chains. The most important member is polydimethylsiloxane. These polymers are of commercial interest because of their relatively high thermal stability and their lubricating prop ...

. 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 silicone oil is less dense 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 A cataract is a cloudy area in the lens (anatomy), lens of the eye that leads to a visual impairment, decrease in vision of the eye. Cataracts often develop slowly and can affect one or both eyes. Symptoms may include faded colours, blurry or ...

ous

lens A lens is a transmissive optical device that focuses or disperses a light beam by means of refraction. A simple lens consists of a single piece of transparent material, while a compound lens consists of several simple lenses (''elements'') ...

. * 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.Cassin, B. and Solomon, S. ''Dictionary of Eye Terminology''. Gainesville, Florida: Triad Publishing Company, 1990. * 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.

References

{{Eye surgery Eye surgery

Comparison with Nd:YAG laser iridotomy

Current indications

Types

See also

References