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Abstract
The Iris is the anterior part of uveal tract, the intermediate coat of the eyeball.
It is a pigmented circular diaphragm which is present between the lens and the cornea.
It has a central hole: The pupil, the window to the inner eye, through which light passes to reach retinal photoreceptors. It controls amount of light entering the eye and prevents
chromatic aberrations of the light passing through lens periphery.
Being the anterior diaphragm that controls light entrance to the eye, iris defects as cases of aniridia, coloboma of the iris, albinism, tumors of the iris as naevi, melanomas
and leiomyomas and penetrating, blunt or surgical traumas may manifest damage to iris tissue and all need surgical repair.
Surgical management of iris defects may involve alterations to the cornea as corneal tattooing, reconstruction or manipulation of the iris, or insertion of an opaque barrier in the lenticular plane.
Corneal tattoing is practiced by staining or inserting a variety of substances into the corneal tissue by either needle puncture or corneal lamellar dissection.
Iridopexy is addressed to repair iris defects with at least two thirds normal tissue.
It involves repairing sector iridectomy, localized colobomas and sphincteric rupture with pupilloplasty using McCannel suture technique, repairing of iridodialysis using single or double-armed closed system techniques and Iris cerclage suture technique for traumatic mydriasis.
When significant amounts of iris tissue are damaged or missing, iris repair may be impossible and we had no means of restoring the diaphragmatic function of the iris.
In these eyes, artificial iris implants can augment the iris diaphragm.There are different prosthetic iris devices available involving the Morcher single-piece iris-diaphragm IOL styles 67F and 67G, the Morcher endocapsular ring prosthetic iris devices styles 96G
and 50C and The Ophtec model 311 lens and Iris prosthetic system (IPS).
Iris reconstruction is under continuous progress to achieve the best visual outcome.