Clinical reference

Optometry Hub

Optometry Hub

About Submit a guide

Iris Conditions

The iris is the visible, pigmented diaphragm that controls pupil size and is a key indicator of anterior segment health. Iris pathology spans congenital structural anomalies, inflammatory disorders, neoplastic lesions, and traumatic injury — many of which carry glaucoma risk requiring prompt recognition and referral.

Last updated: March 2026

Systematic iris evaluation during routine slit-lamp examination is essential. Key triage priorities include new or worsening anterior chamber flare (uveitis), acute angle closure, hyphema, iris transillumination defects, and any pigmented lesion showing documented growth. Co-management with ophthalmology is indicated for glaucoma-associated conditions, neoplastic lesions, and all surgical cases.

Iris disease index (A–Z)

Aniridia

Congenital near-total absence of the iris associated with PAX6 mutations; high risk of foveal hypoplasia, nystagmus, glaucoma, and Wilms tumour in the WAGR syndrome subset.

Anterior Uveitis (Iritis)

Inflammatory cells and flare in the anterior chamber with ciliary flush; most common form of uveitis requiring prompt diagnosis to prevent synechiae, cataract, and glaucoma.

Axenfeld-Rieger Syndrome

Anterior segment dysgenesis with iris strands to a prominent Schwalbe line; ~50% develop glaucoma and systemic anomalies include dental and craniofacial abnormalities.

Corectopia and Polycoria

Displaced or multiple pupils affecting visual axis and light regulation; may be congenital or acquired (trauma, ICE syndrome); important to differentiate true from pseudo-polycoria.

Heterochromia Iridis

Difference in iris colour between eyes (complete) or within one iris (sectoral); may be benign physiological variation or a sign of Horner syndrome, Fuchs uveitis, or acquired disease.

Hyphema

Blood in the anterior chamber from traumatic or spontaneous iris vessel rupture; risk of re-bleed, corneal staining, and glaucoma; sickle cell trait significantly increases complications.

Iridocorneal Endothelial (ICE) Syndrome

Proliferating corneal endothelium migrates across the angle and iris causing progressive glaucoma, corectopia, and iris atrophy; unilateral, predominantly in young-to-middle-aged women.

Iris Atrophy

Progressive thinning or loss of iris stroma and pigment epithelium; essential iris atrophy is a hallmark of ICE syndrome; secondary atrophy follows uveitis, glaucoma, or ischaemia.

Iris Coloboma

Keyhole-shaped iris defect from incomplete closure of the embryonic fissure; may be isolated or part of CHARGE syndrome; assess posterior segment for coexisting chorioretinal coloboma.

Iris Cysts

Fluid-filled epithelial or stromal cysts arising from the iris; most are benign and stationary; large or enlarging cysts may obstruct the visual axis or angle and require intervention.

Iris Melanoma

Anterior uveal melanocytic malignancy; slower growing than posterior uveal melanoma but requires serial monitoring; risk factors include light iris colour and ocular/oculodermal melanocytosis.

Iris Nevus

Benign melanocytic lesion of the iris stroma; found in ~6% of the population; requires serial slit-lamp photography to document stability and exclude malignant transformation.

Pigment Dispersion Syndrome

Reverse pupillary block causes posterior iris bowing against lens zonules, releasing pigment into the trabecular meshwork; leading cause of pigmentary glaucoma in young myopic men.

Plateau Iris Configuration

Anterior ciliary body rotation brings iris periphery into the angle even after iridotomy; risk of appositional closure and angle-closure glaucoma; confirmed by ultrasound biomicroscopy.

Traumatic Iris Damage

Blunt or penetrating trauma may cause iridodialysis, sphincter tears, iris transillumination defects, mydriasis, or iris prolapse; evaluate for concurrent angle, lens, and vitreous injury.

Browse all conditions

Found an error or want to add a condition?

Help us improve this category for clinicians and students.

Submit feedback