Iris and Ciliary Body Disorders

Lecture Outline

  • Objectives: Understanding congenital and developmental anomalies of the iris.

  • Congenital and Developmental Iris Anomalies: Major focus of the lecture.

  • Summary: Key points will be recapped.

Lecture Objectives

  • Discuss congenital and developmental anomalies of the iris.

Abnormalities of the Iris

  • ICD-10 Codes:

  • H21.XYZ: Other disorders of the Iris and Ciliary Body.

  • Q13.X: Congenital malformation of the anterior segment of the eye.

Coloboma

  • Definition: "Keyhole" pupils resulting from failure of optic fissure closure during development.

  • Associations: Can be linked to syndromes; if iris only, affects light sensitivity.

Related Systemic Disease: CHARGE Syndrome

  • Components:

  • Coloboma

  • Heart defects

  • Atresia of the chonae

  • Growth/development delay

  • Genital/urinary abnormalities

  • Ear anomalies

Colobomas Effects

  • Retinal/macular lesions can lead to Visual Acuity (VA) loss and field defects.

Hypoplasia of the Iris

  • Definition: Partial absence of the iris.

Aniridia (Q13.1)

  • Definition: Complete absence of the iris; root seen on gonioscopy.

  • Associated Conditions:

  • Glaucoma

  • Cataract

  • Wilms Tumour (kidney tumour in young children)

Gonioscopy in Aniridia

  • Gonioscopy shows a remnant of the iris root; normal chamber angle occluded.

Persistent Pupillary Membranes (PPM)

  • Occurs if atrophy of pupillary membrane is incomplete by 6 months gestation.

  • Common in 95% of normal newborns; can connect to iris/lens and cause amblyopia.

Persistent Pupillary Membrane Presentation

  • A. Right eye: fenestrated, thick brown membranes.

  • B. Left eye: dense strands of pupillary membranes.

Iris Colour Abnormalities

  • Heterochromia Iridis: Variation in iris color between eyes.

  • Sectoral Heterochromia: Variation within a single iris.

Conditions Affecting Iris Colour

  • Congenital:

  • Waardenburg's syndrome

  • Horner's syndrome

  • Aniridia

  • Coloboma

  • Sturge-Weber syndrome

  • Acquired:

  • Fuchs' heterochromic iridocyclitis

  • Glaucoma treatments (e.g., latanoprost)

  • Trauma or surgery

  • Iris melanoma

Iris Syndromes

  • Fuch’s Heterochromatic Iridocyclitis: Affects iris and causes inflammation.

  • Axenfeld Rieger Syndrome: Associated with multiple systemic issues, glaucoma risk.

  • ICE Syndrome: Involves cornea, angle, and iris abnormalities.

Axenfeld-Rieger Syndrome (Q13.81)

  • Prevalence: Autosomal dominant, ~1 in 200,000.

  • Clinical Features:

  • Posterior embryotoxon and various iris abnormalities (hypoplasia, correctopia, polycoria).

  • Systemic abnormalities: dental issues, broad facial features, umbilical skin excess.

  • High risk of glaucoma development.

ICE Syndrome Overview

  • Effects: Aberrations in cornea, angle, iris. May involve unknown infections or be congenital.

  • Symptoms: Corneal edema, glaucoma, iris issues such as corectopia and atrophy.

  • Variants: Chandler’s Syndrome, Progressive Essential Iris Atrophy, Cogan-Reese Syndrome.

Epidemiology of ICE Syndrome

  • Typically unilateral, more common in females; often presents between ages 20-50.

Chandler's Syndrome

  • Description: ~50% of ICE cases; confined corneal involvement, characterized by corneal edema.

Essential/Progressive Iris Atrophy

  • Definition: Ranges from subtle to full thickness atrophy, often leading to synechiae and severe complications.

Cogan-Reese Syndrome

  • Characteristics: Pigmented iris lesions, less serious atrophy but glaucoma may develop.

Differential Diagnosis of ICE Syndrome

  • Key Conditions:

  • Posterior Polymorphous Dystrophy

  • Axenfeld-Reiger Syndrome

  • Fuch’s Endothelial Dystrophy

Summary

  • Majority of congenital iris abnormalities are rare but often tied to glaucoma. Persistent pupillary membranes are common.

  • Acquired iris abnormalities are often features of systemic diseases.