This PowerPoint presentation describes the clinical anatomy of the iris and ciliary body. The basics of pupillary examination are also covered.

1. Anatomy, Physiology and Clinical
Aspects of Iris and Ciliary Body
Dr. Brajesh Lahri
Senior Resident
Dr. RP Centre for Ophthalmic Sciences
AIIMS Delhi

2. Introduction
• Uvea is the middle layer of the
eyeball and is classically divided
into 3 parts :
• A) Iris
• B) Ciliary Body
• C) Choroid

3. Iris
• It is a thin, contractile, circular structure,
similar to the diaphragm of a camera.
• Anterior extension of the uveal tract
• Extends from the iris root to the iris
margin.
• The central opening in the iris is known as
the pupil.
• The main function is to regulate the
amount of light entering the eye, which
occurs by increasing or decreasing the
diameter of the pupil.
• Changes in the diameter of pupil occur by
muscles present in the iris.

4. Anatomy of Iris
• Gross Anatomy:
• It has a rough anterior and
smooth posterior surface
• Anterior part is divided into the
Inner pupillary zone and outer
ciliary zone.
• Microscopic Anatomy:
• The layers of the iris are (anterior to posterior)
• Anterior limiting layer
• Iris Stroma
• Sphincter pupillae muscle
• Dilator pupillae muscle
• Anterior pigment epithelium
• Posterior pigment epithelium

5. Blood Supply of Iris
• Supplied by the major and minor
arterial circle
• Anterior Ciliary artery and Long
Posterior ciliary artery form the
major part of the arterial circle.
• The blood vessels run radially in
the iris.

6. Nerve Supply of Iris
• Sympathetic Supply: Starts from C8-
T1 level of spinal cords, supplies
dilator pupillae muscle of the iris.
• Parasympathetic Supply: Starts from
Oculomotor-Edinger-Westphal
Nucleus Complex in the midbrain,
supplies sphincter pupillae muscle of
the iris.
• Dilation of the Pupil  Sympathetic
System
• Constriction of the Pupil 
Parasympathetic System

7. Pupillary Reflex

8. RAPD

9. Clinical Pearls
• Causes of RAPD
1. Optic Neuritis
2. Non-arteritic ischemic optic
neuropathy (NAION)
3. Advanced stage of Glaucoma
4. CRAO,CRVO, BRAO,BRVO
5. Long-standing Retinal
Detachment
• Causes of Fixed Dilated Non-
reacting pupil
1. Medications: Tropicamide,
Atropine, Homatropine,
Cocaine, Phenylephrine
2. Trauma
3. Pupil involving 3rd Nerve Palsy
4. Deep anesthesia

10. Ciliary Body
• Ciliary Body is the anterior-most
continuation of choroid beyond
Ora Serrata.
• Divided into two parts: The
anterior part has finger-like
projections called pars plicata
and the posterior smooth part is
called pars plana.
• The main role is production of
aqueous and accommodation.

11. Anatomy of Ciliary Body
• Blood Supply and Nerve Supply
• Ciliary Plexus provides the majority of
blood supply to Ciliary Body.
• It is formed by the Long posterior ciliary
artery and short anterior ciliary artery.
• Nerve Supply is by the nasociliary branch of
the 5th cranial nerve.

12. Clinical Pearls
• Blockage of outflow of aqueous
after production from the ciliary
body can occur at many levels and
cause a rise in Intra-Ocular
Pressure.
• Decreased production of aqueous
humor from the ciliary body can
lead to Phthisis Bulbi.
• In controlled glaucoma, Diode laser
cyclophotocoagulation (DLCP ) is
done, which destroys the ciliary
body and hence reduces aqueous
humor production, leading to
decrease in IOP

13. Thank You