Iris

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Iris, ciliary body and choroid
Iris

The iris lies in front of the lens and the
ciliary body

It separates the anterior chamber from the
posterior chamber
Iris
• The stroma connects a sphincter muscle (sphincter
pupillae), which contracts the pupil
• A set of dilator muscles (dilator pupillae) which open it.
• Depending on the amount of light, the iris makes the pupil larger or
smaller.
Structure of iris

The iris consists stroma.

The back surface is covered by an epithelial layer two cells thick (the iris
pigment epithelium

The outer edge of the iris, known as the root, is attached to the sclera and
the anterior ciliary body
.
The iris and ciliary body together are known as the anterior uvea


Aqueous humour
Just in front of the root of the iris is the region
through which the aqueous humour constantly
drains out of the eye, with the result that diseases
of the iris often have important effects on
intraocular pressure, and indirectly on vision.
Blood supply and nerve supply


Constrictor muscles are innervated by parasympathetic fibers of the 3rd
cranial nerve
Dilator muscles are innervated by sympathetic fibers from the superior
cervical ganglion.
Diseases of iris
Disease of iris

Iritis

Iris (uveitis)


Heterochromic iris
Iris atrophy
Aniridia
Iris cyst

Iris melanoma


Inflammation of
the iris
Busscca nodule
Berlin nodule
Koeppe nodule
Aniridia



It is usually bilateral condition in which the whole of the iris is appeared to
be missing on external examination
The rudimentary iris, can be visible only by goniocopy
It is due failure of anterior growth and differentiation of the optic cup
Symptoms

Photophobia

Nystagmus

Defective vision
Treatment

Soft contact lens to reduce photophobia

Glaucoma responds poorly to treatment
Typical coloboma


The pupil is pear-shaped with broad base
towards the pupillary margin.
Isolated typical coloboma of the iris is
rare. It usually extends upto the ciliary
body.
Albinism

This is a hereditary disorder of absence or reduction of the melanin
pigmentation throughout the body.

The iris looks pink and translucent, owing to lack of pigment
The fundus appears orange pink in colour.

Heterochromic iris


It means the two irides show a significant difference in colour.
It may be congenital or acquired hepertic uveitis , trauma, acute attack of
angle closure glaucoma.
Ciliary body

It lies between iris and choroid

It contains ciliary muscle and ciliary
processes.

The ciliary muscle takes part in
accommodation

Ciliary process produce aqueous humor.

Aqueous is transparent fluid which nourishes
ocular structure
Flow of aqueous humor
Ciliary process
Posterior chamber
Pupil
Anterior chamber
Trabecular meshwork
Canal of schlemm
Collector channel
Episcleral veins
Blood and Nerve supply

Blood supply :
by branches of long posterior ciliary artery and
short anterior ciliary artery.

Nerve supply :
Naso ciliary branch of 5th cranial nerve
Choroid

The vascular sheet separates the sclera from the retina.
It is 0.25mm of thick at posterior pole and 0.1mm thick anteriorly

There are 3 layer in the choroid




Outer vessel layer
middle vessel layer
Inner chorio-capillaries
Diseases of choroid



Choroiditis
Choroidal detachment
Choroidal coloboma
Choroiditis

Acute multifocal placoid pigment epitheliopathy (AMPPE)
It is unilateral idiopathic disease affecting young adults.
It is subacute loss of central vision with typical deep,
cream colored placoid lesions

Investigations:
FFA

Treatment
No effective treatment
:
Serpiginous choroiditis

It is a rare, idiopathic, recurrent disease of the RPE and chorio-capillaries
disease.

Chorio retinal inflammatory lesion starts around the optic disc and spreads
towards in all directions with out any inflammtory cells in the vitreous.

Investigations: FFA
Treatment : No effective treatment

Blood and nerve supply



Short posterior ciliary arteries
Two Long posterior ciliary arteries
Seven anterior ciliary arteries
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