Pupil abnormolities & anomalies

By;-M. Shivaram11immo14

Optometry&vision sciences

Pupil;- an aperture located in the centre of the iris that allows light to enter the retina.

round in shape and relatively equal in size

size vary from 2 to 8mm in diameterNormal pupils range from 3 to 5mm in ambient light

conditions

Miotic pupils are less than 3mm

Mydriatic pupils are greater than 7mm

Pupil disordersMicrocoria

Megalocoria

Anisocoria

Polycoria

Correctopia

Microcoria (small pupil)

Differential diagnosis –pilocarpine drops, uvietis with synaechiae, Horner's syndrome.

Megalocoria: (large pupil)

Differential diagnosistraumatic iris damage, third cranial nerve palsypharmacological dilation (i.e. dilating drops), Adie's pupil iris rubeosis

More than one pupil is called as polycoria

Polycoria (multiple pupils)

Corectopia

eccentric displacement of pupil called corectopia

Pupil anomalies 1-Argyll Robertson pupil

2-Reverse argryll robertson pupil

3-Adie’s tonic pupil

4-Horner’s syndrome

5-(Marcus gunn pupil) RAPD

6-Amaurotic pupil

7-Hutchinson’s pupil

8-Paradoxical pupil 9-Hippus

1-Argyll Robertson pupil

Hallmark of neurosyphilis ,No reaction to

light but brisk response to near ,Pupil is

small & irregular in shape

Diff-diagnosis;- encephalitis,parinauds syndrome

2-Reverse argryll robertson pupil

In this accommodation and reflex on the pupil is absent

causes;- Diptheria&

tumors at carpora quadrigemina

3-Adie’s tonic pupil

occurs mainly due lesion in the ciliary ganglions.

This lesion is thought to be caused by denervation of the post

ganglionic nerve supply to the sphincter and ciliary muscle

affected eye is dilated and reacts poorly to light (poor direct and consensual response)

Diff-diagnosis;-herpes zoster

opthalmicus,

adies syndrome

4-Horner’s syndrome

Horner's syndrome is due to damage or blockage of

the path of the sympathetic nerve which travels

through the neck and brain from the affected eye.

total or partial interruption of the sympathetic

pathway.

It consist of anisocoria miosis, ptosis &

enophthalmus and decrease in the facial sweating on

the affected side.

5-(Marcus gunn pupil) RAPD

It is due to the conduction defect of the optic nerve- particularly the

afferent fibers are defective

.In this, both the pupils will dilate a little when the abnormal eye is

stimulated.

The affected eye constricts less & redilates more than a normal eye. The

effected eye has a greater consensual response coming from the normal

eye than direct.

DIFF diag;- opticnerve tumors, retirobulbar neuritis

RAPD-- +

6-Amaurotic pupil (leucocoria)

A pupil in an eye that is blind because of ocular or

optic nerve disease and that contracts in response

to light only when the normal eye is stimulated with

light white pupillary reflex indicates abnormmal

red reflex indicates normal.

Causes: congenital cataract, retinoblastoma, ROP, toxocaris

7-Hutchinson’s pupil

due to the compression of the 3rd

nerve which is due to the meningeal

hemorrhage at the base of the brain.

It may also be due to central nervous

system lesion that compresses the

optic nerve. Dilation of one pupil when

the other pupil is constricted

(unilateral pupil dilation)

8-Paradoxical pupil

Parodoxicall pupil has a intresting reaction whereNormally pupil should constrict when light shown but in this condition

Lights on - pupil dilatesLights off -pupil constricts There is no particular causes for this but due to retinal & neuronal disorders it may happens Research studies are going on this pupillary reflex

Video to watch pupillary response

https://www.youtube.com/watch?v=yMvJfmJaTjM

9-Hippus

Irregular rythamatic visible pupillary oscillations 2mm / more in amplitude

irregular dilating & constricting movements are observed

Also called as pupillary athestosis

causes;- myasthenia gravis

References;-clinical ophthalmology by Jack j Kansky

6th –edition

Pediatric ophthalmologyby kenneth & wright-3rd edtn

THANK YOU