1. Abnormal Pupil Reactions
Hatlan Alhatlan
211525898

2. Pupil ?

3. Function of The Pupil
• The pupil serves an important function to the eye ,
as it controls the amount of the light that enters the
eye , and it does so by the help of the Iris:
• Sphincter muscle(constrictor) Dilator muscle
(Circular) (Radial)

4. Physiology of The Pupil
• Knowing the physiology
is must :
• The parasympathetic
pathway :controls the
constrictor pupillae
muscle , serves as the
pupillary light reflux :
• Also as near , orbicularis
and trigeminal

5. The Pupillary light reflux pathway :
Afferent pathway -
1-optic disc/nerve
2- optic chiasm
3- optic tract
4-the pretectal nucleus (lying in the dorsal midbrain).
Efferent pathway: (The parasympathetic)
1- Edinger-Westphal nucleus
2- the third cranial nerve out to
3-the ciliary ganglion
4-short ciliary nerves to both constrictors of the eye.

6. The Sympathetic Pathway
• The sympathetic
pathway controls the
dilator papillae muscle :
• For withdrawal ,
emotional fear and
vestibular reflex.

7. The pathway of The Sympathetic
• -The central first neuron begins in the posterior
hypothalamus, the ciliospinal center (C8-T2)in the
cervical spinal cord
• -The preganglionic second neuron
• Through sympathetic trunk to the superior
cervical ganglion.
• -The postganglionic third neuron extends a
neural plexus along the internal carotid artery,
ophthalmic artery, and long ciliary nerves to the
dilator pupillae muscle .

8. Let’s Start to evaluate the Pupil
• General examination of the patient
• Provide helpful clues as to what is going on,
particularly where there is an underlying
neurological cause.
• Telltale neck scar and associated ptosis in
patients with Horner's syndrome or a
neurosurgical scar in patients with a 3rd nerve
palsy.

9. Pupil Examination
• Important terminologies :
• Examination consists of four steps :
AnisocoriaIsocoria
Unequal pupils size
(efferent or
unilateral)
Equal pupils size
(afferent or
bilateral)

10. 1-Pupil Observation
• Start by a general observation, noting
1. The shape
2. The size of the pupil in ambient bright light.
Size is measured in millimetres and the
normal pupil ranges from 1-8 mm.
3. The symmetry.

11. 2-Light reflex test
• Used to assess the integrity of the pupillary
light reflex pathway.
• Direct light reflex :
The examined eye is constricted when the light
is shown.
• Indirect (consensual) light reflex :
The fellow eye will constrict.
(don’t stand in the front of the patient!!)

12. Indirect Light Reflex Test

13. 3- Swinging Flashlight Test
• Also known as (Marcus gunn test).
• Used to compare between direct and
consensual light reflex.
• It’s preformed by equal exposure of light to
each eye.
• Normally both pupils should be of the same
size and constricted.
• Abnormally if the pupil dilate if light is shown.

14. • That’s caused by withdrawal reflex of the
fellow eye.
• Called as RAPD (relative afferent pupillary
defect).

15. Near Reflex
• Used to test accommodation.
• Preformed by asking the patient to fixed at
distant the to bring it to a near object (arm’s
length).
• Normally the pupil will have a brisk
constriction.
• Near-light dissociation =significant better
pupillary near reflex than light reflex.

16. Normal Pupil Reactions
• Will be :
PERRLA, -MG
•Pupils Equal Round and
Responsive to Light and
Accommodation
•Negative Marcus Gunn response

17. Diagnosis Keys
• Determine which pupil is abnormal.
• Search for associated signs.
Disorders of the pupil may result from:
• Ocular disease.
• Disorders of the controlling neurological
pathway.
• Pharmacological action.

18. Anisocoria
• This is physiological in about 20% of people.
• How to assess it :
• An affected Large Pupil has poor constriction
in a well lit room.
• An affected small pupil has poor dilatation in
well lit room.

19. The abnormally reacting pupil
1- Light reflex test :
From severe optic nerve
damage(transection)
The patient will be blind in
one eye .
No reaction when the
affected side is
stimulated.
Opposite (Isocoria)
(fellow)

20. The abnormally Reacting Pupil
2- Swinging flashlight test
:when the pupil exhibits
an RAPD, it is described
as a Marcus Gunn pupil.
It suggests:
• Optic nerve disease,
central retinal artery or
vein, A mild RAPD may
also occur
in amblyopia .

21. The abnormally Reacting Pupil
• 3- Near light reflex :
• (light-near dissociation)
• Unilateral :afferent
conduction defect, Adie
pupil, herpes zoster
ophthalmicus.
• Bilateral : neurosyphilis,
diabetes, myotonic
dystrophy, Parinaud's
dorsal midbrain

22. Diseases affecting the pupils
• Congenital :
1. Aniridia : bilateral
absence pupil.
(Glaucoma)
2. Coloboma : partial
absence of pupil.
3. Leukocoria : White
pupil (retinoblastoma
or congenital cataract)

23. Diseases affecting the pupils
• Acquired :
1. Pseudoexfoliation
syndrome :grey-white
fibrogranular extracellular
matrix material deposited on
the anterior lens.
2. Sphincter tear: due to
trauma
3. Synechiae : post. between
iris +lens or ant. Between
iris and cornea.

24. Diseases affecting the pupils
• Neurological :
1- Horner’s syndrome :
disruption of the sympathetic
nerves supplying the eye.
Triad of :
• Partial ptosis (upper eyelid
drooping).
• Miosis (pupillary constriction).
• Enophthalmos .
• (Normal pupillary reaction)
• Causes :
Many causes :
1. Central : Multiple
sclerosis, spinal cord
tumors Syringomyelia.
2. Preganglionic:
Pancoast's tumour
3. Postganglionic : internal
Carotid dissection

25. Horner’s syndrome :

26. 2- 3rd cranial nerve palsy :
• Fixed and dilated pupil not reacting to light .
• Many causes at base of skull.
• Ptosis and 4 EOM paralysis , except lateral
rectus and superior oblique.

27. 3rd Nerve Palsy

28. 3- Adie's tonic pupil:
Tonically dilated pupil
reacts much
significantly to
accommodation more
than light.
Caused by infection to
ciliary ganglion.

29. 4-Argyll Robertson pupils:
Caused by
neurosyphilis.
They are characterized by
bilateral (usually
asymmetrical) small,
irregular pupils showing
a light-near
dissociation.
Difficult to dilate.

30. Drugs Affecting Pupil
•Mydriatics (bilateral or
unilateral )
• Topical : sympathomimetics
(eg, phenylephrine,
adrenaline) and
antimuscarinics (eg,
cyclopentolate,
tropicamide, atropine).
• Systemic:
sympathomimetics (eg,
adrenaline (epinephrine))
and antimuscarinics (eg,
atropine).
•Miotics (bilateral or unilateral)
• Topical : muscarinic
agonists (eg, pilocarpine).
• Systemic: opiates (eg,
morphine and
organophosphates).

31. Remember :
• Take a good history to help exclude an ocular
cause for the pupillary changes and to see if a
medical condition exists which may contribute
to the pupillary problem.
• Determine whether it is the small or the large
pupil that is abnormal.
• Search for associated signs that may help
make a diagnosis.

32. Resources :
• http://www.patient.co.uk/
• Lecture notes on ophthalmology 9th edition.

33. Thanxxxxxxxxxx