The document discusses pupil function and abnormal pupil reactions. It covers: 1. The physiology of pupil constriction and dilation which is controlled by the parasympathetic and sympathetic nervous systems respectively. 2. How to examine pupils including observing size and shape, light reflex testing, swinging flashlight test, and near reflex testing. 3. Various diseases and conditions that can cause abnormal pupil reactions like Horner's syndrome, third nerve palsy, Adie's tonic pupil, and Argyll Robertson pupils. 4. Drugs that can cause mydriasis or miosis by affecting the parasympathetic or sympathetic pathways.

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