PUPILARY ABNORMALITY AND PHARMACOLOGIC TESTS.pptx

Pupillary Abnormality and Tests
Moderator Dr. Liya (MD. Asst.proph .)
Presenter Dr.Muez A.(1st year
ophthalmology Resident)
21/06/2010EC muezash21@gmail.com 1

Outlines
Features of normal & abnormal pupil
Overview of anatomy
Functions of the pupil
Afferent pathway defects
Efferent pathway defects
Anisocoria
Pharmacological tests
2
21/06/2010EC muezash21@gmail.com

PUPIL
 Window to the inner eye in the centre of the iris.
 Size determines the amount of light entering the eye.
 Controlled by the dilator and sphincter muscles of the iris.
3

• Normally there is one pupil in each eye.
• Rarely, more than one pupil.
• This congenital anomaly is called POLYCORIA.
• Normally, pupil is placed almost in the centre (slightly nasal) of the
iris.
• Rarely it may be congenitally eccentric ( CORECTOPIA )
4

 SHAPE : Normal pupil is almost circular in shape
 Oval in cases of acute congestive glaucoma, severe
brain disease
 Key hole shaped in cases of sector iridectomy
 The leading cause of a mis shapen pupil in an adult is
probably cataract surgery
 Iridodialysis P.Psynechia
5

CONT…
 Adherent leukoma
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Congenital Aniridia Axenfeld–Rieger Syndrome

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Coloboma Persistent Pupillary Membrane

COLOUR :
 Normally, it is greyish black.
• It becomes jet black in aphakia
• Greyish white: - cataract.
• Brown in brown nuclear cataract.
• Whitish(leukocoria): -
• Retinoblastoma
• pseudogliomas .
• Yellowish: - vitreous abscess (endo and
panophthalmitis).
• Greenish: - Acute congestive glaucoma.
• Reddish in albinos
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Size
 Average size
 At Dim light 4-8 mm
 At bright light 2-4 mm
 miotic pupils < 2mm
 mydriatic pupils > 8mm
The resting pupil size is
influenced by several
factors;
 the amount of ambient
light
 the status of retinal
adaptation
 the level of arousal
 the patient's age.
9

Cont..
Conditions that increase
pupilary size:
 Arousal
 Excitement
 Startle
 Elevated intraocular
pressure
 Extremely large pupils
 parasympathetic
pharmacologic blockade
Conditions that decrease
pupilary size
 in infants and elderly
 during sleep
 flaccid people
 black irides
Extremely small pupils
 pontine hemorrhage
 narcotic intoxication
 pilocarpine use
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Relevant Anatomy
Muscle tissue of the iris consists of
A. Sphincter muscle
B. Dilator muscle
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Sphincter
Muscle
 It is a narrow circular band, 1
mm wide
 close to the pupillary aperture,
surrounding the pupil on the
posterior aspect of iris.
 Supplied by
 Parasympathetic nerve
Dilator Muscle
 Radially disposed muscle
 extend from ciliary body to
pupillary margin
 Supplied by
 Sympathetic nerve
12

13

Functions of pupil
1. Window of light
2. It regulates the amount of
light entering the eye by
miosis in light and mydriasis
in darkness.
3. It improves VA by preventing
irregular refraction by
peripheral cornea and lens,
and increases the depth of
focus.
4. It allows passage of aqueous
humour
PUPILLARY
REFLEXES
 LIGHT REFLEX
 NEAR REFLEX
 DARKNESS REFLEX
 PSYCHOSENSORY
REFLEXES
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Light reflex
 In normal subjects, the direct
and consensual reactions
 almost identical in time,
course and magnitude.
 If both pupils are illuminated
simultaneously
 the constriction of each pupil
is greater than the constriction
noted when only one pupil is
illuminated
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PATHWAY OF LIGHT REFLEX
 Afferent and Efferent
pathways
1. First (sensory)
2. Second (internucial )
3. Third (pre-ganglionic
motor)
4. Fourth (post-ganglionic
motor)
16

2. NEAR REFLEX
 A synkinesis rather than a
true reflex
 Accommodation,
convergence &miosis
• occipital association
cortex corticofugal
pretectal{ventral side }
 Edinger-Westphal
nuclei
 motor nuclei of the
 medial rectus muscles
nuclei of CN VI.
• Efferent fibers same
general pathway the light
reflex,
• but their final distribution
(via the short ciliary
nerves) is to the ciliary
muscle
• There is no clinical
condition in which the
light reflex is present but
the near response absent.
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3. DARKNESS REFLEX
 Initial response to darkness is
Sympathetic activation, followed by
parasympathetic inhibition acting through the
Edinger-Westphal
 The pathways involved in dark reflex are presumably
 the same as those of light reflex
 redilatation at the end of long light stimulation
involves
 both relaxation of the sphincter pupillae and
contraction of dilator pupillae.
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4. PSYCHOSENSORY REFLEXES
 Is dilatation of pupil in
response to sensory and
psychic stimuli.
 Are not seen in a
newborn, but appear in
the first few days of life
 developed fully by the
age of 6 mo.
 Mechanism is very
complex and pathways
are unclear.
 The mechanism is a
cortical one and
apparently the pupillary
dilatation
 b/se of - a symp
discharge to the dilator
pupillae
 and an inhibition of the
parasymp discharge to
the sphincter pupillae.
19

ANISOCORIA
 Defined by a difference in the size of the two pupils of
0.4 mm or greater.
 Doesn’t occur in afferent pupilary pathway
 Physiologic
 Pathologic
 Horner syndrome
 Mechanical
 Adie tonic pupil
 Coulometer palsy
 Pharmacologic
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Physiologic anisocoria.
• Ocure in 20%
• Anisocoria Equal in Dim and
Bright Light
• If pupillary light reflex and dilation
are symmetric between both eyes
• most common cause of a
difference in pupil size of 0.4 mm
or more.
• Usually the difference in pupil
diameters is less
than 1.0 mm and can vary from
day to day
• Ptosis occurring on the side of the
smaller pupil
• Differentiation between
pseudo- and true Horner
syndrome is best done
• pahrmacologically
A. In dim light right pupil is larger than
the left.
B.In bright light both pupils constrict
normally.
C. After instillation of cocaine 4% to
both eyes, both pupils dilate

Anisocoria
Greater in Dim Light Greater in Bright Light
 Mechanical anisocoria
 Post trauma (including
surgery) or inflammation
can lead to adhesions
between the iris and the
lens
 prevent pupillary dilation
in conditions of dim
illumination
 Pharmacologic miosis
 pilocarpine may result in a
small, poorly reactive pupil.
 Physiologic anisocoria
 Iris damage
 miosis or mydriasis
 poor responses to light and
near stimulation
 does not respond to topical
pilocarpine (1% or 2%)
 thus mimics pharmacologic
mydriasis SLE
 recurrent angle closure
 Pharmacologic mydriasis
(Adrenergic)
 pupil is large,
 palpebral fissure is widened
 conjunctiva may be blanched
 Accommodation is not
impaired

AFFERANT PATHWAY DEFECTS
TOTAL AFFERENT PATHWAY DEFECT (TAPD) OR AMAUROTIC
PUPIL
 Caused by a complete optic nerve or retinal lesion
 Is characterized by :
 The involved eye is completely blind (i.e NLP)
 No direct & consensual light reflex on affected &
normal side respectively
 When the normal eye is stimulated, both pupils react
normally.
 In diffuse illumination, both pupils are equal in size.
 The near reflex is normal in both eyes.
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Amaurotic pupillary response
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RELATIVE AFFERENT PATHWAY DEFECT (RAPD) OR
MARCUS GUNN PUPIL
 It is the paradoxical response of a pupil to light
 Caused by an incomplete optic nerve lesion or a severe retinal
disease.
• central retinal artery occlusion or retinal detachment
• Optic neuropathy and RAPD do not cause anisocoria
• An RAPD is an extremely reliable indicator of optic nerve
dysfunction.
• Its absence shows lack of an optic neuropathy or bilateral
optic nerve involvement.
• Chiasmal lesions may produce an RAPD
• mild contralateral RAPD can result from optic tract lesions
• may result from media opacities such as cataract or vitreous
hemorrhage or from amblyopia.
 It is best tested by ‘swinging flashlight test’
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Swinging Flashlight Test
• Dim the ambient lighting.
. Ask the patient to fixate at distance
• Stimulate 1 eye for 2–3 seconds, and quickly move
across the bridge of the nose .
 Normally, both pupils constrict equally and the pupil to
which light is transferred remains tightly consrticted.
 If RAPD in one eye, the affected pupil will dilate
(paradoxical response) when the flashlight is moved from
the normal eye to the abnormal eye.
 This response is called Marcus Gunn Pupil.
 It is the earliest indication of optic nerve disease even in the
presence of a normal visual acuity.
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27

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There are many different methods to measure an RAPD in
clinic. A common method is using a qualitative +1-+4 grading
scale.
Grade +1: A weak initial pupillary constriction followed by
greater redilation
Grade +2: An initial pupillary stall followed by greater
redilation
Grade +3: An immediate pupillary dilation
Grade +4: No reaction to light – Amaurotic pupil

EFFERENT PUPILLARY DEFECTS
 Characterized by absence of both direct and
consensual light reflex on the affected side and
presence of both direct and consensual light reflex on
the normal side.
 On the affected side, near reflex is also absent and
pupils remains fixed and dilated.
29

COMMON CAUSES OF EFFERENT PUPILLARY
DEFECTS :
1. Brainstem lesions at the level of the superior colliculus
and red nucleus
2. Fascicular third nerve lesions. Compressive third nerve
lesions classically have pupillary involvement
20% of microvascular palsies will affect the pupillary
fibers.
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Cont…….
3.Lesions of the ciliary ganglion or short ciliary nerves.
4.Iris damage 2˚ to previous surgery or grossly elevated
IOP.
5.Drugs: inadvertent exposure to mydriatic agent such as
atropine is a common cause of fixed dilated pupil.
Pilocarpine 1% will constrict a dilated pupil 2˚ to a
neurological lesion but no effect on dilated pupil caused
by a mydriatic agent.
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TONIC PUPIL
• Damage to the ciliary
ganglion or short ciliary
nerves
• characterized by poor
reaction to light,
• sectoral palsy of the iris
sphincter
• accommodative paresis
• denervation cholinergic
supersensitivity
• strong and tonic
pupillary response to
near vision (light–near
dissociation) followed by
slow redilation

Causes Of Tonic Pupil :
A. Local tonic pupil
• Viral ciliary ganglionitis (e.g Herpes zoster)
• local ocular surgery, trauma, laser procedure, inflammation,
or ischemia
B. autonomic dysfunction
 diabetes mellitus, chronic alcoholism,
 dysautonomias, neurosyphilis, amyloidosis,
 sarcoidosis, the Miller-Fisher variant of Guillain
 Barré syndrome, or Charcot-Marie-Tooth disea
C. Idiopathic tonic pupil known as Adie pupil
70% of patients are female.
unilateral in 80% of cases
 second pupil may later become involved (4% per year).
 Holmes-Adie syndrome
diminished deep tendon reflexes
 orthostatic hypotension.
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• Slit lamp feauture
• Iris crypts stream toward
normal sphincter function,
• stroma bunches up along
the pupillary border
• stromal thinning even
atrophy
• As the damaged short ciliary
nerves regenerate,
• misguided accommodative
fibers sprout onto the iris
sphincter
• pupil recovers its ability to
constrict to accommodative
(or near) effort.

• However, pupillary
movement (both
constriction to an
accommodative stimulus
and subsequent redilation)
• difficulty refocusing
• The pupillary light reflex
remains severely impaired.
• usually resolve
spontaneously within a few
months of onset
• photophobia from a dilated
pupil is a problem
• dilute pilocarpine (0.1%)
helpful.

Testing
 0.125% pilocarpine
 Fixating at a distance ,
measure the pupil size
 Instill a drop of 0.125
pilocarpine in each eye
 After 60 minutes, the pupils
are reexamined,
 if parasympathetic
denervation is present, the
affected pupil will constrict
more than the normal pupil .
 80% of patients with a tonic
pupil show
cholinergic denervation
supersensitivity
Right tonic pupil
After 0.125 % pilocarpine

 Third nerve palsy
almost always accompanied by ptosis and limited ocular
motility.
 When the pupil is involved, an aneurysm at the junction of
the internal carotid and posterior communicating arteries
must be excluded
 If the pupil is spared and all other functions of the third
nerve are completely paretic,
aneurysm can likely be ruled out.
 Aberrant regeneration of the oculomotor
mydriasis and a synkinetic pupillary reaction.

PUPILLARY LIGHT - NEAR DISSOCIATION
Refers to any situation in which the pupillary near
reaction is present and the light reaction is absent.
38

 Afferent Visual Pathway
 Optic neuropathy is the most common cause of light–
near dissociation (unilateral or bilateral).
 damage to only the afferent limb of the
pupillary light reflex (optic nerve)
 the central near impulses remain unaffected.
 Midbrain
 result in midsize pupils with poor light response and
preserved near response.
 lesion spares the more ventrally path way.
 bilateral eyelid retraction (Collier sign),
 vertical gaze palsy, accommodative paresis

Argyll Robertson pupil
 Bilateral, miotic pupil with
irregular margins and are
asymmetrical.
 occurs in tertiary syphilis
 central nervous system.
 near response and subsequent
redilation are normal and brisk.
 distinguishes from bilateral
chronic tonic pupil
 Serologic tests for syphilis
 Other causes include :
- Diabetes
- Wernicke’s encephalopathy
- Encephalitis,
- Midbrain tumours
- Hereditary neuropathies
Bilateral light-near dissociation caused by
the dorsal midbrain syndrome: moderately
dilated pupils (above) with brisk near reflex
(below).
Small pupils < 2 m
Often irregular
Light reflex is absent
Iris atrophy
poor dilatation with mydriatics
Visual acuity is usually normal

• Aberrant Regeneration
• restores the near reflex but not the light reflex.
• tonic pupil syndrome
• traumatic injury or chronic compression of the
oculomotor nerve.
• medial rectus fibers and pupillary contraction occurs
during attempted adduction.
• synkinetic pupil movement can resemble light–near
dissociation.

42

SYMPATHETIC PARESIS
SYMPATHETIC SUPPLY OF EYE :
43

HORNER SYNDROME
CLINICAL FEATURES OF HORNER’S SYNDROME
 Ptosis –( usually 1-2mm )
 False enophthalmos
 Miosis – accentuated in
dim light
 Light and near reflexs are
normal
 Facial anhydrosis –if lesion
is below the superior
cervical ganglion
 Heterochromia irides –in
congenital Horner’s
syndrome or acquired
before the age of 1yr

LOCALIZATION OF HORNER’S SYNDROME
 CENTRAL HORNER’S SYNDROME
 ataxia, nystagmus, and
hemisensory
deficit
• Facial anhidrosis
(MRI) of the brain and upper cervical
cord
 PREGANGLIONIC HORNER’S
SYNDROME
• arm pain, cough, hemoptysis,
• Facial anhidrosis
• Pancoast syndrome) or in the
mediastinum
• thyroid mass, chest surgery, thoracic
aortic
aneurysms, or trauma to the brachial
plexus
• POSTGANGLIONIC HORNER’S
SYNDROME
• Numbness over 1stas well as2ndor3rd CNV divisions
• Double vision b/se of CN VI palsy
• Tumor of middle cranial fossa or cavernous sinus
• Forehead anhidrosis

Painful postganglionic Horner syndrome
carotid artery dissection .
• located around the temple and orbit, and may extend
to the throat.
• may have amaurosis fugax and altered taste
(dysgeusia).
• must be recognized , in the acute stage, MRI
intramural hemorrhage
 Cluster headache
Congenital Horner syndrome
birth trauma to the brachial plexus.
 Non traumatic Horner syndrome in infants and children
neuroblastoma arising in the sympathetic chain of the
chest. Imaging of the head, neck, and chest

PHARMACOLOGICAL TESTS
1. COCAINE 4% or 10%
• Rationale- cocaine blocks
NE uptake at postganglionic
sympathetic nerve endings
• Result – Normal pupil will
dilate but Horner pupil will
not . post cocaine
anisocoria of ≥ 1mm is
diagnostic.
• Eyes with iris
synechiae and a
mechanically immobile
pupil can cause false-
positive cocaine test
• SLE
Right Horner’s syndrome: the
right pupil failed to dilate while the
left eye dilated to 7 mm with 10 %
cocain

2. APRACLONIDINE 0.5% OR 1% :
• weak α1-adrenergic agonist action gaining popularity
– α1 receptors are upregulated in the denervated dilator pupillae
Denervation supersensitivity
• Result - Horner pupil will dilate
• ptosis improves or resolves
• but the normal pupil is unaffected.
• avoided for children younger than 1 year
• central nervous system depression
• acute respiratory arrest
• Once Horner syndrome is diagnosed, topical
hydroxyamphetamine (1%) can be used to localize
• enhances the release of presynaptic norepinephrine from an
intact third-order
48

2.HYDROXYAMPHETAMINE 1% :
 hydroxyamphetamine
potentiates the release of
NE from post ganglionic
nerve endings
• Result : in the
preganglionic lesion, both
pupils will dilate. In
postganglionic lesion,
Horner’s pupil continues to
constrict.
• Draw back
• high rate of false negative
results
• commercial preparations
difficult to obtain

Tectal (dorsal midbrain) pupils :
 Also known as Parinaud's syndrome
 eye movement and pupil dysfunction
 In dim light there is B/L mydriasis
which may be asymmetrical.
 vertical gaze palsy, and sunset sign
 compression of the vertical gaze
center at the rostral interstitial nucleus
of medial longitudinal
fasciculus (riMLF)
 In bright light, neither pupil constricts.
 On accommodation, both pupils
constrict normally.
 After instillation of pilocarpine 0.1% to
neither pupil constrict.
50

Benign Episodic Pupillary Mydriasis
 Also known as springing
pupil
 young, healthy individuals
who frequently have a
history of headache
 Episodic mydriasis last from
minutes to hours
 accompanied by mild
blurring of vision, periocular
discomfort, and headache.
 Each episode is self-
limited, and the condition
 has not associated with any
systemic or neurologic
disease.
 In dim light the right pupil is
larger than the left.

Two rare conditions of focal abnormality in iris
innervation may cause pupillary irregularity:
1. Tadpole pupil
• focal spasm of the iris dilator muscle
• causing apeaking of the pupil that lasts a few minutes.
• occur numerous times over several days or a week
and then disappear.
• mild condition in most patients, but a small
• testing for Horner syndrome is recommended.
2. Midbrain corectopia.
• In rare cases, eccentric or oval pupils
• rostral midbrain disease.
• incomplete damage of the pupillary fibers
• selective inhibition of iris sphincter tone.

REFERENCES
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THANK YOU!!!
54

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