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Eyes
Adapted from Mosby’s Guide
to Physical Examination, 6th Ed.
Ch. 11
Development
• By 2-3 months…
– Voluntary control of eye muscles
– Lacrimal ducts carry tears into nasal
meatus
• By 8 months…
– Can differentiate colors
• By 9 months…
– Eye muscles coordinate; a single image
is percieved
Visual Development
• Be familiar with Table 11-1(Mosby)
Chronology of Visual Development
Infant Eye Exam - Tips
• Often shut their eyes tightly
– Difficult to separate the eyelids
To encourage the infant to open their
eyes…
– Use a dimly lit room
– Hold the infant upright, suspended under its
arms
– Have parent hold infant over a shoulder
Infant Eye Exam - Tips
Even when the infant is crying, you
may get a glimpse at the eyes.
• Note anything you see…
–
–
–
–
Symmetry
Extraocular muscle balance
Red reflex
Etc.
Infant Exam
Inspect External Eye
• Size of eyes
– Small or different sized eyes
• Eyelids
– Epicanthal folds
• Asian populations
• Down syndrome
– Position
– Swelling
• Slant of palpebral fissures
Inspect the level of the eyelid
covering the eye…
To detect the “Setting Sun Sign”…
– Rapidly lower the infant from upright
to supine position
– Look for sclera above the iris
Differentials include:
– Expected variant in newborn
– Hydrocephalus
– Brainstem lesion
Note distance between
the eyes…
• Hypertelorism
(widely spaced eyes)
– may be associated
with mental
retardation
Strabismus?
Exoptropic vs. Esotropic
Tests include:
• Corneal light reflex (Hirschberg’s Test)
• Cross-Cover Test
• Cover-Uncover Test
Corneal Light Reflex
(Hirschberg’s Test)
• Child stares at a penlight about 30
cm away
• Doctor looks at the reflection from
each cornea
– In relationship to the pupil
Normal: symmetrical
Strabismus: asymmetrical
Cross-Cover Test
• Patient stares at penlight
• Doctor covers one eye and
observes the uncovered eye for
movement
Normal: no movement
Exotropia: moves lateral to medial
Esotropia: moves medial to lateral
Cover-Uncover Test
• Patient stares at the penlight
• Doctor covers one eye and then
observes as it is uncovered
Normal: no movement (remains fixed
on the light)
Exotropia: eye moves lateral
Esotropia: eye moves medial
Inspect
• Sclera
• Conjunctiva
• Pupil
– Coloboma?
• Iris
– Brushfield spots?
CLINICAL NOTE
• A newborn’s eyelids may be swollen
or edematous, accompanied by
conjunctival inflammation and
drainage
– Consequence of routinely administered
antibiotics
Beyond the newborn period…
• Redness
• Hemorrhage
• Discharge
• Granular appearance
…may indicate infection, allergy, or
trauma.
Cranial Nerves II, III, IV, VI
“Vision is grossly examined
by observing the the infant’s
preference for looking at
certain objects.”
Cranial Nerves II, III, IV, VI
1. Expect the infant to focus and
track through 60 degrees
2. Optical blink reflex
–
–
Shine a bright light at the infant’s eyes
Note the quick closure of the eyes
and dorsiflexion of the head
3. Corneal light reflex (Hirschberg’s)
Fundoscopic Examination
• Deferred until 2-6 months
– Very difficult to conduct on a newborn
or young infant
– Unless there is a need
• premature infant – visual problems
Red Reflex
*Should be elicited in every newborn
• Observe for opacities, dark spots, or
white spots within the circle of red
glow
 Congenital cataracts
 Retinoblastoma
Exam Recommendations
for Primary Care Physicians
Newborn – 3 months
Screening Method
Require Further Evaluation
Red reflex
Abnormal
Asymmetric
Corneal light reflex
Asymmetric
Inspection
Structural abnormality
6 months – 1 year
Screening Method
Require Further Evaluation
Red reflex
Abnormal or Asymmetric
Corneal light reflex
Asymmetric
Differential
occlusion
Failure to object equally to
covering each eye
Fix and follow with
each eye
Failure to fix and follow
Inspection
Structural abnormality
~3 years old
Screening Method
Require Further Evaluation
Visual acuity
<20/50; 2 lines of difference
between the eyes
Red reflex
Abnormal or asymmetric
Corneal light reflex; Asymmetric; ocular
Cover-uncover
refixation movements
Failure to appreciate
Stereoacuity
random dot stereogram
Inspection
Structural abnormality
~5 years old
Screening Method
Require Further Evaluation
Visual acuity
20/30 or worse
Red reflex
Abnormal or asymmetric
Corneal light reflex; Asymmetric; ocular
Cover-uncover
refixation movements
Failure to appreciate
Stereoacuity
random dot stereogram
Inspection
Structural abnormality
Child Exam
Children
• Inspect the external eye structure
(same as infant)
–
–
–
–
–
Size of eyes
Eyelids
Palpebral fissures
Distance between eyes
Strabismus
Inspect
•
•
•
•
Sclera
Conjunctiva
Pupil
Iris
Beyond the newborn period…
• Redness
• Hemorrhage
• Discharge
• Granular appearance
…may indicate infection, allergy, or
trauma.
Visual Acuity – Younger Children
• Observe play with toys
– Stacking, building, or placing objects
inside of others
If tasks are performed well, vision
difficulties are unlikely.
Visual Acuity
*Usually ~3 years of
age
• Tested when child
can cooperate with
the Snellen* E game
– Ask which way the
“legs” are pointing
*Also available with
different shapes
Snellen E Chart – Tips
• Allow the child to practice following
instructions before you administer
the test
– Instruct the child to point finger in the
direction of the legs of the E
• Have parent assist with covering one
eye
Snellen E Chart
REMEMBER:
*Test each eye seperately
*With and without corrective lenses
20/25 +2
• Means that they can read all on the 20/25
line and 2 from the 20/20 line.
Anticipated Visual Activity
Age
Visual Acuity
3 years
20/50
4 years
20/40
5 years
20/30
6 years
20/20
“When testing visual acuity in the
child, any difference in the scores
between the eyes should be
detected.”
• A 2 line difference (20/50 and 20/30)
may indicate amblyopia
– Reduced vision in an eye that appears
structurally normal
– In strabismus, the eye may be “unused”
Extraocular Movements
• Six cardinal fields of gaze
• Peripheral vision
– Parent may hold the child’s head still
– Use a teddy bear or toy
– Have child sit on parent’s lap
Fundoscopic Exam – Child
• PATIENCE!
– often unable to keep eyes still and
focused on a distant object
• May want to do the exam with the
patient supine…
Fundoscopic Exam – Supine
• Child laying supine on the exam table
with head near the end
• Stand at the end of the table
• Use Rt. eye to examine the child’s Lt.
NOTE:
– Retinal findings will appear upside down
– Inspect the optic disc, fovea, and vessels as
they pass by
Fundoscopic Exam – Tips
• Do not hold the child’s eyelid open
forcibly
– Leads only to resistance
• Often results are better when the
child sits on the parent’s lap
Common Conditions
Strabismus
Eyes do not focus on an object
simultaneously…
concern of amblyopia developing
Paralytic
• Impairment of extraocular muscles or their nerve
supply
Nonparalytic
• No primary muscle weakness
• Can focus with either eye but not both
simultaneously
Pseudostrabismus
• Symmetrical corneal light
reflex
• Common in Asian and
Native American
populations
• Disappears by 1 yoa
Strabismus (esotropic)
• Asymmetrical light reflex
Coloboma
“Keyhole pupil”
• Loss of functional pupil
• Often associated with other
congenital abnormalities
Brushfield spots
• White specks in a linear pattern
around the circumference of the iris
– Strongly suggests Down syndrome
Congenital Cataracts
• Requires a full metabolic, infectious,
systemic, and genetic workup…
Common causes:
– Infectious diseases
–
–
–
–
• TOxoplasmosis, Rubella (MC),
Cytomegalovirus, & Herpes
Hypoglycemia
Trisomies
Prematurity
Etc.
Retinoblastoma
• Congenital malignant tumor (retina)
• <2 years old
Initial sign: “white” reflex
(aka cat’s eye reflex)
Fundoscopic exam
– Ill-defined mass
arising from the
retina
– Chalky-white areas
of calcification
Horner Syndrome
• Interruption of sympathetic nerve supply
to the eye
– Clinical presentation:
• Ipsilateral miosis (constriction)& mild ptosis
– Causes:
• Operative trauma
• Mediastinal tumors
• Metastatic tumors
• Bronchogenic carcinoma
Congenital Horner Syndrome
• Damage to the lower brachial plexus
(birth trauma)
• Sometimes seen with Klumpke’s Palsy
Retinopathy of Prematurity
• Blood vessels are straightened and
diverted temporally
• Cicatricial changes may be severe
– Retinal detachment
– Glaucoma
– Blindness
Retinal HemorrhagesShaken Baby Syndrome
• Multiple hemorrhages
Whenever retinal hemorrhages are
seen, you must suspect infant abuse