Ophthalmology

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Paediatric Ophthalmology
Glen Gole
Dept of Ophthalmology,
Royal Children’s Hospital, Brisbane
Dept of Paediatrics and Child Health,
University of Qld
[email protected]

VISUAL ACUITY
Defn: The resolving power of the eye

SHERIDAN GARDINER TEST

Visual Development
•  Requires clear images and aligned eyes
during early childhood
•  The two eyes compete with one another from
birth to make connections on the cortex
•  Vision at birth 6/480, 6/36 at 6 mos, 6/9 at
age 3
•  Fusion and stereopsis develop at about 4
mos of age (coincident with foveal
maturation)
•  Can occur only up to age 8 years

Amblyopia
•  Amblyopia: Poor vision due to abnormal
visual experience in early life
•  Prevalence is about 3%
•  Prevalence is decreased when screening and
early intervention are instituted (supported by
RCTs)
•  Prevalence is higher in medically
underserved populations

ANISOMETROPIA
• A difference in the refractive
error of the two eyes
• Can be easily detected
using the Bruckner reflex

STRABISMUS (SQUINT)

SQUINT

DEFN:
Misalignment of the Eyes
TERMINOLOGY:
Eso
Convergent
Exo
Divergent
-Phoria
A Latent Squint
(held in place by fusion)
-Tropia
A Constant Squint

AMBLYOPIA

REFRACTIVE
ERRORS

SQUINT TYPES
• 

Esotropia: A constant convergent squint (crossed eyes)
• 
• 

• 

Exotropia: A constant divergent squint
• 
• 

• 

a) Infantile Esotropia
b) Acquired Esotropia

a) Intermittent
b) Constant

Others
• 
• 
• 

a) IV N palsy
b) III N palsy
c) Vertical squints

Infantile Esotropia
• 
• 
• 
• 
• 

Not truly congenital
Onset usually between four and six months of age
Typically have moderate to large angle of squint
Treatment is surgical, anytime after six months
Early surgery=better chance for binocularity

DETECTION OF SQUINT
• 
• 
• 
• 
• 

External Appearance
Asymmetry of Corneal Light Reflexes
(Hirschberg Test)
Cover Test
Bruckner Test
Amblyopia

Corneal light reflections
(reflexes)

BRÜCKNER REFLEX

• 

Comparison of fundus red reflexes when viewed simultaneously at
arms length through direct ophthalmoscope

• 

Good for detecting small angle squints and amblyopia

• 

Sensitivity 86% and specificity 68% for detecting amblyopia risk factors

• 

In children with amblyopia, 95% sensitive

MANAGEMENT OF SQUINT
• 
• 
• 
• 
• 

Correct Diagnosis of Type
Exclude of Treat Systemic or Ocular
Disease
Correct Refractive Errors
Treat Amblyopia
Surgery

Strabismus Management
• 
• 

Necessity for follow up throughout
childhood
If glasses don’t straighten eyes,
surgery is necessary in order to
maximise binocular potential

Aims of Strabismus
Surgery:
To allow binocularity to develop
To restore binocularity
To improve appearance

Measuring the misalignment

Ophthalmia Neonatorum
Any severe conjunctivitis in the
newborn period

Aetiology
• 

• 
• 
• 

Bacterial - N Gonorrhoeae
- Ps aeruginosa
- Staph aureus
- Str pneumoniae
- H influenzae
Chlamydia
Viral-HSV type II
Chemical

Investigation
• 
• 
• 

Conjunctival swabs (culture/Gram stain
Conjunctival scrapings (Chlamydia PCR)
Immunofluorescent studies (HSV/Chlamydia)

Blockage of the
Nasolacrimal Duct

CHILDHOOD GLAUCOMA

Infantile Glaucoma
•  Affects 1/8-10,000 children
(M East 1/2,500)
•  Primary congenital
glaucoma usu sporadic
80%>recessive, rarely
dominant
•  60% present by 6/12,
80% by 1
•  2/3 male, 2/3 bilateral
•  GLC3 gene-2p21, 1p36

End Stage Infantile Glaucoma

LEUKOCORIA

LEUKOCORIA
(WHITE PUPIL)

• 
• 

Commonest cause - Congenital cataract
Must always exclude Retinoblastoma

CONGENITAL CATARACTS
• 
• 
• 
• 

Hereditary
Metabolic
Infectious
Systemic Disease

Early Surgery
•  Early surgery definitely gives
better results
•  Operate around 6-8 weeks
•  Allows time for optical
correction before amblyopia
develops (12 weeks)
•  But surgery before 4 weeks
increases glaucoma risk

Optical Correction

• 
• 
• 
• 
• 
• 

Glasses-poor results
Contact lenses- currently best option
70-80% of bilateral aphakes-6/18 or better
50% on monocular aphakes-6/18 or better
Not for “dull”, diabolical, distant or dirty”
Allow changes in lens power

• 

IOL’s-not for infants

Every Newborn Child
should have the Fundus
(Red) Reflex examined
before discharge from the
nursery.

Retinoblastoma
•  Malignant eye cancer
•  occurs 1/18,000 live
births
•  Often results in loss of
eye if tumour growth
can not be controlled
•  many tumours now
treatable with laser

RETINOBLASTOMA
PRESENTATION

RETINOBLASTOMA

•  Leukocoria
•  Strabismus
•  Others

•  Recessive Gene
•  ‘Two Hit’ Hypothesis
•  Dominant Inheritance

RETINOBLASTOMA
•  Multiple Tumors in One Eye
•  Bilateral Involvement
•  One Tumor in One Eye

Germinal
Mutation
Somatic
Mutation

Non-Accidental Injury
(NAI)

NAI
• 
• 

Inconsistent history
History inadequate to explain degree of
injury

Childhood Blindness
• 
• 
• 
• 
• 

Childhood Blindness

Third World
• 
1.5 million blind
• 
75% of causes preventable or curable
Half million new cases per year
• 
60-80% die within two years of blindness • 
• 
• 

Developing World-mostly preventable
measles, xerophthalmia

Developed World
Cerebral vision impairment
Retinopathy of prematurity
optic nerve hypoplasia

PAEDIATRIC LOW VISION CLINIC-QUEENSLAND
List of Major Causes of Low Vision (%)
1974-81
(N=468)

1982-86
(N=283)

1986-89
(N=295)

1990-92
(N=221)

1993-94
(N=125)

1996-99
(N=242)

2.4

9.9

14.2

24.9

21.5

31

4.1

5.6

4.8

4

21.5

7.4

Albinism

7.8

7.8

7.8

7.6

10.8

7.8

Optic Atrophies

11.3

11.3

11.9

5.3

9

9.1

Retinopathy of Prematurity
Maculopathies
(incl Stargardt’s Disease)

2.6

2.8

5.8

5.8

9

4.9

3.9

2.1

5.4

4.9

4.5

2.1

Retinitis Pigmentosa

2.6

0.7

1.4

4

4.5

4.9

Coloboma

0.9

1.8

2.4

3.1

3.6

2.5

Optic Nerve Hypoplasia

1.9

3.1

5.1

3.1

3.6

2.4

Congenital Cataracts

15.8

10.2

11.9

3.1

2.7

1.2

Myopia

1.7

3.1

3.6

6.2

2.7

4.1

Nystagmus
Retinopathies
(incl. Lebers, rod monochromatism

16.5

17

8.1

13.8

1.8

8

1.9

2.8

3.4

1.8

1.8

8.6

Ectopia Lentis

4.5

3.2

3.4

1.3

Rubella
Others

8.4
13

2.2
16.3

1
10.5

0.4
10.5

Condition
Cortical Vision Impairment
(incl. Hemianopia)
Aniridia/structural defects
(incl. aphakia)

1.2
12.5

3.3

Poor Vision in Childhood

Apparently Blind Child

Presentation:
• 
• 
• 
• 
• 

Failure of visual development
Family history
Nystagmus
Strabismus (squint)
White pupil

• 
• 
• 
• 
• 

Anterior Visual Pathway Disease
(Nystagmus)
Posterior Visual Pathway Disease (CVI)
Delayed Visual Maturation
Generalised Developmental Delay
Autism

Cortical Vision Impairment
•  Poor vision due to damage or non
development of the occipital cortex
•  Now commonest cause of impaired
vision in childhood (30% in Qld)
•  Largest subgroup is premature infants
•  However, cortex is only rarely damaged
in isolation

Neural Development

Cerebral Vision Impairment-a better
term
•  Poor vision due to damage or non development of
the visual areas of the brain (40% of brain has some
visual function)
•  More accurately reflects the often widespread nature
of injury to the visual system, not just cortex
•  Dutton GN, Jakobsen LK
Cerebral visual impairment in children
Semin Neonatol 2001Dec;6(6);477-485

Child with Poor Vision
• 
• 
• 
• 
• 
• 

Acute intervention (PLVC)
Mobility
Low Vision Aids
Counselling for Parents
Medicolegal issues
Whole of life cost $1m

Visual Problems in Premature Infants
• 
• 
• 
• 
• 
• 

Cerebral Vision Impairment
Retinopathy of Prematurity (ROP)
Amblyopia
Refractive Errors
Strabismus
Glaucoma (acute and late after ROP)

Visual Problems in Premature Infants
• 
• 
• 
• 
• 
• 

Cerebral Vision Impairment
Retinopathy of Prematurity (ROP)
Amblyopia
Refractive Errors
Strabismus
Glaucoma (acute and late after ROP)

Retinopathy of Prematurity (ROP)
A retinal vascular disorder
characterized by abnormal
vasoproliferation in the retina of
premature infants.

Retinal Vascularization
•  Begins at 16 wks
gestation
•  Usually complete by
36-38 wks gestation
•  Proceeds from disc as
wave of mesenchymal
cells which then lays
down the primitive
capillary network

Pathogenesis of ROP

L. MacKeene - Toronto

41

L. MacKeene - Toronto

42

Retinopathy of
Prematurity

•  Laser cures over
90% of affected
infants
•  Diode laser can be
used in nursery
•  Blindness now <1%
of premature infants

Diode Laser treatment of Zone 1 ROP

Retinopathy of Prematurity
•  The only children now developing severe
ROP are extreme premature infants (eg 17
weeks premature) who are likely to have
multiple handicaps
•  We now understand many of the underlying
molecular mechanisms
•  Treatments to slow blood vessel growth by
non surgical means will be developed within
the next few years

Gene Therapy in Ophthalmology
•  87 eye diseases caused by a specific genetic
defect- 20 genes have been identified
•  Many of these disorders affect children eg
retinal dystrophies such as Lebers amaurosis
•  Inject good gene into the eye eg on a virus
carrier
•  Transplant into eye genetically modified cells
•  Animal and human trials are underway
•  Retinitis pigmentosa may become a treatable
disease within a decade

WHEN TO REFER TO AN
OPHTHALMOLOGIST

•  any sight threatening condition
•  If unsure about diagnosis
•  if condition is not responding as
it should
•  when encountering an
uncommon condition for the first
time
•  any child with a white pupil

Your professional tasks
•  Have a successful career and keep your
important relationships together-spouse,
children, friends.
•  Medicine is a long, demanding career, pace
yourself so you have something left for
yourself at the end.
•  Look after your colleagues and yourselfdrugs, alcoholism, depression and suicide
are professional hazards. None of us is
bulletproof-smell the roses when you can.

Retinopathy of Prematurity (ROP)
A retinal vascular disorder
characterized by abnormal
vasoproliferation in the retina of
premature infants.

Retinal Vascularization
•  Begins at 16 wks
gestation
•  Usually complete by
36-38 wks gestation
•  Proceeds from disc as
wave of mesenchymal
cells which then lays
down the primitive
capillary network

Pathogenesis of ROP

L. MacKeene - Toronto

41

L. MacKeene - Toronto

42

Retinopathy of
Prematurity
•  Laser cures over
90% of affected
infants
•  Diode laser can be
used in nursery
•  Blindness now <1%
of premature infants

Diode Laser treatment of Zone 1 ROP

Retinopathy of Prematurity
•  The only children now developing severe
ROP are extreme premature infants (eg 17
weeks premature) who are likely to have
multiple handicaps
•  We now understand many of the underlying
molecular mechanisms
•  Treatments to slow blood vessel growth by
non surgical means will be developed within
the next few years

VISUAL FUNCTIONING IN CVI
•  acuity fluctuates
•  notices moving objects more
than static objects
•  sees better in familiar
environments
•  lacks visual curiosity
•  tires easily during visual activities

RECOVERY FROM CVI
• 
• 
• 
• 
• 

Light perception
Colour vision
Movement
Form perception
Acuity

Retcam Screening
Very useful for telemedicine

Gene Therapy in Ophthalmology
•  87 eye diseases caused by a specific genetic
defect- 20 genes have been identified
•  Many of these disorders affect children eg
retinal dystrophies such as Lebers amaurosis
•  Inject good gene into the eye eg on a virus
carrier
•  Transplant into eye genetically modified cells
•  Animal trials are underway
•  Retinitis pigmentosa may become a treatable
disease within a decade

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