Paediatric Ophthalmology

Glen Gole Dept of Ophthalmology,

Royal Childrens Hospital, Brisbane Dept of Paediatrics and Child Health,

University of Qld

g.gole@uq.edu.au

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) DEFN: Misalignment of the Eyes TERMINOLOGY:

Eso - Convergent Exo - Divergent -Phoria A Latent Squint (held in place by fusion) -Tropia - A Constant Squint

SQUINT

AMBLYOPIA REFRACTIVE ERRORS

SQUINT TYPES

Esotropia: A constant convergent squint (crossed eyes) a) Infantile Esotropia b) Acquired Esotropia

Exotropia: A constant divergent squint 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)

BRCKNER 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 dont 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 (WHITE PUPIL)

LEUKOCORIA 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

IOLs-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

Leukocoria Strabismus Others

RETINOBLASTOMA

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

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

Childhood 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 (%)

Condition1974-81(N=468)

1982-86(N=283)

1986-89(N=295)

1990-92(N=221)

1993-94(N=125)

1996-99(N=242)

Cortical Vision Impairment(incl. Hemianopia) 2.4 9.9 14.2 24.9 21.5 31Aniridia/structural defects(incl. aphakia) 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 2.6 2.8 5.8 5.8 9 4.9Maculopathies(incl Stargardts Disease) 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 16.5 17 8.1 13.8 1.8 8Retinopathies(incl. Lebers, rod monochromatism 1.9 2.8 3.4 1.8 1.8 8.6

Ectopia Lentis 4.5 3.2 3.4 1.3 1.2

Rubella 8.4 2.2 1 0.4Others 13 16.3 10.5 10.5 12.5 3.3

Poor Vision in Childhood

Presentation:

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

Apparently Blind Child

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

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 yourself-drugs, 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

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