Penaksiran dan Diagnosis Kanak-kanak Bermasalah

Penglihatan

Dr Safinaz Mohd KhialdinPensyarah & Pakar Oftalmologi

Jabatan OftalmologiPPUKM

• Visual impairment or low vision • reduction in vision that cannot be corrected

with standard glasses or contact lenses • reduces a person's ability to function at certain

or all tasks

Visual Impairment

• Functional limitation of the eye(s) or visual system

• Can manifest as• Reduced visual acuity • Reduced contrast sensitivity• Visual field loss• Photophobia• Diplopia• Visual distortion

Visual Impairment

• Clearness of vision• dependent on the

sharpness of the retinal focus within the eye

• the sensitivity of the interpretative parts of the brain.

Visual acuity

VISION TESTING IN CHILDREN

Contrast sensitivity

• How well your eyes function in dim light • How well you can distinguish objects from

similarly colored or shaded backgrounds.

• The total area in which objects can be seen in the peripheral vision while you focus your eyes on a central point.

Visual field

PHOTOPHOBIA – glaring

DIPLOPIA – double vision

VISUAL DISTORTION

• Definition:• Visual impairment : • visual acuity of less than 6/18, but equal or

better than 3/60 in the better eye• Visual field less than 20 degree from fixation

• Blindness: • visual acuity is less than 3/60 in the better eye• Visual field less than 10 degree from fixation

Visual Impairment

6/60

6/18

• HISTORY TAKING – SYMPTOMS

• EXAMINATIONS – SIGNS

• INVESTIGATIONS – CONFIRM DIAGNOSIS

EVALUATION & DIAGNOSISOF VISUAL IMPAIRMENT

• Ocular History• Diagnosis and onset of symptoms• Past, current, or planned surgeries or

treatments• Stability of vision• Family history of eye disease• Previous history of eye disease or vision

problems• Current or previous use of spectacles,

contact lenses, or low vision aids

EVALUATION & DIAGNOSIS: HISTORY

• Visual Functioning• Ability to read print and specific reading

needs (schooling)• Intermediate visual ability and needs (e.g.,

use of computer, reading music)• Distance visual ability and needs• Photophobia, glare sensitivity, and lighting

requirements

EVALUATION & DIAGNOSIS: HISTORY

• Medical History• General health review• Current medications• Hearing impairment or other disability• Developmental delay

EVALUATION & DIAGNOSIS: HISTORY

• EXAMINATION• Visual acuity• Visual field• Refraction• Eye movement• Detailed examination of the eye structures

EVALUATION & DIAGNOSIS: EXAMINATION

• To confirm eye problem• Ultrasound• CT scan

• To assess visual impairment• Contrast sensitivity testing• Colour vision testing• Visual evoked potential

EVALUATION & DIAGNOSIS: INVESTIGATIONS

Eye problems in children

Importance Early detection & treatment of peadiatric

ocular disease is critical Delay in diagnosis results in irreversible vision

loss Assessment should begin at birth

• Eye pathology : Structural impairment or damage to one or more parts of the eye

• Refractive errors: or an inability of the eye to sharply focus images on the back of retina

• Cortical visual impairments: damage to the part of the brain that interprets visual information

CAUSES OF VISUAL IMPAIRMENT IN CHILDREN

Eye problems in children causing visual

impairment

Anatomy of the eye

Congenital glaucoma

• Rare (1:10000), 65% males• Diagnosed shortly after birth or during 1st year of life• Improper development of the eye drainage channel• Leads high pressure in the eye• Causing damage to optic nerve and results in vision

loss• Symptoms:• Tearing • Photophobia (glaring)• Excessive squeezing of the eye• Buphthalmos (ox eye)

Leucocoria

• White eye reflex• Differential diagnosis• Retinoblastoma • Congenital cataract• Retinopathy of Prematurity• Coat’s disease• Persistent Hyperplastic Primary Vitreous

(PHPV)

1.Leucocoria: Retinoblastoma

Most common intraocular malignancy of childhood Rare (1 in 14000-20000) 3% of all childhood cancers Bilateral in 30-35% Age at diagnosis : 18 months (90% less than 3

years old) May be inherited

1.Leucocoria: Retinoblastoma

• Present with:• Leucocoria (white reflex)• Squint • Poor vision• Eye redness, pain• Proptosis : forward bulging of the eye• Systemic metastases• Incidental ocular exam

Retinoblastoma

• Sight threatening• Life threatening

• Treatment option• Radiotherapy• Chemotherapy• Surgical removal of the eye• Genetic counselling

2. Leucocoria: Cataract

Definition of cataract : Opacity involving the lens

Leucocoria: Cataract

Leading cause of blindness Interferes with normal

visual develoment Inherited –1/3 Associated with other

diseases – 1/3 Idiopathic – 1/3

Nuclear cataract

Lamellar cataract

Cortical cataract

CONGENITAL CATARACT

SECONDARY

Ocular - Anterior subcapsular – Atopic dermatitis

Systemic – oil droplet cataract – Galactossaemia

Vossius ring in traumatic cataract

Presentations of childhood cataract

Lack of visual interest Strabismus/squint Nystagmus : abnormal movement of the eye Developmental delay Associated with systemic/ ocular

abnormalities

Action

Prompt detection & dedicated screening Referral to Ophthalmologist (urgent) Why?

Monocular/ binocular cataract in infants results in significant visual deprivation

Early visual rehabilitation can prevent amblyopia (lazy eye)

• Eye disease that affects prematurely born babies

• Caused by disorganized growth of retinal blood vessels

• May be mild and resolves spontaneously• Severe cases can lead to scarring and retinal

detachment.

3. Leucocoria: Retinopathy of prematurity

Leucocoria: Retinopathy of prematurity

• Risk factor for ROP• Pre-term babies – screening• Low birth weight• Exposure to oxygen

• Screening of premature babies has to continue till school-going age• Risk of myopia, even with no ROP

Leucocoria: Retinopathy of prematurity

Strabismus/squint

• Definition: Deviation of the eyes so that their visual axes are no longer parallel

Causes of squint

• Muscle imbalance• Refractive errors• Ocular abnormalities – cataract, macular

scar, optic disc pathology• Special syndromes – Duanes, Brown• Associated disease – hydrocephalus,

cerebral palsy, meningitis

Other presenting features

• Symptoms• None• Noted by parents• Poor vision• Funny eye movements

• Signs • Poor vision• Abnormal head posture

Management for squint

• Refer to ophthalmologist (urgent)• Treatment of refractive errors• Treatment of amblyopia (lazy eye)• Ocular exercise• Surgery – mucsle imbalance

• Why? • Amblyopia (Lazy eye)• Loss of binocular single vision• Cosmetic blemish

REFRACTIVE ERROR

• Physiological condition whereby the refracting system of the eye does not focus objects on the retina

• A corrective lens has to be placed in front of the eye to enable a sharp image to be seen.

• Myopia• Hyperopia• Astigmatism

Refractive errors

Refractive errors

• Various presentations:• Squeezing eyes• Squint• Headache – ocular/ frontal/ diffuse• Tearing• Complains of tired eyes• Child is slow at school• Has problems with attentiveness• Strong family history of myopia or other refractive

error

• Importance: Untreated or undertreated will cause AMBLYOPIA

• Visual acuity screening in schools• Performed in Standard 1• Referral to

Ophthalmologist/Optometrist

Refractive errors

Amblyopia

• ‘Lazy eye’

• Definition: • Unilateral/ bilateral decrease of best corrected

visual acuity

• Is potentially reversible during the critical period (before 7-9 years old)

Critical period:Why is visual development

important?

• Sensory function continues to develop after birth• Requires proper visual stimulation• Normal vision – receptive cells, clear media and

normal retina• Normal alignment • Normal brain development

How does amblyopia develop?

• Brain receives stimuli from both eyes

• Child’s maturing brain will select the better image and ignore the blurry image• Vision not properly

developed in the bad eye (AMBLYOPE)

Causes of amblyopia

• Ammetropia (bilateral high refractive error)

• Anisometropia (large/ asymmetrical refractive error difference between eyes)

• Strabismic (squint)• Occlusional / form deprivation (media

problem)

Treatment

• Can be treated or reversed if detected earlier (critical period)

• Treat underlying condition – cataract, squint• Prescribe spectacles correction – refractive error• Force to use the amblyopic eye• Patching the good eye• Putting atropine eye drops to blur image in the

good eye

Visual pathway

• As a result of the damage to the brain.• Cerebral palsy• Seizure disorder• Hydrocephalus, Microcephaly

• Infants and children with cortical vision impairment• Delayed in reaching developmental milestones • Sensory motor & activities and social development.• Intellectual disability

Cortical visual impairments

The process of treatment and education that helps individuals who are visually disable•attain maximum function,• a sense of well being, •a personally satisfying level of independence, •optimum quality of life.

Visual Rehabilitation

• OPTICAL DEVICES• NON OPTICAL DEVICES• HOLISTIC APPROACH• Clinicians – ophthalmologist, peadiatrician,

optometrist• Teachers, Education ministry• Occupational therapist• Counsellors : psychologist, psychiatrist, social

worker• Vocational Rehabilitation centers

Visual Rehabilitation

• OPTICAL DEVICES

• Reduced Visual Acuity• Magnification for near• Magnification for distance

• Central visual field defect• Peripheral visual field defect• Reduced contrast sensitivity• Glare sensitivity

Visual Rehabilitation

HAND HELD MAGNIFIERS

MAGNIFICATION FOR NEAR

STAND MAGNIFIERS

SPECTACLE-MOUNTED MAGNIFIER

CLOSE-CIRCUIT TELEVISION SYSTEM

TELESCOPE

MAGNIFICATION FOR FAR

TREATMENT OF CENTRAL VISUAL FIELD LOSS

MODIFIED TEXT

• Training for eccentric viewing- avoid fixating using the fovea

• Using large print material

• Using prism relocation

TREATMENT OF PERIPHERAL VISUAL FIELD LOSS

MIRROR PRISMS

• Acts like a side mirror of a car• Able to view objects at the non-seeing area

of the eye when glancing into the mirror or prism

TREATMENT FOR REDUCED CONTRAST SENSITIVITY AND GLARE

TINTED LENSES

COLOUR CONTRAST

TYPOSCOPE : reduce reflected glare from printed pages

• NON-OPTICAL METHODS • Move CLOSER: use an angled reading desk• Use COLOUR to show objects more clearly• Use CONTRAST: eat white rice off a coloured plate• Pay attention to LIGHTING: sit near a window in

class• Make objects LARGER: write with larger letters• Use a LINE-GUIDE such as a ruler when reading

and writing.

Visual Rehabilitation

• Prognosis for success depends on:• Ocular condition• Vision loss – nature & extent• Patient – physical & mental abilities,

attitude, expectation, motivation• Clinician – attitude & motivation

Visual rehabilitation

THANK YOU