1. PAEDIATRIC
REFRACTION
Gaurish Shrestha, M.Optom, FIACLE
Program Co-ordinator
Bachelor of Optometry program
Institute of Medicine

2. Introduction
 To determine the refractive status of infants
and preverbal children, an objective refraction
is usually used
 A great expertise is necessary in determining
refractive state in terms of judgement of
 Alteration in fixation
 Brightness, thickness and movement of light
 process of emmetropization
 Relationship b/w vision, refraction, state of BSV,
and age of a child

3. Emmetropization
 A process operating to produce a greater
frequency of emmetropia that would be
expected on the basis of chance is known as
emmetropization.

4. Estimation
 ½ of variance in refractive error – due to axial
length
 ¼ of variance – due to corneal curvature
 ½o of variance – due to anterior chamber
 1/5 of variance – due to measurement errors &
variation in lens & refractive index.

5. What is required in Paediatric
refraction?
 This technique must be appropriate for non-
verbals un-cooperatives, non-communicatives in
a child’s part
 This technique must provide important
information in refractive state of eye repeatably
and reliably in instrumental part
 This technique must be understandable, easily
assessable and accessible
 Practitioner must be competent enough to
deliver a perfect judgement

6. What is the greatest challenge to
pediatric refraction?
A great ability of a child to maintain a wide
range of accommodation
Un-cooperation
Greater range of refraction
Difficulty in quantifying visual status
Risk of visual deprivation
Difficulty in making a child understand wear
glasses

7. What are the instruments we
have?
 Keratmeter- preferably hand held
 Retinoscope– A great weapon
 Autorefractor (Need to be portable)

8. Gauri S. Shrestha,M.Optom, FIACLE
Keratometers: uses
 CL fitting and verification
 Monitoring corneal shape
 Calculate the power of intraocular Lens
 Helpful to determine ocular refraction

9. Keratometer-What is its use?
 Estimate corneal refractive
astigmatism
 Regular/ irregular
 Distortion in corneal light reflex
 Find out abnormal corneal conditions
that cause significant refractive error
 Predict success of amblyopia therapy

10. Near retinoscopy (Mohindra
retinoscopy)
 Near retinoscopy is used with infants and
preverbal children from birth to about 3 years
of age.
 Accurate evaluation of refractive error requires
accommodation be stable
 This is usually achieved by one of the three
methods:
 By having the patient fixate at the distance
 By using cycloplegic agent
 By using a target that doesn’t present an effective
accommodative stimulus

11. Principle of near retinoscopy
 The retinoscope is viewed in a dark
surround, the filament is not an
effective accommodative stimulus
 accommodation remains stable
during this technique

12. Actually what happens?
 Most patients exhibits anomalous myopia
during near retinoscopy
 This excessive refractive power reflects a shift
of accommodation towards the patients
intermediate resting focus under reduced
stimulation
 To compensate for this effect, a tonus factor is
applied to the gross refraction obtained with
near retinoscopy
 Tonus factor is +0.75

13. Compensations
 In addition, the working distance
allowance must be taken into
consideration.
 If the working distance is 50cm, the
WD adjustment is -2.00.
the total adjustment factor used is a
combination of the working distance
allowance and the tonus factor (-2.00D +
0.75D = -1.25)

14. Indication for near retinoscopy
Frequent follow up visits are necessary
A child is anxious about the instillation of
the drops
A child is at risk for an adverse effect to
cycloplegic drops (low weight,
neurologically impaired)
A child has previously had an adverse
reaction to cycloplegic drugs

15. Procedure
 All the room light are extinguished and the
child is encouraged to fixate the
retinoscope light by calling their name and
talking reassuringly
 Babies will instinctively fixate the light
 Retinoscopy is performed monocularly at
the working distance of 50cm

16. The potential sources of error
 Too much room illumination. If the
room is not dark the retinoscope
becomes an effective accommodative
target and accommodation becomes
active
 Performing the procedure at an
incorrect working distance
 A very active child who will not
maintain fixation on the retinoscope

17. Caution
 high refractive errors, poor fixation,
poor cooperation, variable pupil,

18.  Cycloplegia
 It is the paralysis
of the ciliary
muscle of the eye,
resulting in the
loss of visual
accommodation
Cycloplegic refraction

19. Gauri S Shrestha, M.Optom, FIACLE
Principle of cycloplegic refraction
 Determination of total
refractive error during
temporary paralysis of
cilliary muscles as an
instillation of
cycloplegic drugs which
otherwise doesn’t
manifest on subjective
non-cycloplegic
refraction
Total Hyperopia
Latent
hyperopia
Manifest
hyperopia
facultative
hyperopia
Absolute
hyperopia

20. Gauri S Shrestha, M.Optom, FIACLE
Indication for cycloplegic refraction
 Accommodative esotropia
 All children younger than 3 yrs
 Suspected latent hyperopia
 Suspected pseudomyopia
 Uncooperative/noncommunicative patients
 Variable and inconsistent end point of
refraction

21. Gauri S Shrestha, M.Optom, FIACLE
Indication for cycloplegic refraction
 Visual acuity not corrected to a predicted level
 Strabismic children
 Amblyopic children
 Suspected malingering and hysterical patients

22. Gauri S Shrestha, M.Optom,
FIACLE
Selection and use of specific
cycloplegic agents
 Variable degree of pupil dilatation and cycloplegia
 Instill cycloplegic alone or with mydriatrics
Agent [C%] Dosage Max
cyclople
Duration
of effect
Residual
accom
Atropine
sulfate
1, 2 1D TID
3 days
3-6 hrs 10-18
days
Ngble
Sco-mine
HBR
0.25% 1D TID 60 mins 5-7 days ngble
Cyclo-
late HCL
0.5, 1, 2 1D TID 30-45
mins
24 hrs minimal
Tro-mide
HCL
0.5, 1 1D TID 20-30
mins
4-8 hrs moderate

23. Important notes
 Children with disorders/ Down’s
syndrome, cerebral palsy, trisomy 13
and 18, and other central nervous
system disorders may have an
increased reaction to cycloplegics
 Low weight infants may need a
modification of dosage

24. Static retinoscopy
 Distance fixation retinoscopy can be
used for children from about 2 years
upwards, depending on the child and
what target is used to gain the child’s
attention

25. Streak motion
 Hyperopic patients
Light focuses behind the retina
Streak movement in same
direction as the retinoscope .
i.e., displays with motion
Add plus lenses to bring the
focusing point up to the retina

26.  Myopic patients
Light focuses at the point
before the retina
Streak movement in opposite
direction as the retinoscope i.e.,
against movement
Add minus lenses to move the
focal point back onto the retina.

27.  Emmetropic patients
No motion of the reflex
observed in the pupil
Also known as neutral
motion or complete
flashing

28. Gauri S Shrestha, M.Optom, FIACLE
What does our practice say?
 Advise atropine cycloplegic refraction invariably in
the children younger than 2 years
 Advise atropine cycloplegic refraction in esotropic
children (accommodative type) up to 4 years
 After 4 years, advise cyclopentolate cycloplegic
refraction up 25-30 years
 Above 30 years, check amplitude and lag of
accommodation, then advise cycloplegic refraction

29. Gauri S Shrestha, M.Optom, FIACLE
Spectacle prescribing
 Prescribing spectacle from cycloplegic
finding is an art rather precise science
 How to prescribe spectacle?
Concept of emmetropization is necessary
Esotropic children younger than 4 years, full
refractive correction is prescribed
With older children, amount of plus can be
reduced till fusion is maintained