1. Gauri S. Shrestha, M.Optom, FIACLE
Sujata Rizal, B.Optom Final Year
Prativa Devkota, Final year

2. Uncorrected refractive error leads to:
Amblyopia
Delayed visual maturation
Deviation of the eyes

3. 1. Is the refractive error within the normal range for the
child’s age?
2. Will this particular child’s refractive error
emmetropise?
3. Will this level of refractive error disrupt normal visual
development or functional vision?
4. Will prescribing spectacles improve visual function or
functional vision?
5. Will prescribing glasses interfere with the normal
process of emmetropisation?

4.  Knowledge about the normal refractive error of
infants
 Emmetropization process
 The benefits and risks of prescribing spectacles
 Any threat to normal visual development by the
prescription

5.  Most infants are hyperopic by +2.00 D with SD of 2.0
 In Initial 3 months, controversy over refractive status
to be static or decreasing.
 Average is +2.16 D

6.  There is rapid decrease in refractive status from
3 months to 12 months.
 The error decrease to 1. 36 D at 9 months
 What happens after ……12 months?
 This is followed by a period of slower change
until two years for hyperopes and four to five
years for myopes

7.  Few children myopic at birth
 most of those who are either myopic or
 hyperopic will emmetropise.
 The rate of emmetropisation is generally proportional
to the initial error.
◦ those who start off close to emmetropia or with a low
amount of hyperopia show little change
◦ those who have higher ametropia generally show greater
and faster changes

8.  Higher prevalence of astigmatism at birth but
decrease in degree and magnitude
◦ 69% of children have astigmatism greater than 1.00 D at
birth
 90% Swedish children with astigmatism of +1 or more
was reported to decrease.
Astigmatism of 1 or more
(%)
Age
8-30% 1.2 yrs
4-24% 3-4 yrs

9.  Higher astigmatism decrease more rapidly in
initial 3-4 years
 Significant WTR, ATR and oblique astigmatism (
least common) are all more common
 all types of astigmatism decrease, with infants
losing approximately two-thirds of their
astigmatism between nine and 21 months (most
common: 1.5- 2 yrs)

10.  Anisometropia (≥1D) is more common in infants
than adults.
 spherical anisometropia remains more common in
children compared with adults up to four years of
life
 Anisometropia is transient in relatively lower level
of refractive error, for example, 2.50 D or less and
may not lead to amblyopia

11.  Probability of emmetropisation decreases as
hyperopia increases.
 Probability is < than 50 % for three-month-olds,
who had a cycloplegic spherical equivalent
refraction
greater than 5.00 D.

12.  Hyperopic children with ATR astigmatism at six
months maintained their hyperopia
(approximately
2.00 D on average)
 Hyperopic children with WTR astigmatism lost
their
hyperopia (ending up at approximately 0.75 D
hyperopic at age six years)

13.  Main tool to predict emmetropisation is to monitor
the
refraction.
 Those who emmetropise, lose approximately one-
half of their spherical equivalent refractive error in
the first
year and approximately one-third between nine
and 21
months.
 With regards to astigmatism, approximately two-
thirds of the astigmatism is lost between nine and
21 months.

14.  No way to predict with certainty whether a particular child’s
anisometropia is transient or will remain into adulthood.
 Following things should be taken into account:
 monitor a child over a period of four to six months
 consider VA—if amblyopia is already present it requires
treatment
 higher levels of anisometropia (for example, >3.00 D or more
and particularly 5.00 D or more) are less likely to be transient.
 children with low vision are less likely to fully emmetropise .
 Therefore, these children can be prescribed, with the main
consideration being to optimize visual function.

15.  Association between lack of emmetropisation and
the presence of strabismus.
 However, its not clear whether strabismus interferes
with emmetropisation or whether those who do not
emmetropise, and thus maintain their higher
hyperopia, are more likely to develop strabismus

16.  Uncorrected high refractive error (hyperopia,
astigmatism and anisometropia) during the first few
years of life is a risk factor for amblyopia
 There is an increased chance of monocular or
binocular amblyopia in one-year-olds with 3.50 D or
more in one meridian,

17.  Partial correction of hyperopia greater than 3.50 D
at
nine to 11 months resulted in improved VA at four
years of age and may reduce the incidence of
eso
 In children with 5.00 D or more,
◦ 25 to 43% have acuity of 6/12 or worse
◦ 87 per cent have acuity worse than 6/6.
◦ Poor accommodation and stereopsis

18.  In the study by Atkinson and colleagues, there
was
no difference in the reduction of hyperopia
comparing
those who were fitted with a partial prescription
and the controls.

19.  Many authors recommend monitoring the refraction
(hyperopia, myopia or astigmatism) in infants and
toddlers before prescribing.
 Frequently unchanging or increasing refractions
are
associated with amblyopia.

20.  Only demonstrable amblyopia indicate immediate
prescribing
 The other main factor, which will influence one’s
likelihood of prescribing for hyperopia, is the presence
of heterophoria.
 Correction of hyperopia to optimize alignment

21.  Prescribing if the refraction is outside the 95% limits for
a particular age.
 Main aim is to bring the uncorrected portion just within
the normal range, for example, to the 95% limit.
 This would leave a large stimulus for emmetropisation
and therefore potentially encourage a greater amount of
emmetropisation

22.  It seems that the child’s accommodation cannot
overcome the very large uncorrected hyperopia but a
correction that is small enough to bring them just within
the normal range allows them to accommodate for the
remaining hyperopia, resulting in esotropia.
 Thus, when a larger prescription is given, it is imperative to
see the child approximately four to six weeks after the
prescribing appointment

23.  >3.50 D in one or both meridian
 Atkinson’s protocol based on the plus cylinder
format at this was:
◦ sphere : prescribe 1.0 D less than the least meridian
◦ Cylinder: prescribe half of the astigmatism if
>2.50 D

24.  < -5.0 D during the first year, reduce by 2.0 D.
Under correct because emmetropisation occurs in
myopia

26.  In study of Mohindra and Held (1981), refracted 400
children ≤5 yrs using near retinoscopy.
 For children 0 to 4 weeks they found bell shaped
distribution of refractive error ranging from -14 D to
+ 12D gradually narrowing to range of -3 to +4 D at
age of 129 to 256 weeks.
 This demonstrate the process of emmetropization is
evident.

27.  In a study of 1,432 unselected children, Sorsby,
Benjamin, and sheridan (1961) found the mean
ocular refraction under cycloplegia, decreased
from +2.33D at age 3yrs to 0.93 D at age of 14yrs
in boys and from 2.96D at age 3yrs to 0.64D at
age 15yrs for girls.

28.  Prevalence of myopia is found to be steadily
increasing during school years.
 In study Blum, Peters, and Bettman found that
prevalence of myopia increased from about 2 % at
age 6 to 15 % at age 15.

31.  the refraction with higher hyperopia and with
emmetropia remains unchanged
 the refraction with moderate hyperopia still shows
a drift towards emmetropia up to nine or 10 years
of age
 In the school years, myopia should be corrected
for function with full correction

32. When to consider
prescribing
What to prescribe?
Outside the 95% range
of refraction at any age
according to any
currently available
data. This guideline
could be applied to
other refractive errors
also.
Prescribe so as to leave the uncorrected
hyperopia
somewhat above the mean for the age
3 to 6 months if outside
the 95% range (Partial
correction)
In addition to the level of hyperopia
determined by cycloplegic refraction,
factors that would indicate correction are
VA poorer than 6/100 plus non-
cycloplegic (Mohindra) refraction that is

33. When to
consider
prescribing
What to prescribe? Comments, rationale
and references
> 3.50 in one or
more meridian at
age of 1 year
upwards
Give partial
prescription
Atkinson’s protocol :
prescribe 1D less than
least hyperopic
meridian
Based on randomised
clinical trials of Atkinson and
colleagues and natural
history study of Ingram and
colleagues
>2.50 at 4 years
upward
Still give partial
correction of hyperopia
Under correct by 1 to
1.50 D*
Based on studies of visual
function and functional
vision and Mayer and co-
worker’s
> 1. 50 D in the
school years
without symptom
Full or near full
correction may be
given at this age, as
emmetropisation has
Studies on visual function
show that hyperopia ranging
from > 1.00 to > 2.00 D may
impact visual function .

34. When to
consider
prescribing
What to prescribe Comments, rationale and
references
>2.50 D at 15
months of age
upwards
Decrease cylinder by 1.00 D
or give 50%
15 month of period is the most
critical period
> 2. 00 D at 2
years or upward
Give partial cylinder up to 3 to
4 years after which give full
cylinder
Based on finding of better VA in
children whose astigmatism was
corrected at this age and at 2
years approximately 5 to 10%
have astigmatism > 2.00D
> 1.50 D at 4
years upwards
Give full cylinder and in case
of previously uncorrected
high astigmatism, reduced
prescription may be given to
allow child to adapt
Based on studies of Cowen and
Bobier 95th
percentile for
astigmatism was 1.25 in children in
mean age of 4 years
> 1.00 D oblique
astigmatism from
Correct ¾ to the age of 2
and then correct the full
Oblique astigmatism is risk factor
for amblyopia. Mayer and

35. When to consider
prescribing
What to prescribe Comments, rationale
and references
> 3.00D at 1 year upward Prescribe full anisometropia
if amblyopia is already
present, if there is no
amblyopia reduced
anisometropic correction
could be considered
> 3.00 D of
anisometropia is less
likely to be transient
according to report of
Abrahamsson
> 1.00 D but < 3.00 D after 1
year of age
Monitor for 4 to 6 months
and if persist prescribe
myopia and hyperopia
according to age
Based on report of
transient myopia
> 1.00 D of spherical
hyperopic anisometropia,
≥2.00D of spherical myopic
anisometropia, > 1.50 D of
cylindrical anisometropia after
Prescribe myopia and
hyperopia according to age
This level of amblyopia is
found to be amblyogenic
at this age

36. When to consider
prescribing
What to prescribe Comments, rationale,
and refrences
< -2 .00D myopia
from one year
Reduce by 0.50 or 1.00 D
until school age
MEPED study showed that <
-1.2 to -1.7 is the lower end
of 95% range in African
American
4 years to early
school years
In correction of low amount of
myopia improves vision ,
correct it. Give full correction
for high amount of myopia
Congdon and colleagues
found the correction of
<0.75 D improved VA.
School age myopia Prescribe full correction. In
cases of myopia with near
esophoria , larger lag of
accomodation or shorter
habitual reading distance,
PAL may be considered
Guideline for bifocal
correction based on the
correction of Myopia
Evaluation Trial Study for 6
to 11 years old

37.  Overcorrect by 2 to 3.00D because child’s world is
near.
 After 2 to 3 years, distance correction with bifocal
is better option

41.  Prescription of spectacles thus must be done
keeping factor like emmetropization and
amblyogenic factor in mind.

42.  Susan J Leat . To prescribe or not to prescribe?
Guidelines for spectacle prescribing in infants and
children. Clin Exp Optom 2011; 94: 6: 514–527.
 Jane Farbrother. Spectacle prescribing in childhood: a survey
of hospital optometrist. Br. J. Ophthalmol.
 SEAN P. DONAHUE. Prescribing Spectacles in Children: A
Pediatric Ophthalmologist’s Approach. Optometry and Vision
Science, Vol. 84, No. 2, February 2007
 Ashwin Sainani. Special considerations for prescription of
glasses in children. Journal of Clinical Ophthalmology and
Research - Sep-Dec 2013 - Volume 1 - Issue 3