prescribing eyeglasses for children revisited 2015 v2

Prescribing Eyeglasses for Children Revisited

Alvina Pauline D. Santiago, MD Pediatric Ophthalmology & Strabismus

November 2015

Prescribing Eyeglasses: Theoretical Framework

No universal guidelines

� Controversies vs. trends in prescribing eyeglasses in children �  de Respinis, Wagner, Caputo et al �  AAO 94, 95; AAPOS 94, 95, … �  Continuing education

� Defining threshold refractive error � Defining a child’s visual needs � Defining adequate cycloplegia

Factors affecting decision to prescribe

� Age and tolerable glasses �  Visual Needs � Cycloplegic refraction � Alignment � Development of amblyopia � Developmental milestones � Associated abnormalities or delays �  Parents – attitude, finances

Cycloplegia

�  SA cycloplegia ◦ Tropic 0.5% (1%) q 15 min x 3, after 30 min ◦ Tropic 0.5% - phenylephrine (San-myd) q 3-5

min x 2-3 ◦ AAO: Tropic 0.5% q 5 min x 2, after 30 min

Cycloplegia

�  Intermediate cycloplegia ◦ Cyclopentolate 1% (2%) q 5 min x 2, after 40

min ◦ Tropic-phe-cyclopent (0.5/2.5/0.5%: Caputo

drops) q 5min x 2, after 30 min

◦ AAO: C1% q 5min x 2, after 30 min

Cycloplegia

� Long acting cycloplegia ◦ Atropine 1% gold standard �  Forewarn patients about atropine flush & skin

warmth, and product insert problems. �  Dilute if necessary �  TID x 3 days and morning of visit �  BID x 2 days may be adequate (Rosenbaum,

personal communication) �  Caution in infants, albinos, trisomy 21 (Down)

Cycloplegia

� Long acting cycloplegia ◦ Atropine 1% gold standard ◦  Product inserts problem: wrong statements �  1% should not be used in children �  Should not be used in patients with Down

Syndrome

Errors of inadequate cycloplegia � Less hyperopia � More myopia � Higher with-the-rule astigmatism

�  Same errors as computer autorefraction!

Key Concepts

�  “Normal refraction” �  Significant refractive error � Amblyogenic errors of refraction � Process of Emmetropization � Accommodation & Convergence ◦ Need for cycloplegia

� Eye alignment and refraction � Children are not “little adults”

Refraction of the Eye

� Corneal Power � Lens Power � Anterior chamber depth � Axial diameter of the globe

�  Jensen 1997

Emmetropization

� Children with EOR at birth usually become more emmetropic with age

� Argument against giving glasses early � Disturbance in emmetropization causes

persistent myopia and hyperopia �  Jensen 1997

Emmetropization

� “The developmental process which coordinates growth of the refractive components of the eye to create a non-Gaussian distribution of EORs around emmetropia”

� Dependent of visual experience of the

infantile eye. �  Lambert 1997

Emmetropization

� Animal studies: ◦  Inducing hyperopic or myopic EOR with

external lenses = axial elongation �  If myopic error induced: eye elongates less �  If hyperopic error induced: eye elongates

excessively �  (Troilo & Wallman 1991, Hung et al 1996)

�  Lambert 1997

Emmetropization

� Correcting EORs in infants may have similar effect ◦ Higher percentage of children remain hyperopic

if corrected with spectacles during infancy �  (Ingram et al 1991)

�  In Lambert 1997

Emmetropization

� Correcting EORs in infants may have similar effect ◦  Longitudinal study: cohort of children with family

history of accommodative esotropia �  If high hyperopia shifted to emmetropia during first 2

years of life, none developed ET �  If high hyperopia retained, developed ET �  WHY? Not clear

�  Aurell and Norrsell (1990)


Emmetropization

� Visual deprivation interferes with emmetropization ◦ Macaque monkeys: lid closure or corneal

opacification in infancy led to axial myopia (only in posterior segment)

�  (Raviola and Wiesel 1995)

◦ Chicks: Visual deprivation in nasal or temporal half=asymmetric growth of the posterior segment

�  (Wallman et al 1987) �  In Lambert 1997

Emmetropization

� Visual deprivation interferes with emmetropization ◦  Light dependent phenomenon: axial myopia with

deprivation does not develop if chick is reared in the dark

�  (Raviola & Wiesel 1978; Guyton et al, 1989) �  In Lambert 1997

Factors Affecting Emmetropization

� Axial myopia develops in children with ◦  congenital cataract

�  (Rabin et al 1981, Johnson et al 1982, von Noorden & Lewis 1987, Rasooly & BenEzra 1988)

◦ Corneal opacities �  (Curtin 1985; Gee & Tabbara 1988, Twomey et al 1990)

◦  Ptosis �  (Hoyt et al 1981; von Noorden & Lewis 1987)



� Axial shortening produced by removing crystalline lens during infancy

�  (Wilson et al 1987, Tigges et al 1990, Lambert et al 1996, Kugelberg et al 1996)

�  suggest factors produced by crystalline lens stimulate ocular growth.



�  Accommodation may also influence the refractive development of infantile eyes

�  Role of chronic atropinization during childhood to

reduce progression of myopia? �  (Kelly et al 1975; Brodstein et al 1984)

�  In animals, accommodation independent of chronic atropinization or ablation of E-W nucleus

�  (Troilo 1992) �  In Lambert 1997

Atropine for myopia

� Atropine 0.01% ◦ Over 5 years, more effective in controlling

myopia progression ◦ Minimal side effects ◦ Negligible effects on pupil size, accommodation,

no effect on near acuity ◦ Modulated and sustained effect, no rebound

1.  Chia A, Chua WH, Cheung YB etal. Atropine for the treatment of childhood myopia: safety and efficacy of 0.5%, 0.1%, 0.01% (Atropine for Myopia 2) Ophthalmology 2012; 119.347-54.

2.  Chia A, Chua WH, Wen L, et al. Atropine for the treatment of childhood myopia: changes after stopping atropine 0.01%, 0.1%, and 0.05%. Am J Ophthalmol 2014; 157: 451-7.

3.  Chia A, Lu QS, Tan D. 5-year clinical trial on atropine for the treatment of myopia 1: myopia control with atropine 0.01% Eyedrops. Ophthalmology 2015; epub ahead of print.

Myopia

� Genetics? � Disturbance in emmetropization � Altered visual input during post natal

development ◦ Congenital cataracts, Lid hemangiomas,

Corneal scarring, Lid ptosis

Hyperopia

� Genetics? �  Foveal pathologies before age 3 years ◦ Maculopathies, rod monochromatism ◦ Disruption of central vision leads to failure of

emmetropization

�  Failure of emmetropization leads to development of ET, amblyopia and XT

Refractive Changes During Childhood: Spheres

� Birth: Maternal Hospital ◦ Hyperopic but wider fluctuation / SD ◦ Cook & Glasscock 1951 Atropine cycloplegia �  +2.0 D mean, (SD 2.75). Range -7 to +11

�  Increasing age, Decreasing hyperopia, less SD

� Emmetropization around school age

Amblyogenic refractive errors EOR Freedom &

Preston 1992 Cibis-Tongue & Grin

Atkinson et al

Hyperopia > +3.50D >+4.00D >+3.50D

Myopia >-1.00D >-2.00D >-2.00D

Aniso-metropia

>1.50D >1.00D >1.00D

Cylinder >1.50D >1.00D >1.50D

Amblyogenic Refractive Errors

� Myopia > -1.00 D � Hyperopia ◦  0-1 y: >+4.00 D ◦  1-2 y: >+3.50 D ◦  2-6 y: >+2.00 D

� Astigmatism >1.50 D � Anisometropia > 1.50 D

�  Freedman, Preston, Ophthalmology 1992

Amblyogenic Refractive Errors

Anisometropia (sph or cyl) > 1.5D Hyperopia >3.5 in any meridian Myopia >3.0 in any meridian Astigmatism >1.5D at 90/180 deg Astigmatism >1.0D >10 deg any meridian

Amblyogenic Factors detected by Screening

� Astigmatism ◦ >1.5D at 90, 180 - >1.0 D at oblique axis (>10deg of 90, 180)

� Ptosis </= 1 mm MRD � VA per age appropriate standards

� Donahue etal & AAPOS Vision Screening Committee, J AAPOS 2003

Some common differences between adults and children

CHILDREN < 5 yrs �  Give refraction on axis

as refracted �  Full hyperopic

cycloplegic refraction tolerated well if less than age 5 y

�  Subjective manifest refraction less important

ADULTS �  Give cyl closer to 90 or

180 degrees �  Maximum tolerated plus

even in refractive accommodative esotropia

�  Subjective manifest refraction important.


CHILDREN < 5 yrs �  Tolerates anisometropia

�  < 12y: non wearing or wearing wrong prescription will affect eye health ◦  Amblyopia ◦  Deviation ◦  Loss of binocularity

ADULTS �  Tolerates anisometropia

poorly �  Non wearing or wearing

wrong prescription have only minor temporary consequences ◦  Asthenopia ◦  Eye redness ◦  Dryness


CHILDREN < 5 yrs �  Tolerates aneisokonia better

but also considered an impediment to fusion and has amblyopia potential

�  Anisometropic Rx, Aneisokonic spectacle Rx has a role especially in patients requiring occlusion

ADULTS �  Tolerates aneisokonia poorly

�  Will not wear Rx that has a large difference in refraction between the 2 eyes (threshold? Different from patient to patient)

Accommodation & Convergence �  Stimulus for binocular adjustment at near

1.  Change in vergence of light reaching fovea 2.  Temporal disparity of 2 images relative to 2 foveas

�  Normal conditions: a unit change in accommodation (D) is accompanied by a unit change in convergence (meter angle)

�  Change in convergence produced by change in

accommodation = accommodative convergence �  Meter angle: Angle formed by each visual axis with a line

perpendicular to interpupillary line �  ( Moses in Adler’s Physiology of the Eye 1987)

Accommodation & Convergence

�  Change in accommodation can also be induced by convergence alone ◦  24 y: physiologic maximum ◦  Older persons: rate of increase in

accommodation with increasing convergence is reduced

�  Unconditioned reflex �  Synkinetic reflex with pupillary miosis

�  ( Moses in Adler’s Physiology of the Eye 1987)

Presbyopia & Accommodation

�  Reduced amplitudes of accommodation ◦  8 yrs old: up to 14D ◦  20 yrs old: up to 11D ◦  30 yrs: up to 9D ◦  40 yrs : up to 4 D ◦  50 yrs : less than 2 D

�  Continues unabated until age 60 y

http://iovs.arvojournals.org/data/Journals/IOVS/932949/z7g0060889470008.jpeg

Common Clinical Situations

Strabismic Patient: Esotropia, Exotropia Pediatric Aphakia Orthotropic Patient

Esotropia and Refractive Error

�  FULL cycloplegic refraction ◦ Myope: give full cycloplegic refraction ◦ Hyperope: More common, > +2.00D �  < 5 y: give full cycloplegic refraction �  >5 y: maximum tolerated plus, push plus

◦ Astigmat: �  Give the full cylinder from cycloplegic refraction

Esotropia and Refractive Error

� When to give bifocals: ◦ High AC/A ◦  Fusion at distance present (<10PD) ◦  Full cycloplegic refraction / maximum

tolerated plus pushed ◦ Repeat full cycloplegic refraction first ◦ Careful with “V” pattern confused with

high AC/A

ET High AC/A and Adds �  Either give full +3.00D adds then taper, or give

minimum adds +1.00D then go higher to where ET’ controlled

�  Objective: minimum plus to control ET’ �  Monitor X(T) at near, excess adds �  Must bisect pupil �  Executive, flat top, D-segment �  Kryptok or progressive not helpful �  ? Progressive or no line in teenagers as you are

tapering bifocals

What to do on follow-up: Accommodative ET

�  Amblyopia �  Refraction �  Fusion at distance �  Residual near deviation �  Repeat refraction �  Amblyopia management �  Remeasure with glasses

always

Accommodative ET: Follow-up

� Remeasure deviation with glasses ALWAYS both at distance and near

�  If ET at distance ◦ Consider undercorrected hyperopia first

before surgery

�  If no ET at distance, ET’ at near only ◦ Recheck refraction, repeat cycloplegia,

increase plus if necessary ◦ Consider high AC/A requiring bifocals

Accommodative ET: Follow-up

�  If XT at distance ◦ Reduce plus correction

�  If XT at distance, ET at near ◦  -reduce distance plus ◦  Minimum Bifocals that will control near

deviation

�  If ortho at distance but XT at near ◦ Reduce adds

Accommodative ET: Treatment goal

�  0-8PD ET �  Monofixation

syndrome

Accommodative ET: Nonsurgical Management

�  Single vision lens ◦  Cycloplegic refraction ◦  Maximum tolerated plus ◦  Push plus

Accommodative ET: Bifocals

�  If and only if distance fusion present (<10PD)

� Reached maximum tolerated plus � Executive or D segment bisecting pupil

Accommodative ET: Miotics �  Infant with no refractive error � Not tolerating bifocals � Echothiopate, isofluorophate � Drug interaction with succinyl choline �  Innervationally produced cholineesterase

in ciliary body reduced, thereby decreasing required accommodative effort

� Retinal detachment

Accommodative ET: Miotics

� Variable results �  Side effects: ◦  accommodative spasm, ◦  pupil constriction, ◦  iris cyst, ◦  lens changes, ◦ Retinal detachment

Accommodative ET: Pearls

� Refraction not always hyperopia � Give full cycloplegic refractions whenever

possible � Push maximum tolerated plus � Bifocals iff there is fusion at distance � Goal: minimum bifocals to control near

deviation; eventually get patient out of bifocals


� Always check/repeat refraction for latent hyperopia

� Role of atropine in uncovering hyperopia � Measure deviation wearing the correction � Perform simultaneous prism cover test

first before alternate prism cover test � Latent esotropia not for surgery


�  Fadenoperation (or posterior fixation) for near deviation an option

� May opt to reduce plus after surgery, when deviation is controlled

� WOF exotropia, need to reduce plus

X(T) and Refractive Error

�  FULL vs. SA cycloplegic refraction � Any sensory destabilizing factor affects

control, including small EOR � Hyperopia: If fully corrected, relaxes

accommodative-convergence, control worse

� Over minus lenses / Withholding hyperopia / giving less plus has a role in management

X(T) and Refractive Error

� Myope ◦ Give full cycloplegic refraction (lowest minus) ◦ Consider over minus

� Astigmat ◦ Give the full cylinder from cycloplegic

refraction

X(T) and Refractive Error �  Hyperope*: If not for surgery ◦  Cut plus by 1-1.5D ◦  Minimum plus to control X(T) and give clear vision ◦  Older children, consider manifest refraction ◦  Excess plus can worsen X(T)

�  Hyperope*: For surgery ◦  Give the full cycloplegic refraction or maximum

tolerated plus prescription to uncover all latent exodeviation. ◦  Target angle for surgery

*Significant hyperopia ~ >+3.00 on cycloplegic refraction

Anisometropia & Refractive Error

� Monocular XT ◦ Anisometropic amblyopia ◦ Cut plus by 1-1.5D ◦  If >5 y, may need to manage like a little adult,

decrease anisometropia in glasses ◦ Consider contact lenses to optimize vision ◦  Prescribe glasses with patching ◦ Role of laser refractive surgery?

Anisometropia & Refractive Error

�  Monocular ET ◦  Anisometropic amblyopia ◦  Usually with refractive accommodative component ◦  Full cycloplegic refraction or maximum tolerated plus ◦  If >5 y, may need to manage like a little adult:

decrease anisometropia in glasses ◦  Prescribe glasses with patching ◦  Consider strongly: contact lenses ◦  Role of laser refractive surgery?

Ciliary Muscle Spasm

�  Significant cylinder &/or significant myopia � Dry manifest refraction highest and exceeds

cycloplegic refraction � May need stronger cycloplegia to determine

true target refraction � Role for pharmacologic cycloplegia ◦  Short acting: tropicamide, Sanmyd-P ◦  Long acting: atropine 1%

Ciliary Muscle Spasm

� Give lowest minus, lowest cylinder � Resist urge to give in to subjective

refraction ◦  usually higher minus ◦ more with-the-rule astigmatism (minus cyl x

180)

� Compromise needed for school age: ◦  at least 20/40 (6/12 or 0.5) OU

Theory for Ciliary Muscle Spasm

�  Near work requires both accommodation & convergence

�  Uncorrected myopes: excess convergence required compared to accommodation

�  If accommodation = convergence, ciliary muscle spasm induced: higher myopia (than true refractive state)

�  If convergence given up at the expense of binocularity = XT

�  Jensen 1997 in Taylor’s Pediatric Ophthalmology

Orthotropia & Refractive Error

� Myopia ◦  Low myopia (<-1.0D): �  depends on visual tasks

�  Preschool child, even up to grade 3, OBSERVE �  Intermediate (Gr 4 or higher), give cycloplegic Rx

�  Rare for a child to complain about blurred vision �  Depends on symptoms:

� Anomalous head posture � Cannot see board �  Squinting (pinhole behavior) �  Spasm of accommodation, etc.


� Myopia ◦ Moderate myopia: -1.0 to -3.0D �  Potential for amblyopia �  depends on visual tasks

� Up to age 1, OBSERVE if -1.0 to -1.5D � Above age 6 mos, if >-2.0D, give cycloplegic refraction �  School age, give cycloplegic Rx

�  Depends on symptoms: AHP, squinting, spasm of accommodation, etc.

�  Give cycloplegic refraction


� Myopia ◦ High myopia: > -3.0D �  Amblyogenic �  Double check with stronger cycloplegia, usually

atropine �  More than age 6 mos: give cycloplegic refraction �  Check refraction q 3 months �  Regardless of symptoms (with or without

symptoms)


� Hyperopia: Low up to +3.0D cycloplegic ◦ Asymptomatic OBSERVE only for ET and

amblyopia ◦  If cooperative, get dry manifest and subjective ◦  If cooperative with symptoms, give lowest

plus with good enough VA (20/40) so as not to interfere with emmetropization ◦  If symptomatic uncooperative, �  Consider observe �  Consider giving plus but cut by +1.0 to +1.50D


� Hyperopia: Moderate > +3.0 to +4.0D ◦  Potential for amblyopia! And refractive

accommodative esotropia ◦ Cut by +1.0 to +1.5D ◦  some start by giving half ◦  If cooperative, get dry manifest and subjective ◦  If cooperative with symptoms, give lowest plus

with good VA

Orthotropia & Refractive Error �  High hyperopia >+4.0D ◦  Amblyogenic ◦  Asthenopic symptoms common ◦  Risk for developing refractive accommodative ET ◦  Cut plus from cycloplegic refraction by +1.0 to +1.5D

in younger child, ◦  May cut plus even higher in the cooperative child if

good manifest refraction can be obtained; ◦  some start by giving half plus


� Astigmatism ◦ With-the-rule �  Up to -1.50D cyl at 180 tolerated without Rx �  Consider potential for amblyopia and associated

symptoms �  Give full cylinder from cycloplegic refraction ◦ Against-the-rule �  Probably not tolerated as well even if low �  Tend to give cycloplegic refraction earlier


� Astigmatism ◦ Oblique axis (exceeds 10-deg from 90 or 180) �  Threshold lower: >1.0D, give Rx early �  Consider potential for amblyopia and associated

symptoms �  Give full cylinder from cycloplegic refraction on-axis �  If cooperative and reliable with manifest, check if

90/180 degrees preferred

Special Problem: Pediatric Aphakia ◦ Monocular �  Soft “scleral” contact lens �  Emmetropia to slight hyperopia �  Consider other eye: avoid anisometropia �  Need adds eventually �  Pseudoaccommodation

◦  Binocular �  Contact lenses and glasses �  Reading adds

Pediatric Aphakia

� Repeat refraction q 1-3 mos � Bifocals at about age 1 year or later (e.g.

school age) affects ambulation in early stages of motor development

� Executive / flat top / D-segment � Aspheric / high index lenses � Not readily available if > +18.0D

References

1.  Hanne Jensen. Refraction and Refractive Errors.

2.  Lambert S. Postnatal growth of the eye and emmetropization. In Pediatric Ophthalmology, David Taylor ed. Blackwell Science 1997

3.  Adler’s Physiology of the Eye 4.  Clinical Optics. AAO Basic and Clinical

Course 2014-2015, pp. 113-115.

References 1.  Chia A, Chua WH, Cheung YB etal. Atropine for the treatment of childhood myopia: safety

and efficacy of 0.5%, 0.1%, 0.01% (Atropine for Myopia 2) Ophthalmology 2012; 119.347-54.

2.  Chia A, Chua WH, Wen L, et al. Atropine for the treatment of childhood myopia: changes after stopping atropine 0.01%, 0.1%, and 0.05%. Am J Ophthalmol 2014; 157: 451-7.

3.  Chia A, Lu QS, Tan D. 5-year clinical trial on atropine for the treatment of myopia 1: myopia control with atropine 0.01% Eyedrops. Ophthalmology 2015; epub ahead of print.

4.  Donahue SP, Arnold RW, Ruben JB, AAPOS Vision Screening Committee. Preschool vision screening: what should we be detecting and how should we report it? Uniform guidelines reporting results of preschool vision screening studies. J AAPOS 2003; 7: 314-5.

prescribing eyeglasses for children revisited 2015 v2

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