May 21-22, 2016

First Basic Course in Clinical Diagnosis & Instrumentation Sentro Oftalmologico Jose Rizal

AMBLYOGENIC REFRACTIVE ERRORS (PRESCHOOL)

  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 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

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

PRESBYOPIA & ACCOMMODATION

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

SA cycloplegia § Tropic 0.5% (1%) q 15

min x 3, after 30 min § Tropic 0.5% -

phenylephrine (San-myd) q3-5 min x 2-3 doses, refract after 30 min

§ AAO: Tropic 0.5% q 5 min x 2, after 30 min

•  Recovery in 2-6h •  Considered inadequate

for most children’s cycloplegia

CYCLOPLEGIA

Bin Aziz, Cycloplegic Agents and Refraction. http://www.slideshare.net/

schizophrenicSabbir/cycloplegic-agents-cyclorefraction

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 Recovery in 24-48h

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)

ERRORS OF INADEQUATE CYCLOPLEGIA •  Less hyperopia •  More myopia •  Higher with-the-rule astigmatism

•  Same errors as computer autorefraction!

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

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

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.

SOME COMMON DIFFERENCES BETWEEN ADULTS AND CHILDREN

CHILDREN < 5 yrs •  Tolerates anisometropia;

give full regardless of age, strabismus, amblyopia

•  < 12y: non wearing or wearing wrong prescription will affect eye health

§  Amblyopia, deviation, loss binocularity

ADULTS •  Tolerates anisometropia

poorly •  Non wearing or wearing

wrong prescription have only minor temporary consequences

§  Asthenopia, red eye, dry eye

SOME COMMON DIFFERENCES BETWEEN ADULTS AND CHILDREN

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)

SOME COMMON DIFFERENCES BETWEEN ADULTS AND CHILDREN

AMBLYOGENIC REFRACTIVE ERRORS (PRESCHOOL)

  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 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

HYPEROPIA >3.5D •  Prescribe plus that gives best VA •  Usually lower than actual cycloplegic refraction •  May not reach 20/20 right away •  Manifest refraction should be considered

ORTHOTROPIA & HYPEROPIA �  High hyperopia >+3.5D Cycloplegic ◦  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

ORTHOTROPIA & HYPEROPIA

Hyperopia: Moderate > +2.50 to +3.50D Cycloplegic § Monitor closely: potential for amblyopia & 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 & HYPEROPIA

�  Hyperopia: Low up to +2.50D 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

MYOPIA >3.0 •  Start with cycloplegic refraction •  Reevaluate with manifest refraction •  Give lowest minus that will yield VA of at least 20/40

ORTHOTROPIA & MYOPIA 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)

MYOPIA </=3.0 •  Start with cycloplegic refraction •  Reevaluate with manifest refraction •  Give lowest minus that will yield VA of at least 20/40 •  Consider child’s visual needs, may not need to

prescribe right away

ORTHOTROPIA & 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

ORTHOTROPIA & 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.

ORTHOTROPIA & ASTIGMATISM 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

ORTHOTROPIA & ASTIGMATISM

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

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

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

WHAT TO DO ON FOLLOW-UP: ACCOMMODATIVE ET

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

0-8PD ET Monofixation syndrome

ACCOMMODATIVE ET: TREATMENT GOAL

Single vision lens § Cycloplegic refraction § Maximum tolerated plus § Push plus

ACCOMMODATIVE ET: NONSURGICAL MANAGEMENT

ACCOMMODATIVE ET: BIFOCALS

•  If and only if distance fusion present (<10PD) •  Reached maximum tolerated plus •  Executive or D segment bisecting pupil

ACCOMMODATIVE ET: PEARLS •  Refraction not always hyperopia •  Give full cycloplegic refractions whenever possible •  Push maximum tolerated plus •  Bifocals if and only if there is fusion at distance •  Goal: minimum bifocals to control near deviation;

eventually get patient out of bifocals

ACCOMMODATIVE ET: PEARLS •  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

X(T) AND REFRACTIVE ERROR

•  Any sensory destabilizing factor affects control, including small EOR

•  Improvement in VA usually helps control deviation

X(T) AND REFRACTIVE ERROR

•  Hyperopia: • If fully corrected, relaxes accommodative-

convergence, control worse • Give minimum plus with best VA, usually better for

control of deviation • Over minus lenses / Withholding hyperopia / giving

less plus has a role in management

X(T) AND REFRACTIVE ERROR Hyperope*: If not for surgery § <5y: 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 ~ >+3.50 on cycloplegic refraction

X(T) AND REFRACTIVE ERROR Myope § Give full cycloplegic refraction (lowest minus) § Consider over minus if not for surgery § Or, give minus lens that will give best VA Astigmat § Give the full cylinder from 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?

�  Significant cylinder &/or significant myopia

�  Dry manifest refraction highest and exceeds cycloplegic refraction

�  May need stronger cycloplegia to determine true target refraction

�  Pharmacologic cycloplegia

CILIARY MUSCLE SPASM

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

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.

5.   Bin Aziz, MA. Cycloplegic agents and cyclorefraction. http://www.slideshare.net/schizophrenicSabbir/cycloplegic-agents-cyclorefraction. Accessed March 15, 2016.

6.   Apt L, Gaffney M. Cycloplegic Refraction. http://80.36.73.149/almacen/medicina/oftalmologia/enciclopedias/duane/pages/v1/v1c041.html. Accessed March 15, 2016.