December 30, 2019 | POSTED BY | Articles, Clinical Optometry, Clinical Pearls
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When it comes to having a young child in your exam chair, how prepared do you feel? Do you know what to expect from a 3-year old? 5-year old? 12-year old? If your response is anything other than “completely prepared,” let’s spend a little time going over the big (and the little!) things that will help you hit the key elements of a pediatric exam.

Milestones

First thing’s first: do you know the major developmental milestones of a child? These are important in letting you know what things you can and cannot do, testing-wise, as well as what to expect from the child based on age.

  • Newborn: birth to 1 month
  • Infant: 1-18 mo (Under 6 months of age = congenital)
  • Toddler: 18-36 mo
  • Preschooler: 3-5 yr
  • School-age child: older than 5 yr

Important Milestones Under 12 Months of Age

  • Following an object (with eyes)—1 month
  • Bringing hands together and exploring with hands—2 months
  • Tracking/Reaching for things—3 months
  • Turning eyes together to focus on near objects—4 months
  • Peek-a-boo and making sounds for “P”, “B”, “T”, “D”, “M”—5 months
  • Rolling over independently—7 months
  • Sitting up without support—8 months
  • Creeping and crawling—9 months
  • First eye exam—6 months

     

Exam Elements that are testable around 6 months of age include:

    1. Fixation and following
    2. Preferential looking (Teller Acuity)
    3. Alignment
    4. Accommodation
    5. Stereopsis (basic stereo: Lang, Frisby)
    6. Reaching for objects
  • In addition to poor visual acuity, infants will not have a bright foveal reflex until about 15 months of age.

Additional Milestones in Visual Development

Spatial Vision

  • VA that requires visual processing (via subjective methods) by the infant do not show 20/20 levels until 3-4 years of age.
  • OKN drum: elicits optokinetic nystagmus when rotated slowly. Eye slowly follows direction of rotation, then fast saccade in opposite direction to refocus on a stripe. *Infants have an asymmetric OKN until 3-5 mo of age due to incomplete development of the cortex.
    NORMAL: Temporal→nasal OKN (TONS of movement)
    ABNORMAL: Nasal→temporal OKN (a “negative response” is inconclusive. Attention vs. lack of ability)

Refractive Error

  • Average refractive error for a full-term baby = +2.00 D
  • Astigmatism present in 50% of newborns
  • Average axial length for full-term newborn = 16 mm
  • Premature Infants (born < 37 weeks) typically have:
    -High myopia
    -High astigmatism
    -Anisometropia
    -Often have a normal emmetropization with similar levels of hyperopia and astigmatism by 12 mo.
  • At 10 weeks: mean refractive error = +0.00 to +4.00 D
    • (emmetropization decreases hyperopia, reaching +0.00 to +3.00 by 20 weeks)
  • At 12 months: mean refractive error is +0.50 D – +1.00 D
    • remains stable until teen years
  • Astigmatism
    • At 6 mo: ave = -2.00 D ATR astig
    • At 2 yrs: ave = -0.50 D or less (decreases)

Color Vision

  • Newborns to 3 mo: can only discriminate between red and achromatic stimuli.
  • 3 to 4 mo: ability to discriminate all hues from achromatic stimuli reaches adult levels, but continues to develop
  • 4 to 7 mo: scotopic sensitivity curve in infants reaches adult levels

Accommodation and Convergence

  • Accommodation and convergence become linked after 2 mo (once infant can make consistent convergence)
  • Adult levels of accommodation reached by 3-4 months of age (infant able to accommodate within a few weeks of birth)
    • First few weeks: infants can make vergence movements, but are unstable and inaccurate and cannot be initiated based on image disparity alone
    • 1 mo: infants can make consistent divergence eye movements
    • 2 mo: infants can make consistent convergence eye movements
      *accommodation and vergence linked
    • 6 mo: vergence eye movements reach adult levels—can be initiated based on disparity alone.

Binocular Vision and Stereopsis

  • 3-5 mo: stereo appears suddenly in infants
  • 4-6 mo: rapid development to adult levels
  • 7 mo: nearly 100% of infants have stereopsis at this point
  • 24 mo: stereoacuity reaches adult levels of 1 minute of arc

Form Reproduction and Perception

  • 4 years: peak of contrast sensitivity function reaches adult levels
  • 7-9 years: overall contrast sensitivity (adult levels) reached and will have a similar sensitivity as adults to low contrast, high spatial frequency gratings.

Temporal Vision

  • 3 mo: The critical flicker frequency of infants reaches adult levels

    Pediatric eye exam

ELEMENTS FOR A PEDIATRIC EYE EXAM

    • History – Basic Elements
    • Pediatric History – School, Development, Pregnancy/Birth History
    • Visual Acuity (most school exam forms require aided and unaided)
    • Cover Test @ Distance and Near (quantification when
      necessary)
    • Stereo Acuity
    • Color Vision* (required for most school exam forms)
    • Near Point of Convergence
    • Extraocular Muscles
    • Confrontation Visual Fields
    • Pupils
    • Dry Retinoscopy/Dry Refraction (if obtainable)
    • Anterior Segment Evaluation (if obtainable)
    • Tonometry
    • Posterior Segment Evaluation
    • Wet Retinoscopy/Refraction

TRICKS AND TREATS

For your preschoolers and toddlers, having an incentive to let the child know about up front is important. Don’t show your entire hand on the flop. In other words, don’t give candy and stickers as soon as the exam starts because it takes away any leverage you have when you are really trying to get the attention and cooperation of the patient during things like retinoscopy or binocular indirect.

Here are some various notes that will serve you well to know:

  • Auto-refraction
    • Overestimates myopia, underestimates hyperopia
    • Kids are notorious focusers – use the auto as a reference point (very helpful to compare values pre- and post-cyclo)
  • Subjective Refraction
    • Based on maturity of the child
    • Younger—should place little emphasis on what you get for refraction
  • Mohindra Retinoscopy
    • NO LIGHTS! Child should only see the light you are holding
    • Child looks at the light
    • Performed at 50 cm, do retinoscopy as normal
    • Adjust by subtracting 1.25 D from what you found to get your final value

Ocular Health

      • Most children are going to be grossly normal—not to be done the same degree as you would in an adult
      • Looking for gross abnormalities (congenital glaucoma, coloboma, conjunctivitis, corneal or lens opacity*) *opacities, should be thinking Form Deprivation Amblyopia

Assessing Ocular Health

  • Pupillary Reflex
    • Kids will often look at lights or things that are visually interesting and mobile. One great way to do cover test on a really young patient is to sit right in front of the child, putting one hand against the forehead and the other one holding the transilluminator. Then, with your thumb as the occluder, perform cover test as usual. Your thumb is the perfect size to cover just enough of the child’s eye to get an idea of whether any tropias or phorias are present.
    • If the child is distracted by your arm or hand, try covering and uncovering the transilluminator a few times. This flashes the light and pulls the attention back to you.
  • Burton Lamp
    • Adds more illumination on front surface of the eye to examine more thoroughly.
  • Portable Slit Lamp
    • If not, you can always try to use a traditional slit lamp, but little kids are generally too short to sit and reach the chin rest. Consider having them sit on mom/dad’s lap for this.
  • Intraocular Pressure
    • TonoPen (if able to keep patient’s head stable)
    • Tactile (using fingers)
      -Done most of the time in really young kids
      -Looking for symmetry
      -Record as “Soft and Equal by palpation OU”
    • Goldmann Applanation Tonometer—depends on cooperation, but at least try on ages 10+
  • Dilated Fundus Exam
    • Avoid the word “drops” (“The D-word!”)

      -Alternatives?
      “I’m going to put a twinkle in your eye”
      “I’m going to put some water in your eye”
      -Can also tell them it can be done with eyes closed (just be sure they blink enough to get them in!)
    • Smaller body weight = use lowest potency possible
      -If worried about systemic absorption, have the patient do nasolacrimal occlusion
    • Get the eye that is closest to the parent or guardian first (kids tend to lean in to the person holding them)
  • Dilating Agents:
    1. Phenylephrine 2.5%
      • Adrenergic Agonist–Promotes PS activity
      • MOA: direct-acting adrenergic agonist, rapid dilation with short period of action
      • Risk: potential exists for cardiovascular side effects
      • Should NOT be given to children under 3 and those with a history of cardiovascular problems
    2. Tropicamide 0.5%/1.0%
      • Cholinergic antagonist—blocking Ach, Inhibits PS activity
      • MOA: cholinergic antagonist, rapid dilation with short duration (Safest dilating agent available)
      • Two strengths—these have the same efficacy of dilation, but 0.5% will have less cycloplegic effect
        • 20-35 min to peak (mention to parents the drops will dilate for about 6 hours)
        • Effective for the measurement of refractive error in non-strabismic infants if cyclopentolate is not available or is contraindicated
    3. Cyclopentolate
      • Drug of choice for cycloplegic refraction (dual purpose)
      • MOA: Decrease the ciliary muscle activity on the crystalline lens and diminishes/eliminates fluctuations of accommodation
        • Also serves as a mydriatic, which facilitates dilated fundus examination
        • Standard of care for children with:
          -high amounts of hyperopia
          -greater than 1.00 D of anisometropia
          -strabismus
        • 30-45 min to peak (if possible, wait 30 min before doing/re-checking retinoscopy)
          • PRIMARY PURPOSE/EFFECT: knocks out accommodation
          • SECONDARY PURPOSE/EFFECT: dilation
          • “How long will it last?” Up to 24 hours!

            Additional DFE Pearls:

                • For darkly pigmented eyes, use Tropicamide in addition to cyclopentolate
                  -Most often used with African-American and Hispanic kids

                  • May be a good idea to go ahead and just drop with both (especially if in a peds clinic)
      • 0.5% cyclopentolate = Infants (<12 mo)
        -Corneal sensitivity is often low
      • 1.0% cyclopentolate = children (1 yr and older)
        -Often necessary to use 1.0% tropicamide in addition to cyclopentolate with dark irises
      • 2% cyclopentolate: rarely used
    • DO NOT TELL A CHILD THAT DROPS WILL NOT STING!
      • If you tell a child it will not sting and then it does, you lose all credibility as a trusted adult.
        -You will have a difficult time getting them to cooperate the remainder of the time.
      • Instead, say something like:
        “It will tingle,” or, “It will make your eyes feel a little funny,” or, my favorite, “It will feel like you got some pool water in your eyes for a minute.”
      • I’ve found that if you relate it back to something fun (swimming at the pool or beach), it goes over well with children.
  • Retinoscopy: Tips to help maximize efficiency
    • With ret bars:
      – Try to figure out if you need red or black ret bars first (scope reflex without lenses)
      – Determine axis of astigmatism before putting bars in front
    • With phoropter:
      – Tell the child to “look through the window” or come up with some other way to spark interest in continuing to look through the phoropter.
      – Make sure they are comfortable! Kids are pretty fidgety enough as it is, so having them comfortable will help reduce the number of times they pull away from the phoropter to re-situate. I usually have the child sit as far back on the chair as possible. I’ve found this encourages them to stay more relaxed and allows them to focus on the video or whatever target you have up behind you.

Minimize Distractions

      • Put on something with motion picture and sound. If you have a digital chart, chances are you have the option of playing a movie or short video. If you aren’t sure, definitely spend a few minutes next time you are in clinic to get to know your eye chart! It could cut down on your exam time and make a world of difference!
      • Put up a red/green chart with letters or figures. This gives the child something to do while you try to scan with the retinoscope. It also ensures that they stay looking out at distance instead of accommodating.
        • Ask the child, “Can you tell me what you see on the red side” then, “What about the green side?” 
        • If you have another person in the room with you, they can be changing the targets for the Allen figures. I usually say things like, “Now, you tell me if those pictures change out there because sometimes they change. Is the duck still out there? What about the man on the horse, is he still riding the horse?” It takes some time to get the hang of it, but being able to distract a child during important testing is a MUST!
        • Q: What is the most appropriate method of taking VAs on a 3-year old? A: Lea symbols are probably your best bet; the patient should be able to match.
  • Posterior Seg Eval
    • Indirect Ophthalmoscopy (probably the easiest)
    • Direct Ophthalmoscopy
    • Internal Exam Alternatives
      – Sedation—obviously, as a last resort
      – Eyelid speculum (when might a parent have seen this previously? An ROP baby.)
      – Extended testing—MRI, CT

Cooperation

  • Your exam will be hard if child is hungry or tired, but what if they are asleep? That’s ok! You can still try to examine them this way with BIO or direct ophthalmoscopy.
  • School-aged kids

If the child is being difficult, consider other factors (ex: neuro disorder, behavioral disorder, etc?). Don’t forget to ask about how the child is doing in school. If mom or dad reports that the patient is very avoidant with homework or near tasks, like reading, consider the need for correction of a refractive error first. This is the most important step in ruling out vision as the primary cause.

Know when to fold!

    • These scenarios include:
      • If you cannot guide a child’s behavior, results may be less reliable. In addition, the parent may not have confidence in your results.
      • If the patient is uncooperative, you can plan to have the child come back on another day.
      • If it is the dilating drop that cause the child’s behavior to change, reschedule for another day and have the parent or guardian put the drops in prior to the appointment.
        • Helpful to instill the drops before the patient wakes up (on the eyelids).
        • Important: show parent/guardian how to instill the drops. Don’t just assume they are comfortable with it or have done it before!

          Exam Frequency

              • Birth-2 years: should be seen 6-12 months of age
              • Age 3-5 years: at least once
              • Age 6-18 years: before first grade, annually thereafter
                *Any child considered “at-risk” for ocular disease or disorder should be seen as recommended by an eye care professional

PEDIATRIC PRESCRIBING: Quick Notes

  • Normal progression of myopia: -0.5 D per year once they hit school age
  • Atropine for myopia control: dose?
    – Use the weakest dosage–fewest SE and less rebound at 1 yr.
    – Downside? Must be compounded in the US and is expensive ($90/mo)
  • If you code for amblyopia suspect, have the patient RTC in 4-6 mo for cyclo ret. The follow-up visit would be considered a medical visit.
  • Plateau in visual improvement with a spec rx is around 16 weeks (4 months). This is important to know for your amblyopic patients.
  • Never prescribe atropine AND a bifocal to be used at the same time (negates)
  • Prescribe all astigmatism in Manifest Rx if patient is greater than 3.5 years old
    Example:
    Dry: +1.00-4.50×180 OD, OS / Wet: +3.00-4.50×180 OD, OS
    20/30 OU at distance and near.
    -Would you prescribe the full Rx?
    The plateau for astigmatic changes in children is around 3.5 years old, so recommended to give full astigmatic power, but cut the plus (usually do not cut more than 1.5 D of plus)
  • The amount of aniso observed in a patient should be the same before and after cyclo

Do you have any tips and tricks of your own to add? Comment below!


Recommendations and examination techniques in this article do not represent standard of care and are intended to assist in the decision-making process of the clinician. Patient care and treatment should always be based on a clinician’s independent and professional judgement, and should weigh in the patient’s unique case in compliance with state laws and regulations.