Ratings of importance to the care process (A-C) and ratings of strength of evidence (I-III) are defined at the end of the "Major Recommendations" field.
Esotropia
Diagnosis
The purpose of the comprehensive strabismus evaluation is to make the diagnosis, establish baseline status, and determine appropriate initial therapy. The possibility of restrictive, paralytic, or other neurologic causes (especially head trauma or increased intracranial pressure) for the strabismus should be considered. Because binocular vision can degrade rapidly in young children, resulting in suppression and anomalous retinal correspondence, early diagnosis and treatment are essential (Dickey & Scott, 1988; Fawcett, Leffler, & Birch, 2000; Wilson, Bluestein, & Parks, 1993).
The examination of a patient who has childhood-onset strabismus includes all components of the comprehensive pediatric or adult ophthalmic evaluation in addition to the sensory, motor, refractive, and accommodative functions (American Academy of Ophthalmology Pediatric Ophthalmology/Strabismus Panel, 2007; American Academy of Ophthalmology Preferred Practice Patterns Committee, 2005).
History
Although a thorough history generally includes the following items, the exact composition varies with the patient's particular problems and needs:
- Demographic data, [A:III] including identification of parent/caregiver, and patient's gender and date of birth
- Documentation of identity and relationship of historian [B:III]
- The identity of other pertinent health care providers [A:III]
- The chief complaint and reason for the eye evaluation [A:III], including date of onset and frequency of the ocular misalignment; which eye is deviated and in what direction; the presence or absence of diplopia, squinting, or other visual symptoms. Review of photographs of the patient may be helpful.
- Ocular history [A:III], including other eye problems, injuries, diseases, surgery, and treatments (including eyeglasses and/or amblyopia therapy)
- Systemic history; birth weight; prenatal and perinatal history that may be pertinent (e.g., alcohol, drug, and tobacco use during pregnancy); past hospitalizations and operations; general health and development [A:III]
- Pertinent review of systems, [B:III] including history of head trauma and relevant systemic diseases
- Family and social history [A:III], including eye conditions (strabismus, amblyopia, type of glasses and history of wear, extraocular muscle surgery or other eye surgery, and genetic diseases)
- Current medications and allergies [A:III]
Examination
The comprehensive strabismus examination should include the following elements:
- Assessment of fixation pattern and visual acuity in each eye [A:III]
- Ocular alignment and motility at distance and near [A:III]
- Extraocular muscle function (ductions and versions including incomitance, such as A and V patterns) [A:III]
- Detection of nystagmus [A:III]
- Sensory testing [A:III]
- Cycloplegic retinoscopy/refraction [A:III]
- Fundoscopic examination [A:III]
Documentation of the child's level of cooperation with the examination can be useful in interpreting the results and in making comparisons between examinations.
Management
All forms of esotropia should be considered for treatment. [A:III] Ocular alignment should be established as soon as possible, especially in young children, to maximize binocularity (Bateman, Parks, & Wheeler, "Discriminant analysis of congenital esotropia surgery," 1983; Birch et al., 2004), prevent or facilitate treatment of amblyopia (Dickey et al., 1991; Sperduto et al., 1983), and normalize appearance. [A:III] In almost all cases, clinically important refractive errors should be corrected. [A:III] Amblyopia treatment is usually started before surgery, because this may reduce the angle of strabismus (Koc et al.,2006) or increase the likelihood of good postoperative binocularity (Birch et al., 2004; Weakley & Holland, 1997) [A:III]
Choice of Therapy
The following treatment modalities are used alone or in combination as required to achieve the therapeutic goal:
- Correction of refractive errors (Pediatric Eye Disease Investigator Group, 2002) [A:I]
- Bifocals (Ludwig, Parks, & Getson, 1989) [A:II]
- Prism therapy (Repka, Connett, & Scott, 1996; "Efficacy of prism adaptation," 1990) [A:II]
- Amblyopia treatment (Weakley & Holland, 1997) [A:III]
- Extraocular muscle surgery (Bateman, Parks, & Wheeler, "Discriminant analysis of acquired esotropia surgery," 1983) [A:III]
Treatment plans are formulated in consultation with the patient and parent/caregiver. The plans should be responsive to their expectations and preferences [A:III], including the family's/caregiver's perception of the existing alignment, which may differ from the ophthalmologist's, and what they hope to achieve with treatment. It is important that the family/caregiver and ophthalmologist agree on the goals of treatment before surgery is performed.
Follow-up Evaluation
Even when initial treatment results in good ocular alignment, follow-up is essential, since the child remains at high risk for developing amblyopia, losing binocular vision, and having a recurrence of strabismus. Until visual maturity is reached, periodic evaluations are necessary (Bhola et al., 2006). [A:II] During the teenage years, and if the examination has been stable, follow-up evaluations are appropriate every 1 to 2 years thereafter (Scheiman et al., 2005). [A:I] New or changing findings may indicate the need for more frequent follow-up examinations.
Counseling and Referral
Childhood esotropia is a long-term problem that requires commitment from the parent/caregiver and ophthalmologist to achieve the best possible outcome.
The ophthalmologist should discuss the findings of the evaluation with the patient, when appropriate, as well as with the parent/caregiver. The ophthalmologist should explain the disorder and recruit the family in a collaborative approach to therapy. [A:III] Parents/caregivers of pediatric patients who understand the diagnosis and rationale for treatment are more likely to adhere to treatment recommendations (Newsham, 2002; Norman et al., 2003).
Exotropia
Diagnosis
The purpose of the comprehensive strabismus evaluation is to make the diagnosis, establish baseline status, inform the family/caregiver, and determine appropriate therapy. The possibility of restrictive, paralytic, or other neurologic causes (especially head trauma or increased intracranial pressure) for the strabismus should be considered.
The examination of a patient who has childhood-onset strabismus includes all components of the comprehensive pediatric or adult ophthalmic evaluation in addition to the sensory, motor, refractive, and accommodative functions (American Academy of Ophthalmology Pediatric Ophthalmology/Strabismus Panel, 2007; American Academy of Ophthalmology Preferred Practice Patterns Committee, 2005)
History
Although a thorough history generally includes the following items, the exact composition varies with the patient's particular problems and needs.
- Demographic data [A:III], including identification of parent/caregiver, and patient's gender and date of birth
- Documentation of identity and relationship of historian [B:III]
- The identity of other pertinent health care providers [A:III]
- The chief complaint and reason for the eye evaluation, [A:III] including date of onset and frequency of the ocular misalignment; which eye is deviated and in what direction; the presence or absence of diplopia, squinting, or other visual symptoms. Review of photographs of the patient may be helpful.
- Ocular history, [A:III] including other eye problems, injuries, diseases, surgery, and treatments (including eyeglasses and/or amblyopia therapy)
- Systemic history; birth weight; prenatal and perinatal history that may be pertinent (e.g., alcohol, drug, and tobacco use during pregnancy); past hospitalizations and operations; general health and development [A:III]
- Pertinent review of systems, [B:III] including history of head trauma and relevant systemic diseases
- Family and social history, [A:III] including eye conditions (strabismus, amblyopia, type of glasses and history of wear, extraocular muscle surgery or other eye surgery, and genetic diseases)
- Current medications and allergies [A:III]
Examination
The comprehensive strabismus examination should include the following elements:
- Assessment of fixation pattern and visual acuity in each eye [A:III]
- Ocular alignment and motility at distance and near [A:III]
- Extraocular muscle function (ductions and versions including incomitance, such as A and V patterns) [A:III]
- Detection of nystagmus [A:III]
- Sensory testing [A:III]
- Cycloplegic retinoscopy/refraction [A:III]
- Funduscopic examination [A:III]
Documentation of the child's level of cooperation with the examination can be useful in interpreting the results and in making comparisons between examinations.
Management
All forms of exotropia should be considered for treatment. [A:III] In most cases, ocular alignment should be re-established as soon as possible, especially in young children, if the deviation is manifest a large percentage of the time. [A:III] However, the optimal modes of therapy for exotropia, the long-term benefit of early surgical correction, and the superiority of bilateral versus unilateral surgery are not well established (Hatt & Gnanaraj, 2006). Amblyopia is uncommon in patients with intermittent exotropia, but it should be treated if present. [A:III]
Choice of Therapy
The following treatment modalities may be used alone or in combination as required to achieve the therapeutic goal:
- Correcting refractive errors [A:III]
- Overcorrecting minus lenses [A:III]
- Patching (antisuppression therapy) [A:III]
- Amblyopia treatment [A:III]
- Prism therapy [A:III]
- Convergence exercises for convergence insufficiency [A:III]
- Extraocular muscle surgery [A:III]
Follow-up Evaluation
Children with exotropia require follow-up evaluations to monitor the magnitude and frequency of the deviation, visual acuity, and binocularity. The frequency of the follow-up evaluations is based on the age of the child, the ability to obtain an accurate visual acuity, and the control of the deviation. Yearly examinations are appropriate until visual maturity is reached, but they may be reduced in frequency thereafter if the strabismus has been stable. [A:III]
Follow-up evaluation includes interval history, tolerance to treatment (if any), and routine examination and testing of ocular motility.
Counseling and Referral
The ophthalmologist should discuss the findings of the evaluation with the patient, if appropriate, as well as the parent/caregiver. The ophthalmologist should explain the disorder and recruit the family in a collaborative approach to therapy. [A:III] Parents/caregivers of pediatric patients who understand the diagnosis and rationale for treatment are more likely to adhere to treatment recommendations (Newsham, 2002; Norman et al., 2003).
Table. Follow-up Eye Examination Guidelines for Children with Esotropia and Exotropia [A:III]
Age |
Interval |
0-1 year |
3-6 months |
1-5 years |
6-12 months |
5 years |
12-24 months |
Note: More frequent visits may be necessary if amblyopia is present (see the National Guideline Clearinghouse (NGC) summary of the American Academy of Ophthalmology guideline Amblyopia), if patching therapy is being administered, or if there is a recent deterioration of alignment.
Definitions:
Ratings of Importance to the Care Process
Level A, defined as most important
Level B, defined as moderately important
Level C, defined as relevant but not critical
Ratings of Strength of Evidence
Level I: Includes evidence obtained from at least one properly conducted, well-designed randomized controlled trial. It could include meta-analyses of randomized controlled trials.
Level II: Includes evidence obtained from the following:
- Well-designed controlled trials without randomization
- Well-designed cohort or case-control analytic studies, preferably from more than one center
- Multiple-time series with or without the intervention
Level III: Includes evidence obtained from one of the following:
- Descriptive studies
- Case reports
- Reports of expert committees/organization (e.g., Preferred Practice Patterns [PPP] Panel consensus with external peer review)