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.
Diagnosis
The initial amblyopia evaluation (history and physical examination) includes all components of the comprehensive pediatric ophthalmic evaluation (American Academy of Ophthalmology Basic and Clinical Science Course Subcommittee, 2007), with special attention to the potential risk factors for amblyopia, such as a positive family history for strabismus, amblyopia, or media opacity.
History
Although a thorough history generally includes the following items, the exact composition varies with the patient's particular problems and needs:
- Demographic data, including identification of parent/caregiver, and patient's gender and date of birth [A:III]
- 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]
- Current eye problems [A:III]
- Ocular history, including prior eye problems, diseases, diagnoses, and treatments [A:III]
- Systemic history; birth weight; prenatal and perinatal history that may be pertinent (e.g., alcohol, tobacco, and drug use during pregnancy); past hospitalizations and operations; and general health and development [A:III]
- Current medications and allergies [A:III]
- Review of systems [B:III]
Examination
The eye examination consists of an assessment of the physiological function and the anatomic status of the eye and visual system. Documentation of the child's level of cooperation with the examination can be useful in interpreting the results and in making comparisons among the examinations over time. In general, the examination may include the following elements:
- Assessment of visual acuity and fixation pattern [A:III]
- Ocular alignment and motility [A:III]
- Red reflex or binocular red reflex (Brückner) test [A:III]
- Pupil examination [A:III]
- External examination [A:III]
- Anterior segment examination [A:III]
- Cycloplegic retinoscopy/refraction [A:III]
- Funduscopic examination [A:III]
- Binocularity/stereoacuity testing [A:III]
Management
Success rates of amblyopia treatment may decline with increasing age (Scheiman et al., 2005; Mohan, Saroha, & Sharma, 2004) [A:I]. However, all children should be considered for treatment of amblyopia regardless of age although the difficulty of treatment for both the patient and caregiver should not be underestimated (Dixon-Woods, Awan, & Gottlob, 2006; Yang & Lambert, 1995; Koklanis, Abel, & Aroni, 2006). The prognosis for attaining and maintaining essentially normal vision in an amblyopic eye depends on many factors, including the age of the patient at detection, the cause and severity of amblyopia, the history of previous treatment (Scheiman et al., 2005), the duration of amblyopia, and compliance with treatment.
The following therapies are used alone or in combination as required to achieve the therapeutic goal.
- Optical correction (Scheiman et al., 2005; Chen et al., 2007; Cotter et al., 2006) [A:I]
- Occlusion (Repka et al., 2005; Pediatric Eye Disease Investigator Group, 2002; Pediatric Eye Disease Investigator Group, "A comparison," 2003; Repka et al., 2003) [A:I]
- Penalization (Repka et al., 2005; Pediatric Eye Disease Investigator Group, 2002; Pediatric Eye Disease Investigator Group, "A comparison," 2003; Repka et al., 2004; Pediatric Eye Disease Investigator Group, "The course of moderate amblyopia," 2003) [A:I]
- Surgery to treat the cause of the amblyopia (Lam, Repka, & Guyton, 1993; Paysse et al., 2006; Reese & Weingeist 1987) [A:III]
In general, occlusive adhesive patches should be used during the initial therapy in many cases of amblyopia [A:III]; however, in mild to moderate amblyopia, penalization with atropine drops has been shown to be an effective alternative (Repka et al., 2005; Pediatric Eye Disease Investigator Group, 2002; Pediatric Eye Disease Investigator Group, "A comparison," 2003; Repka et al., 2004; Pediatric Eye Disease Investigator Group, "The course of moderate amblyopia," 2003)
Follow-up Evaluation during Treatment
The purpose of the follow-up evaluations is to monitor the response to therapy and adjust the treatment plan as necessary. Follow-up evaluation includes interval history and tolerance to therapy with appropriate examinations and testing as indicated.
The frequency of follow-up evaluations will depend on the age of the patient, severity of the amblyopia, and intensity of occlusion therapy (high versus low percentage).
Patients who are functionally monocular should wear proper protective eyewear full time, even if they do not require corrective lenses [A:III]. A frame approved by the American National Standards Institute Standard No. Z87.1 with polycarbonate lenses should be worn for daily wear and low-eye-risk sports [A:III]. For most ball and contact sports, polycarbonate sports goggles should be worn, and head and face protection should be added for higher risk activities (American Academy of Pediatrics and American Academy of Ophthalmology, 2003; Vinger, 1998) [A:III]. Functionally monocular individuals should use approved protective eyewear when participating in contact sports or other potentially harmful activities, such as those that involve pellet guns, paintballs, and personal use of fireworks (Saunte & Saunte, 2006; Kennedy, Ng, & Duma, 2006; Endo, Ishida, & Yamaguchi, 2001; Fleischhauer et al, 1999; Greven & Bashinsky, 2006; Listman, 2004; Hargrave, Weakley, & Wilson, 2000) [A:III]. Special goggles, industrial safety glasses, side shields, and full-face shields should be used in these cases [A:III]. Functionally monocular patients should be aware of the need to have regular eye examinations throughout their lives [A:III].
Counseling and Referral
Amblyopia 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 the parent/caregiver [A:III]. 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. Recommended Amblyopia Follow-Up Evaluation Intervals During Active Treatment Period [A:III]
| Patient Age (years) |
High-Percentage Occlusion (70% or more of waking hours/>6 hours per day) |
Low-Percentage Occlusion (<70% of waking hours/<6 hours per day) Penalization |
Maintenance Treatment or Observation |
| 0-1 |
1-4 weeks |
2-8 weeks |
1-4 months |
| 1-2 |
2-8 weeks |
2-4 months |
2-4 months |
| 2-3 |
3-12 weeks |
2-4 months |
2-4 months |
| 3-4 |
4-16 weeks |
2-6 months |
2-6 months |
| 4-5 |
4-16 weeks |
2-6 months |
2-6 months |
| 5-7 |
6-16 weeks |
2-6 months |
2-6 months |
| 7-9 |
8-16 weeks |
3-6 months |
3-12 months |
Note: These follow-up intervals were generated by panel consensus.
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)
