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Strabismus in children
Strabismus is a deviation of the visual axis of one eye; in a child it threatens vision through amblyopia and loss of binocular vision, so any constant strabismus after 4 months of age needs a full examination — including cycloplegic refraction and a fundus examination to exclude an ocular cause such as retinoblastoma.
Why it matters in the exam
The tests examiners like: Hirschberg — the corneal light reflex, each 1 mm of displacement equals roughly 7 degrees (about 15 prism dioptres); cover-uncover — detects a manifest deviation (tropia), when the covered eye moves on uncovering; alternate cover — detects a latent deviation (phoria) as well. Pseudoesotropia in an infant with a broad nasal bridge and epicanthic folds — the reflex is symmetrical. Intermittent deviation up to 3–4 months of age may be normal.
The main types: infantile esotropia — before 6 months, a large constant angle, cross-fixation, a small refractive error; treatment is surgical, usually before age two. Accommodative esotropia — at age 2–3, with hyperopia, disappearing with full glasses from cycloplegic refraction; when the deviation is larger for near (high AC/A) — bifocals. Intermittent exotropia — an eye that drifts out with fatigue or illness, a child who closes one eye in sunlight; follow-up, amblyopia treatment and surgery when control deteriorates.
Special forms: Duane syndrome — limited abduction, globe retraction and narrowing of the fissure on adduction, common in the left eye and in girls, without double vision; Brown syndrome — limited elevation in adduction from the superior oblique tendon. New strabismus with limited movement in an older child, double vision or headache requires imaging for a suspected tumour or raised intracranial pressure. Order of treatment: correct the refraction, treat amblyopia, and only then surgery to align.
Key points
- Constant strabismus after 4 months — full examination.
- Hirschberg: 1 mm ≈ 7 degrees.
- Infantile esotropia → surgery before age two.
- Accommodative esotropia → full glasses.
- Order: refraction, amblyopia, surgery.
Summary table
| Type | Age | Finding | Treatment |
|---|---|---|---|
| Infantile esotropia | Before 6 months | Large angle, cross-fixation | Surgery, usually before age two |
| Accommodative esotropia | Age 2–3 | Hyperopia, improves with glasses | Full glasses; bifocals for high AC/A |
| Intermittent exotropia | Preschool | Drifts out when tired, closes an eye in sun | Follow-up; surgery if it deteriorates |
| Duane syndrome | From birth | Limited abduction, globe retraction | Usually follow-up; surgery for marked head posture |
| Pseudoesotropia | Infant | Epicanthus, symmetrical Hirschberg | Reassurance and follow-up |
A free exam question
במה מהבאים סביר שהמנתח ייתקל בניתוח פזילה של ילד עם תסמונת דווין )syndrome Duane(? (the question as examined, in Hebrew)
- א. absence of the lateral rectus
- ב. Fibrotic lateral rectus
- ג. Duplication of the lateral rectus
- ד. Tight and broadly inserted lateral rectus
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Sources
- AAO Preferred Practice Pattern: Esotropia and Exotropia, 2022 — Evaluation and management
- AAO Basic and Clinical Science Course, Section 6: Pediatric Ophthalmology and Strabismus, 2024-2025 — Esodeviations, exodeviations and special forms of strabismus
- Kanski's Clinical Ophthalmology, 9th edition (2020) — Strabismus
Sources are given for further reading; the text is written afresh and not copied from them.
Reviewed by the Examqo AI Professor · 2026-11-06. The text may contain errors; when in doubt, check the source.