Strabismus and Paediatric Ophthalmology
Concept anchors
Amblyopia is reduced acuity from abnormal visual experience, classified as strabismic, refractive (anisometropic or bilateral), or deprivation. Treat by correcting refractive error, then occlusion or atropine penalisation, with adherence to the critical period. Strabismus assessment uses cover testing, Krimsky and Hirschberg estimates, versions and ductions; suppression and anomalous retinal correspondence affect sensory outcomes.
Common entities
Infantile esotropia presents before 6 months with a large constant angle and cross-fixation; accommodative esotropia appears at 2 to 3 years with high hyperopia and is treated with glasses; intermittent distance exotropia shows a distance deviation with divergence on cover testing; Duane syndrome has limited abduction with globe retraction; superior oblique palsy shows a positive Bielschowsky head tilt test.
Paediatric red flags
Leukocoria differential: retinoblastoma, persistent fetal vasculature, Coats disease, toxocariasis, congenital cataract. Congenital glaucoma (buphthalmos, corneal edema, photophobia, tearing) requires urgent surgery. Congenital nasolacrimal duct obstruction usually resolves by 12 months; probing after that.
Traps
Screening intervals for retinopathy of prematurity, timing of congenital cataract surgery, and differentiating orbital from preseptal cellulitis. Amblyopia treatment can be effective beyond the classic critical period, though results decline with age.
Worked example
A 3-year-old with a 30 prism dioptre esotropia that fully corrects with +4.50 D spectacles has fully accommodative esotropia - glasses alone are the treatment, not surgery.