Paediatric
Optic Nerve Hypoplasia
Also known as: optic nerve hypoplasia, ONH, small optic disc, double ring sign, septo-optic dysplasia, de Morsier, optic disc hypoplasia, congenital visual impairment
Filed as: Urgent
Source-cited from the record's own evidence list. Clinical content programme led by Dr Ankit Mathur, PhD, Grad Cert Ocu Thera, B.S. Optom. How the clinical content is governed
Clinical decision support only
Overview
Congenital underdevelopment of the optic nerve, and one of the commonest causes of congenital visual impairment. The point that matters most in primary care is that THIS IS AN ENDOCRINE PROBLEM PRESENTING AS AN EYE SIGN. Reported associations include hypothalamic dysfunction in around 69% of unilateral and 81% of bilateral cases, growth hormone deficiency in about 70%, ACTH deficiency in about 27% — which carries a risk of hypoglycaemia and adrenal crisis — and developmental delay in about 75%.
Recognition
Symptoms: what patients report
- Poor vision or poor visual behaviour, often noticed in infancy.
- Nystagmus in bilateral cases.
- Strabismus in unilateral or asymmetric cases.
- Parents may report no eye symptoms at all where the deficit is unilateral and the child compensates.
Signs: what the examination shows
- A small, pale optic disc, often with a surrounding pigmented or depigmented ring — the 'double ring sign'.
- A reduced disc-to-macula / disc-diameter ratio; a ratio below approximately 0.35 supports the diagnosis.
- Tortuous retinal vessels relative to the small disc.
- Nystagmus (bilateral disease) or strabismus (unilateral disease).
- Visual acuity ranging from near-normal to no light perception, and frequently a visual field defect.
What OptoGuide™ covers for optic nerve hypoplasia
- Pattern reasoning: what this combination of findings points to, and its differentiators
- Don't-miss risks and escalation triggers
- Management tiers with linked Australian therapeutics
- Referral urgency, specialty, and letter drafting
Sources
- Optic Nerve Hypoplasia — EyeWiki
- RANZCO — Paediatric Referral Guidelines (April 2025)
- Congenital Disorders of the Optic Nerve: Excavations and Hypoplasia. Dutton GN. Eye (London, England). 2004;18(11):1038-48.
- Pituitary deficiencies related to optic nerve hypoplasia and visual acuity. Murray A, Schwartz T, Hornung L, Lawson S. Clinical Endocrinology. 2024;101(5):507-515.
- Neuroimaging and Endocrine Disorders in Paediatric Optic Nerve Hypoplasia. Qian X, Fouzdar Jain S, Morgan LA, et al. The British Journal of Ophthalmology. 2018;102(7):906-910.
Standard texts: Kanski's Clinical Ophthalmology: A Systematic Approach, The Wills Eye Manual.