Incidence and associated endocrine and neurologic abnormalities of optic nerve hypoplasia

Importance Optic nerve hypoplasia (ONH) is an increasingly recognized cause of congenital blindness in children; however, there is significant discord regarding its incidence and the rate of associated conditions. OBJECTIVE To determine the incidence of ONH and the rate of associated endocrine, neurologic, and developmental abnormalities among a population-based cohort of pediatric patients. DESIGN Retrospective, population-based study. SETTING Olmsted County, Minnesota (95.7%white in 1990). PARTICIPANTS All pediatric residents (aged <19 years) of Olmstead County, diagnosed as having ONH from January 1, 1984, through December 31, 2008. MAIN OUTCOMES AND MEASURES Incidence of ONH and the rate of associated endocrine, neurologic, and developmental abnormalities. RESULTS Optic nerve hypoplasia was diagnosed in 19 pediatric patients during the 25-year study period, for an annual incidence of 2.4 (95%CI, 1.2-3.5) per 100 000 residents younger than 19 years or 1 in 2287 live births. The mean age at diagnosis was 2.1 years, and 10 (53%) patients were male. Commonly associated perinatal conditions included primiparity in 8 patients (42%), premature birth in 6 (32%), and maternal diabetes mellitus in 3 (16%). Of the 19 study patients, 16 (84%) had bilateral involvement at initial examination, 9 (47%) had decreased visual acuity, 8 (42%) had strabismus, and 5 (26%) had nystagmus. Systemic conditions included developmental delay in 12 (63%), neurologic deficits in 10 (53%), and endocrine dysfunction in 5 (26%). CONCLUSIONS AND RELEVANCE This population-based study demonstrated an incidence of ONH of 1 in 2287 live births. More than half of the patients had developmental and neurologic deficits, and one-fourth had a diagnosis of endocrine dysfunction.