Optic nerve hypoplasia: Risk factors and epidemiology

Abstract

ABSTRACT.Objectives: To study the epidemiology of optic nerve hypoplasia. Design and Methods: Children with optic nerve hypoplasia and visual impairment were identified through the Swedish Register of Visually Impaired Children. Pre-and perinatal characteristics were obtained from the Medical Birth Registry and by scrutinizing pregnancy and delivery records. Clinical characteristics of children with optic nerve hypoplasia are described. The following risk factors were studied: maternal age, parity, maternal smoking, gestational duration, birth weight, delivery method, Apgar score, maternal disease during pregnancy, drugs used in early pregnancy. Results: Young maternal age, first parity, maternal smoking, preterm birth and factors associated with preterm birth were risk factors for optic nerve hypoplasia. There was an indicated association with the use of fertility drugs and antidepressant drugs. Conclusions: Optic nerve hypoplasia is apparently associated not only with other anomolies, notably of the central nervous system, but also with signs of general disturbance in fetal development.

Congenital disorders of the optic nerve: excavations and hypoplasia

“…47 Risk factors for ONH include young maternal age, first parity, maternal smoking, and preterm birth and its complications. 48 ONH is a known feature of foetal alcohol syndrome in both man [49][50][51] and experimental animal models. 52,53 Superior segmental ONH has been found in three of 34 children born to mothers with type I diabetes.…”

Optic nerve axons: life and death before birth

“…ONH is now probably the most common optic disc anomaly. 19 Estimates of the prevalence have suggested that ONH occurs in 1.8-6.3 per 100 000 births, 18,20 a more recent study 21 from Sweden suggested around 7 per 100 000 births. At least four of every 10 000 children born in the UK will be diagnosed as severely visually impaired or blind (SVI/BL) by their first birthday, increasing to nearly six per 10 000 by the age of 16 years.…”

Developmental abnormalities of the optic nerve and chiasm

“…The baby's mother had a small coloboma in her right eye (2). Repeated aspiration failed to cause a permanent reduction in the size of the cyst (3)(4)(5). 15 Abnormalities of the optic nerve and chiasm Coloboma associated with teratogens Colobomas have occasionally been described in thalidomide, cocaine, and alcohol embryopathies.…”

“…The parents of children with optic disc hypoplasia tend to be young, from poorer socio-economic groups, unemployed, 27 and are smokers. 5 Measurement of the optic disc size remains difficult, but some objectivity can be introduced by comparing ratios of vessel size and optic disc size or the disc-macula to disc diameter ratio. MRI may be better than photographic analysis when compared with clinical examination.…”

“…1 Paediatric ophthalmologists attend to several new cases each year, and it is a significant cause of blindness in childhood, [1][2][3][4][5] possibly with an increasing incidence. 6 Congenital optic nerve defects now account for about 15% of severe visual impairment or blindness in the UK: optic nerve hypoplasia (ONH) alone accounting for 12%.…”