Preterm birth interrupts normal neurologic tissue development, resulting in specific neurologic sequelae in infancy and childhood, and ocular effects can be among them. An increased cup-to-disc (c/d) ratio and pRNFL thinning are associated with different pathologies of the optic nerve head (ONH) and particularly with glaucoma. A recent study provides new evidence that fetal origins influence adults´ ONH configuration. Individuals born prematurely revealed larger vertical c/d ratio compared with subjects born at full-term. This could put preterm individuals at risk of degenerative ONH diseases or being incorrectly diagnosed with glaucoma due to the enlarged parameter.
The current study included 743 eyes of 393 individuals born preterm and full-term (mean age: 28.4, 223 females) from the Gutenberg Prematurity Eye Study, a retrospective cohort study with a prospective ophthalmologic examination of adults (ages 18 to 52) in Germany. The researchers assessed vertical c/d, optic disc area and torted and tilted discs and compared each factor with that of individuals with retinopathy of prematurity (ROP) who received treatment, an ROP group without treatment and groups of individuals of different gestational ages without ROP (gestational age ≤28 weeks, gestational age 29 to 32 weeks, gestational age 33 to 36 weeks and gestational ≥37 weeks [control group]).
The vertical c/d ratio was significantly larger in subjects with a gestational age ≤28 weeks without ROP compared with the full-term control group (gestational age ≥37 weeks). Subjects with ROP without treatment also had a larger vertical c/d, while those with ROP treatment showed a smaller vertical c/d than the full-term control group. In addition, individuals with ROP treatment were more likely to have a tilted disc than the full-term control group.
It is unclear whether the larger vertical cup-to-disc ratio in former preterm individuals leads to an increased risk for optic nerve diseases, such as glaucoma, or whether it is only a maturation disorder with an enlarged vertical c/d that may lead to an increased risk of being incorrectly diagnosed with glaucoma. Also, the researchers noted that the effects on glaucoma development may be underestimated because the participants are relatively young, and glaucoma prevalence is typically low in this age range.
“Longitudinal observations of older study participants may show a better correlation between birth history, optic nerve morphology and development of glaucoma later in life,” they wrote in their paper.
Nevertheless, the study concluded that fetal origins influence adults´ ONH configuration.
Fieß A, Gißer S, Mildenberger E, et al. Optic nerve head morphology in adults born extreme, very and moderate preterm with and without retinopathy of prematurity: results from the Gutenberg Prematurity Eye Study. Am J Ophthalmol. March 11, 2022. [Epub ahead of print].