Article

Postnatal growth of the human optic nerve

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Abstract

PurposeAlthough the length of the average human adult optic nerve (ON) is known, the average length of the normal full-term, newborn ON has never been adequately evaluated, nor has the in vivo growth rate of the human ON been determined. We wanted to identify both the average length of the newborn human ON and its rate of anteroposterior growth.Patients and methodsUsing MRIs from a newly generated set of normal newborn infants rescanned at 1 year, and from different aged groups, we calculated average newborn ON length and growth rate.ResultsThe newborn human ON is 25.3±0.3 mm in length from globe to chiasm, and grows by 80% in length after birth, with maximum speed of elongation occurring in the first 3 years of life, attaining full length by 15 years of age.Conclusion The human ON grows dramatically in the first 3 years of life, and continues to grow for the first two decades. These data are relevant for pediatric treatments that may impede or alter orbital growth in infants, and maximal susceptibility to oncological procedures in early childhood.Eye advance online publication, 15 July 2016; doi:10.1038/eye.2016.141.

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... According to Bernstein et al. (2016), the optic nerve is 43 to 47 mm long from globe to chiasm [21]. For its study, it is divided into four segments (Fig. 4a and 4b): intraocular, intraorbital, intra-canalicular, and intracranial [22]. ...
... According to Bernstein et al. (2016), the optic nerve is 43 to 47 mm long from globe to chiasm [21]. For its study, it is divided into four segments (Fig. 4a and 4b): intraocular, intraorbital, intra-canalicular, and intracranial [22]. ...
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... In humans, myelination starts also before birth but occurs mainly during a long postnatal period. The study of the human optic nerve postnatal growth revealed that the ON elongates by 80% during the 3 firsts postnatal years and reaches its final length only around 15 years old (Bernstein SL et al, 2016). ...
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... optic nerve | lamina | neural progenitor cell niche | eye | postnatal axon growth T he human and rodent optic nerve (ON) connecting the eye and brain grows by 80% postnatally (1,2). Unmyelinated retinal ganglion cell (RGC) axons originating in the retina pass through the optic nerve lamina region (ONLR), the most anterior portion of the optic nerve, before myelination occurs in the more distal portion of the optic nerve (ON) (3). ...
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... The proximal portions are intraretinal, arise from RGC somata or primary dendrites, join fascicles in the innermost sublayer of the retina (the nerve fiber layer), converge at the optic disk, and range in length up to 3.5 mm in rats and ;20 mm in humans (Ramón y Cajal, 1972;Fukuda, 1977;Curcio and Allen, 1990). The distal extraretinal portions exit the eye, project to numerous subcortical brain areas via the optic nerve, optic chiasm, and optic tract (Berson, 2008;Morin and Studholme, 2014), and are ;20 mm long in rats and 100 mm long in humans (Sumitomo et al., 1969;Matheson, 1970;Lang and Reiter, 1985;Bernstein et al., 2016). ...
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Embryology of the afferent visual system
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