Postnatal growth of the human optic nerve

Abstract

Purpose Although 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 methods Using 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. Results The 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.

Retinal hypoplasia and degeneration result in vision loss in Friedreich ataxia

“…Overall, many children with FRDA had thin RNFLs compared to age matched controls, which is suggestive of hypoplasia rather than simply degeneration. 28 This finding resembles observations from somatosensory systems in FRDA, in which large fiber sensory function is largely absent at presentation and further promotes the increasingly supported hypothesis of a developmental contribution to FRDA pathophysiology. [29][30][31] In addition, RNFL thickness was heterogenous among subjects and was predicted by disease burden such that subjects with longer GAAs and longer disease duration had thinner RNFLs, an indication of further degeneration over time.…”

“…Surprisingly, unlike most clinical measures of neurological progression in FRDA in which children present only minimally affected or even un‐affected, RNFLs were significantly thin around the time of presentation. Overall, many children with FRDA had thin RNFLs compared to age matched controls, which is suggestive of hypoplasia rather than simply degeneration 28 . This finding resembles observations from somatosensory systems in FRDA, in which large fiber sensory function is largely absent at presentation and further promotes the increasingly supported hypothesis of a developmental contribution to FRDA pathophysiology 29–31 …”

The optic nerve lamina region is a neural progenitor cell niche

“…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).…”

Anatomy of the optic nerve based on cadaveric dissections and its neurosurgical approaches: a comprehensive review

“…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.…”