optic stalk

Forell sat on the ground so as to place his eyes at the level of Burgess' optic stalks.

The former optic stalk is then called the optic nerve.

The region of the presumptive posterior midbrain is marked by an arrowhead. os, Optic stalk.

Closure of the choroid fissure in the optic stalk occurs during the seventh week of development.

It is contained within the optic stalk of the eye and extends from the optic disc through the vitreous humor to the lens.

The Bottom Line: the optic stalks are the structures that precede the optic nerves embryologically.

An abnormal development in the optic stalk causes optic disc dysplasia, which is caused by a mutation in the Pax2 gene.

A coloboma is the failure to close the choroid fissure, which is the opening from the ventral side of the retina in the optic stalk.

They project toward the sides of the head, and the peripheral part of each expands to form a hollow bulb, while the proximal part remains narrow and constitutes the optic stalk.

At 14h of development, additional pax[b] expression is detected in the optic stalk, the otic placode, the nephritic primordium and in presumptive commissural interneurons along the hindbrain and the spinal cord.

Additionally, there can be an optic nerve cyst, which is dilation of the optic nerve posterior to the globe; which most likely results from incomplete regression of the primordial optic stalk and the filling of this area with fluid.

Expression studies in mice show that it is expressed in the palate, coloboma in the visual system, and the basal telencephalon, optic stalk, and visual eye fields where it is expressed along with the Shh and Bmp4 genes.

The lens placode is affected by the chordamesoderm making it to invaginate and forms the optic cup composed by an outer layer of neural retina and inner layer the pigmented retina that will unite and form the optic stalk.