Optic_vesicle
Optic vesicle
Sac that protrudes from the embryonic forebrain to form each eye
The eyes begin to develop as a pair of diverticula (pouches) from the lateral aspects of the forebrain. These diverticula make their appearance before the closure of the anterior end of the neural tube;[1][2] after the closure of the tube around the 4th week of development, they are known as the optic vesicles. Previous studies of optic vesicles suggest that the surrounding extraocular tissues – the surface ectoderm and extraocular mesenchyme – are necessary for normal eye growth and differentiation.[3]
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, which goes on to form the optic nerve.[4][5]