optic cup

(noun)

During embryonic development of the eye, the outer wall of the bulb of the optic vesicles becomes thickened and invaginated, converting it to a cup consisting of two strata of cells. These strata are continuous with each other at the cup margin, which ultimately overlaps the front of the lens and reaches as far forward as the future aperture of the pupil.

Related Terms

Examples of optic cup in the following topics:

  • Development of Vision

    • The lens then acts as an inducer back to the optic vesicle to transform it into the optic cup and back to the epidermis to transform it into the cornea.
    • The optic cup then delaminates into two layers: the neural retina and the retinal pigment epithelium.
    • The periocular mesenchyme migrates inward during the formation of the optic cup and is critical for the induction of the retinal pigment epithelium and the optic nerve.
    • Iris is formed from the optic cup cells.
    • During embryonic development of the eye, the outer wall of the bulb of the optic vesicles becomes thickened and invaginated, and the bulb is thus converted into a cup, the optic cup.

  • Optic (II) Nerve

    • The optic nerve is also known as cranial nerve II.
    • The optic nerve is the second of twelve paired cranial nerves.
    • As a consequence, optic nerve damage produces irreversible blindness.
    • The optic nerve leaves the orbit, which is also known as an eye socket, via the optic canal, running posteromedially toward the optic chiasm, where there is a partial decussation (crossing) of fibers from the nasal visual fields of both eyes.
    • An illustration of the brain highlighting the optic nerve and optic tract.

  • Orbits

    • To the rear of the orbit, the optic foramen opens into the optical canal through which the optic nerve and ophthalmic artery pass.
    • Finally, the sphenoid bone forms the posterior wall of the orbit and also contributes to the formation of the optic canal.

  • Fourth Week of Development

    • The optical vesicle (which will eventually become the optic nerve, retina, and iris) forms at the basal plate of the prosencephalon.
    • A white circle represents the area of the optical vesicle.

  • Foramina

    • Optic foramen: Located in the sphenoid, it allows the passage of the ophthalmic artery and nerve from the optic canal into the orbit.

  • Brief Overview of Cranial Nerves

    • The terminal nerves, olfactory nerves (I) and optic nerves (II) emerge from the cerebrum or forebrain, and the remaining ten pairs arise from the brainstem, which is the lower part of the brain.
    • However, on a structural level, the olfactory, optic, and terminal nerves are more accurately considered part of the central nervous system.
    • The optic nerve (II): This nerve carries visual information from the retina of the eye to the brain.

  • Trochlear (IV) Nerve

    • Other than the optic nerve (cranial nerve II), it is the only cranial nerve that decussates (crosses to the other side) before innervating its target.
    • Lesions of all other cranial nuclei affect the ipsilateral side (except of course the optic nerve, cranial nerve II, which innervates both eyes).

  • Physiological Changes

    • A woman's breasts grow during pregnancy, usually one to two cup sizes, but possibly larger.
    • A woman who wore a C cup bra prior to her pregnancy may need to buy an F cup or larger bra while nursing.

  • Sensation to Perception

    • These are two optical illusions that illustrate how perception may differ from reality.

  • Olfactory (I) Nerve

    • The olfactory nerve is the shortest of the 12 cranial nerves and only one of two cranial nerves (the other being the optic nerve) that do not join with the brainstem.