Page 1926 - Saunders Comprehensive Review For NCLEX-RN

fovea centralis, the area of sharpest and keenest
vision, where most acute vision occurs.
3. Its functions include central vision, night and color
vision, and motion detection.
H. Aqueous humor
1. A clear, watery fluid that fills the anterior and
posterior chambers of the eye
2. It is produced by the ciliary processes, and the fluid
drains into the canal of Schlemm.
3. The anterior chamber lies between the cornea and the
iris.
4. The posterior chamber lies between the iris and the
lens.
I. Canal of Schlemm: Passageway that extends completely around
the eye; it permits fluid to drain out of the eye into the systemic
circulation so that a constant intraocular pressure (IOP) is
maintained.
J. Lens
1. Transparent convex structure behind the iris and in
front of the vitreous body
2. The lens bends rays of light so that the light falls on
the retina.
3. The curve of the lens changes to focus on near or
distant objects.

K. Conjunctivae: Thin, transparent mucous membranes of the

eye that line the posterior surface of each eyelid, located over the
sclera
L. Lacrimal gland: Produces tears that are drained through the
punctum into the lacrimal duct and sac
M. Eye muscles
1. Muscles do not work independently; each muscle
works with the muscle that produces the opposite
movement.
2. Rectus muscles exert their pull when the eye turns
temporally.
3. Oblique muscles exert their pull when the eye turns
nasally.

N. Nerves

1. Cranial nerve II: Optic nerve (sight)
2. Cranial nerve III: Oculomotor (eye movement)
3. Cranial nerve IV: Trochlear (eye movement)
4. Cranial nerve VI: Abducens (eye movement)
O. Blood vessels
1. The ophthalmic artery is the major artery supplying
the structures in the eye.

1926