Eye

Bruch's membrane is the innermost layer of the choroid.

A cataract is a clouding of the lens in the eye leading to a decrease in vision.

Intraocular pressure (IOP) is the fluid pressure inside the eye.

The lens is a transparent, biconvex structure in the eye that, along with the cornea, helps to refract light to be focused on the retina.

The evil eye is a curse believed to be cast by a malevolent glare, usually given to a person when they are unaware.

The sclera and cornea form the fibrous tunic of the bulb of the eye; the sclera is opaque, and constitutes the posterior five-sixths of the tunic; the cornea is transparent, and forms the anterior sixth.

An eyelid is a thin fold of skin that covers and protects the human eye.

The ciliary body is a part of the eye that includes the ciliary muscle, which controls the shape of the lens, and the ciliary epithelium, which produces the aqueous humor.

In anatomy, the orbit is the cavity or socket of the skull in which the eye and its appendages are situated.

The optic disc or optic nerve head is the point of exit for ganglion cell axons leaving the eye.

The pigmented layer of retina or retinal pigment epithelium (RPE) is the pigmented cell layer just outside the neurosensory retina that nourishes retinal visual cells, and is firmly attached to the underlying choroid and overlying retinal visual cells.

The outer plexiform layer (external plexiform layer) is a layer of neuronal synapses in the retina of the eye.

The anterior segment is the front third of the eye that includes the structures in front of the vitreous humour: the cornea, iris, ciliary body, and lens.

The posterior segment is the back two-thirds of the eye that includes the anterior hyaloid membrane and all of the optical structures behind it: the vitreous humor, retina, choroid, and optic nerve.

The retinal nerve fiber layer (nerve fiber layer, stratum opticum, RNFL) is formed by the expansion of the fibers of the optic nerve; it is thickest near the porus opticus, gradually diminishing toward the ora serrata.

The elements composing the Layer of Rods and Cones (Jacob’s membrane) in the retina of the eye are of two kinds, rod cells and cone cells, the former being much more numerous than the latter except in the macula lutea.

The iris dilator muscle (pupil dilator muscle, pupillary dilator, radial muscle of iris, radiating fibers), is a smooth muscle of the eye, running radially in the iris and therefore fit as a dilator.

The macula or macula lutea (from Latin macula, "spot" + lutea, "yellow") is an oval-shaped pigmented area near the center of the retina of the human eye.

A simple eye (sometimes called a pigment pit) refers to a type of eye form or optical arrangement that contains a single lens.

The capillary lamina of choroid or choriocapillaris is a layer of capillaries that is immediately adjacent to Bruch's membrane in the choroid.

The cornea is the transparent front part of the eye that covers the iris, pupil, and anterior chamber.

The pupil is a hole located in the centre of the iris of the eye that allows light to strike the retina.

A redout occurs when the body experiences a negative g-force sufficient to cause a blood flow from the lower parts of the body to the head.

Astigmatism is a type of refractive error in which the eye does not focus light evenly on the retina.

The iris (plural: irides or irises) is a thin, circular structure in the eye, responsible for controlling the diameter and size of the pupil and thus the amount of light reaching the retina.

The sclera, also known as the white of the eye, is the opaque, fibrous, protective, outer layer of the eye containing collagen and elastic fiber.

Eye color or eye colour is a polygenic phenotypic character determined by two distinct factors: the pigmentation of the eye's iris and the frequency-dependence of the scattering of light by the turbid medium in the stroma of the iris.

The ciliary muscle /ˈsɪli.

The choroid, also known as the choroidea or choroid coat, is the vascular layer of the eye, containing connective tissue, and lying between the retina and the sclera.

The conjunctiva lines the inside of the eyelids and covers the sclera (the white of the eye).

The uvea (Lat. uva, grape), also called the uveal layer, uveal coat, uveal tract, or vascular tunic, is the pigmented middle of the three concentric layers that make up an eye.

Hyaloid canal (Cloquet's canal and Stilling's canal.) is a small transparent canal running through the vitreous body from the optic nerve disc to the lens.

The iris sphincter muscle (pupillary sphincter, pupillary constrictor, circular muscle of iris, circular fibers) is a muscle in the part of the eye called the iris.

The corneal endothelium is a single layer of cells on the inner surface of the cornea.

A greyout (US English grayout) is a transient loss of vision characterized by a perceived dimming of light and color, sometimes accompanied by a loss of peripheral vision.

The meibomian glands (or tarsal glands) are a special kind of sebaceous gland at the rim of the eyelids inside the tarsal plate, responsible for the supply of meibum, an oily substance that prevents evaporation of the eye's tear film.

Nystagmus is a condition of involuntary (or voluntary, in rare cases) eye movement, acquired in infancy or later in life, that may result in reduced or limited vision.

The ciliary processes are formed by the inward folding of the various layers of the choroid, i.

The outer nuclear layer (or layer of outer granules or external nuclear layer), is one of the layers of the vertebrate retina, the light-detecting portion of the eye.

The external limiting membrane (or outer limiting membrane) is one of the ten distinct layers of the retina of the eye.

The inner plexiform layer is an area of the retina that is made up of a dense reticulum of fibrils formed by interlaced dendrites of retinal ganglion cells and cells of the inner nuclear layer.

The inner nuclear layer or layer of inner granules is made up of a number of closely packed cells, of which there are three varieties, viz.

The inner limiting membrane is the boundary between the retina and the vitreous body, formed by astrocytes and the end feet of Müller cells.

The ganglion cell layer (ganglionic layer) is a layer of the retina that consists of retinal ganglion cells and displaced amacrine cells.

The stroma of the iris is a fibrovascular layer of tissue.

Schlemm's canal is a circular lymphatic-like vessel in the eye that collects aqueous humor from the anterior chamber and delivers it into the episcleral blood vessels via aqueous veins.

An eyelash or simply lash is one of the hairs that grows at the edge of the eyelid.

Stye, also known as hordeolum, is an infection of an oil gland in the eyelid.

The ora serrata is the serrated junction between the retina and the ciliary body.

The zonule of Zinn (Zinn's membrane, ciliary zonule) (after Johann Gottfried Zinn) is a ring of fibrous strands connecting the ciliary body with the crystalline lens of the eye.

The lacrimal apparatus is the physiological system containing the orbital structures for tear production and drainage.

Nasolacrimal duct obstruction (NLDO) is the obstruction of nasolacrimal duct and may be either congenital or acquired.

The fovea centralis (the term fovea comes from the Latin, meaning pit or pitfall) is a small, central pit composed of closely packed cones in the eye.

Eye tracking is the process of measuring either the point of gaze (where one is looking) or the motion of an eye relative to the head.

Epicanthic fold (/ɛpɪˌkænθɪkˈfoʊld/), epicanthal fold, epicanthus, and eye fold are names for a skin fold of the upper eyelid, covering the inner corner (medial canthus) of the eye.

The retina (UK /ˈrɛtɪnə/ RET-i-nə, US /ˈrɛtᵊnə/ RET-(ə-)nə, pl. retinae, /ˈrɛtiniː/; from Latin rēte, meaning "net") is the third and inner coat of the eye which is a light-sensitive layer of tissue.

Madarosis is a condition that results in the loss of eyelashes, sometimes eyebrows.

The vitreous body is the clear gel that fills the space between the lens and the retina of the eyeball of humans and other vertebrates.

The extraocular muscles are the six muscles that control movement of the eye (there are four in bovines) and one muscle that controls eyelid elevation (levator palpebrae).

The Lens placode is a thickened portion of ectoderm which serves as the precursor to the lens.

Vitreomacular adhesion (VMA) is a human medical condition where the vitreous gel (or simply vitreous) of the human eye adheres to the retina in an abnormally strong manner.

The frontal eye fields (FEF) are a region located in the frontal cortex, more specifically in Brodmann area 8 or BA8, of the primate brain.

Visual space is the perceptual space housing the visual world being experienced by an aware observer; it is the subjective counterpart of the space of physical objects before an observer's eyes.

Night vision is the ability to see in low light conditions.

A Galactosemic cataract is cataract which is associated with the consequences of galactosemia.

A limbal ring is a dark ring around the iris of the eye.

An odd-eyed cat is a cat with one blue eye and one eye either green, yellow, or brown.

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 (or ophthalmic cup), consisting of two strata of cells.

The optic vesicles 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.

Stereoscopic acuity, also stereoacuity, is the smallest detectable depth difference that can be seen in binocular vision.

The third eye (also known as the inner eye) is a mystical and esoteric concept referring to a speculative invisible eye which provides perception beyond ordinary sight.

The retinohypothalamic tract (RHT) is a photic neural input pathway involved in the circadian rhythms of mammals.

The term congenital cataract refers to a lens opacity present at birth.