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368 terms

Combo with Ch 2 Anatomy and Physiology of the Eye and 7 others

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Floaters
Particles of cellular debris that float in the vitreous fluid and cast shadows on the retina
Vitreous
The clear jelly-like substance that fills the space behind the lens (also called the vitreous body)
Stye
A red, sore lump nearly outer edge of the eyelid caused by an inflamed lash follicle (also called external hordeolum)
Blepharitis
inflammation of the eyelids characterized by redness, swelling, and crusted lid margins
Binocular vision
the ability to focus the two eyes in a coordinated manner in order to see one image
Corneal Epithelium
The outermost Layer of the cornea providing defense against infection and injury. This layer also contains nerve endings but does not contain blood vessels.
Chalazion
Chronic nontender inflammation of a meibomian gland, usually the result of a blocked duct; commonly presents as a swelling on the upper or lower eyelid
Inferior Oblique
Rolls eye up and out (laterally)
Optic Radiation
The nerve cels that transmit visual information from the lateral geniculate body to the visual cortex
Optic Disc
Region at the back of the eye where the optic nerve meets the retina. It is the blind spot of the eye because it contains only nerve fibers, no rods or cones, and is thus insensitive to light.
Orbit
the bony cavity in the skull containing the globe, extra-ocular muscles, blood vessels, and nerves. All of which are cushioned by layers of fat.
Cataract
Clouding of the natural lens of the eye. (opacified)
Opacification
The process of the lens becoming cloudy or opaque. Happens to people over 65.
Optic nerve
The nerve that carries neural impulses from the eye to the brain.
Physiologic blind spot
sightless "hole" in the normal visual field corresponding to the optic disc where there are no photoreceptors
Tear Film
Three layered-coating that covers the front surface of the globe:
Outer Lipid Layer- Fatty layer secreted by meibomian glands which prevents evaporation of underlying aqueous humor
Middle Aqueous Layer- Secreted by lacrimal glands, mostly aqueous,provides Oxygen and nutrients
Inner Mucous Layer- lies over surface of conjunctiva and cornea; secreted by goblet cells of conjunctiva and is important in stability of tear film, and the spread of tear film over cornea
Conjunctivitis
inflammation (swelling of the blood vessels) of the conjuctiva; caused by irritation, allergy, or bacterial infection. ( pink eye),
Subconjunctival Hemorrhage
Rupture of a conjunctival blood vessel that allows blood to flow under the tissue and produces a bright-red flat area on the conjunctiva
Retina
the light-sensitive inner lining of the back of the eyeball; contains receptor cells (rods/cones)
Ectropion
The turning out (eversion) of the lower eyelid caused by muscle weakness.
Cones
Cone-shaped visual receptor cells; located in retina; works best in bright light; responsible for viewing color; greatest density in the fovea
Ptosis
Drooping of and inability to raise the upper eyelid; caused be the levator muscle's inability to function
Anterior Chamber
Area behind the cornea and in front of the lens and iris. It contains aqueous humor.
Sphincter muscle
The muscle that encircles the pupil and makes the pupil smaller in response to bright light
Physiology
Processes and functions of an organism
Glaucoma
Increased pressure in the eyeball due to obstruction of the outflow of aqueous humor; causes damage to the optic nerve
Tarsal Plate
Dense, plate-like frame work with in the middle layer of each eyelid that gives the eyelids their firmness and shape. (also called tarsus)
Entropion
Inward turning of the rim of the eyelid
Corneal abrasion
An injury, such as a scratch or irritation, to the outer layers of the cornea
Internal Hordeolum
AKA internal stye; occurs when a meiboian gland becomes infected or inflamed.
Exophthalmos
Protrusion of one or both eyeballs, often because of thyroid dysfunction or a tumor behind the eyeball Also called Proptosis
Fusion
The combining of images from the two eyes to form a single visual image
Anatomy
The structure of an organism
Eyelid
Movable, protective fold that opens and closes, covering the eye. Contains 3 layers:
Outer layer- Skin
Middle layer- Tarsal plate, Orbicularis Oculi, Levator Palperae Superioris
Inner layer-Conjunctiva
Foreign Body Sensation
FBS. A feeling of eye irritation or grittiness.
Strabismus
A disorder in which the eyes point in different directions or are not aligned correctly because the eye muscles are unable to focus together
Globe
The eyeball
Vitreous
Jelly-like substance filling the inner chamber between the lens and retina that gives bulk to the eye
Structures of the eye
Cornea,Sclera,Anterior Chamber,Uveal Tract, Crystaline Lens,Vitreous, Retina,Visual Pathways
Trichiasis
Misdirected eyelashes that rub on the conjunctiva or cornea
Rods
Rod-shaped retinal receptors that detect black, white, and gray; necessary for peripheral and twilight vision, when cones don't respond
Conjunctiva
Mucous membrane that lines the eyelids and outer surface of the eyeball, except the cornea.
Corneal Ulcer
Lesion on the cornea left after an infection of or injury to the corneal epithelium
Anterior Chamber Angle
The junction of the cornea and the iris, from which aqueous humor leaves the eye (also called filtration angle)
Cornea
Clear membrane at the front of the globe covering the iris, pupil, and anterior chamber. Responsible for 60% of the eyes focusing power. Contains 5 layer:
Corneal Epithelium, Bowman's Membrane, Corneal Stroma, Descemet's Membrane, and Corneal Endothelium
Descemets Membrane
Basement membrane that lies between the corneal stroma and the endothelial layer of cornea
Corneal Endothelium
Inner layer of cornea, maintains corneal hydration and secrets Descemet's Membrane. Will not regenerate.
Bowmans Membrane
A layer of the cornea, located between the corneal epithelium and the corneal stroma, acts as an anchor for the corneal epithelium. Resistant to trauma/bacterial invasion, will not regenerate
Corneal Stroma
90% of corneal mass, contributes rigidity to the cornea.
Medial Rectus
Moves eye inward, Adduction.
Inferior Rectus
Moves eye down
Superior Rectus
Moves eye up
Lateral Rectus
Moves eye out, Abduction
Superior Oblique
Moves eye down and in
Ciliary Process
Epithelia tissue folds on the inner surface of the ciliary body that secretes aqueous humor
Fornix
Juncture between palpebral conjunctiva and the bulbar conjunctiva, where the eyelid and the globe meet. (Also called Cul-de-sac)
Palpebral Conjunctiva
Membrane that lines the eyelids
Choroid
A highly vascular membrane in the eye between the retina and the sclera in the uveal tract. Provides nourishment to the retina
Prognosis
A prediction of the course of a disease
Photoreceptor
A light sensitive cell
Adnexa
Tissues and structures surrounding the eye; includes:
Orbit
Extraocular Muscles
Eyelids
Lacrimal Apparatus
Meibomian Gland
A gland that secretes the oily part of the tear film that lubricates the outer surface of the globe: located on the inner margin of the eyelid.
Crystalline Lens
Forty percent of the optical focusing system, immediately behind the iris, aka Lens
Trabecular Meshwork
Sponge-like structure that filter the aqueous humor from the anterior chamber and controls it's rate of flow to the Canal of Schlem.
Posterior Segment
Rear portion of the eye; includes the vitreous body and the retina
Anterior Segment
Front of the eye; from the front of the cornea to the back of the lens
Limbus
Junction between the sclera and the cornea
Optic Chiasm
Point behind the eyes in the brain where the two optic nerves merge and the axon fibers from the nasal retina of each eye cross to the opposite side
Aqueous Humor
Clear, transparent fluid that fills the anterior chamber
Sclera
Tough, fibrous, white outer coat extending from the cornea to the optic nerve
Nasolacrimal Duct
A duct that carries tears from the lacrimal sac to the nasal cavity
Lacrimal Sac
Holds tears that pass from the lacrimal canaliculi and empty in to the nasolacrimal duct
Accommodation
The process by which the eye's lens changes shape to focus near or far objects on the retina
Lateral Canthus
The point where the upper and lower eyelids meet at the temporal side
Cilia
Eyelashes
Canaliculus
Tubes (upper and lower) through which tears pass into the Lacrimal Sac
Punctum
Tiny opening on the upper and lower lid margins near the nose through which tears pass
Dacryocystitis
Inflammation of the lacrimal sac causing obstruction of the tube draining tears into the nose
Orbicularis Oculi
Circular muscle, in the middle layer of eye lid, that closes the eye as in winking, blinking
Lateral Geniculate Bodies
Part of the brain where optic fibers synapse to the optic radiations and transmit visual impulses
Axons
Long-fiber like portion of the ganglion cells that course over the surface of the retina and converge at the optic disc
Ganglion Cells
Type of retinal cells that accepts electric (nerve) impulses from the bipolar cells and send the impulses via axons through the optic disc to the brain
Canal of Schlemm
A structure which drains the aqueous humor from the anterior chamber after it has flowed through the trabecular meshwork
Lacrimal Gland
The gland that produces the watery substance making up the middle layer of the tear film; located in the lateral part of the upper lid
Bipolar Cells
A type of retinal cells that accepts electric (nerve) impulses from the photoreceptors and passes them to the ganglion cells
Zonule
A transparent fiber that supports the lens by attaching to the ciliary body
Synapse
The connection between nerves, where electric (nerve) impulses are transmitted
Palpebral Fissure
The almond shaped opening between the upper and lower eyelids
Medial Canthus
The point where the upper and lower eyelids meet on the nasal side
Visual Pathway
The route that is taken by light-generated nerve impulses after they leave the eye; also called the Retrobulbar visual pathway
Iris
The colored circle of tissue that controls the amount of light entering the eye by enlarging or reducing the size of it's aperture, the pupil.
Macula
Specialized area of the retina close to the center of the back of the eye that provides detailed central vision
Fovea
Center of the macula
Pupil
The opening in the center of the iris that dilates admitting more light, and constricts admitting less light
Presbyopia
Progressive loss of accommodative ability of the lens, due to the natural process of aging
Pigment epithelium
Outer layer of the retina; lies against the choroid
Ciliary Body
A band-like structure of muscle and secretory tissue that extends from the edge of the iris and encircles the inside of the sclera
Ciliary Muscle
Smooth muscle portion of the ciliary body, which contracts to assist in near-vision capability
Lacrimal Apparatus
A structure of the eye that produce tears and the ducts that drain excess fluid from the front of the eyes into the nose. Including:tear film, lacrimal gland, upper and lower punctum, upper and lower canaliculus, lacrimal sac, and nasolacrimal duct
The eye as an optical System
Cornea, Iris, pupil, crystalline lens, vitreous, retina, and optic nerve
Uveal Tract
The pigmented layers of the eye including: Iris, ciliary body, and choroid, that contain the majority of the blood vessel supply (also called Uvea)
Dilator Muscle
The iris muscle that dilate the pupil in reduced light conditions; fibers from this muscle stretch from the pupil to the boundaries of the iris.
Visual Cortex
Area of the brain responsible for the initial conscious registration of visual information; the designation of electric (nerve) impulses from the retina
Bulbar conjunctiva
The tissue lining the globe up to the edge of the cornea
Optic Tract
The part of the brain between the optic chiasm and the lateral geniculate body
Levator Palpebrae
The muscle attached to the tarsal plate in the middle layer of the upper and lower eyelids, that raises the eyelid when it contracts
Amblyopia
-amblys "dulled" ops "eye"
-reduction in vision due to abnormal visual experience in early childhood
-most commonly caused by strabismus & asymmetric refractive error
Strabismus
Misaligned vision. Fovea may not be focused on the same object leading to diplopia.
Lateral rectus
Abducts, turn out
Medial rectus
Adducts, turns in
Blowout fracture
Fraxture in the floor of the orbit.
Orbit
Holds the globe. 
Lens
immediately behind the iris, 40% of focusing power.
Adnexa
Structures that protect & support globe.
Cornea
Clear membrane ot front of globe, 60% of focusing power
Iris
Controls amount of light that enters the eye
Superior rectus
Turns up
Inferior rectus
Turns down
Optic nerve
Carries electrical messages from retina to brain
Retina
inner lining of the back of the eye consisting of light sensitive cells which convert images to electrical impulses
Superior oblique
Intorsion, down & in
Inferior oblique
Extorsion, up & out
Pupil
opening in iris that allows light to enter eye
The ocular adnexa
tissues that surround the eye and protext and preserve the nomal functioning of the eyes. eyedids, conjunctiva the lacrimal apparatus, the orbit, and the extraocular muscles.
eyelids and conjunctiva
tissue that protects the outer portion of the eye from injury, excludes light, lubricates th efront surface of the eye. Composed of outer layers of skin, and inner layer of palpebral conjunctiva and the layer of fiberous tissue and muscle between upper and lower lids
palpebral fissure
elliptical opening btween upper and lower lids. 15 mm normal opening
medial cantus
inner junciton of lids.
lateral canthus
outer junction of lids.
plica semilunaris
the medial canthus contains folds of fleshy tissue. this is the deeper one.
caruncle
more visible fold
puncta
small openings to the drainage system on medial edge of lids
cilia
on anterior lid margin are hair follicles for the lashes. to sweep airborne particles away from the eye during a blink.
gray line
it divides the inner and outer portion of the lid margin.
meibomian glands
oil secreting glands.
tarsal plate
fiberous layer of lids. it gives teh lid its firmness
orbicularis oculi
a circular muscle that on contraction result in eye closure
Levator palpebrea superioris muscle
it attaches to the tarsal platee
oculomotor nerve
is the 3rd cranial nerve that controls a group of muscles
conjuctiva
is hte transulant mucous membrane that lines the iner surface of the lids.
palpebral conjunctiva
portion of conjunctiva on the lids
bulbar conjunctiva
conjunctiva on the surface of the eye.
Limbus
where bulbar conjuctivs ends and cornea begins.
fornix culdesac
junction of bulbar conjunctiva and palpebral conj. hordeolum stye acute infalation of a lash follicle that forms reddened lump near the lid margin.
blepharitis
diffuse inflamation of lid margin. over growth of bacteria.
Ecotropian
turnin out of the lid
entropian
inward turning of the lashes
ptosis
loss of function of levator muscle.
conjunctivitis
inflamation of conjunctiva pink eye
sub conjunctivial
hemorrhage blood vessel ruptures under the conjuctiva
pingueculum
yellowish mass on the bulbar conjuctiva just nasal or temporal to the limbus, usually from the sunlight. specially people who work in the wind
ptergium
continued irritation of pingueculum may result in this. A fleshy wedge of bulbar conjunctiva that grows from the canthus toward the cornea.
Floaters
Particles of cellular debris that float in the vitreous fluid and cast shadows on the retina
Vitreous
The clear jelly-like substance that fills the space behind the lens (also called the vitreous body)
Stye
A red, sore lump nearly outer edge of the eyelid caused by an inflamed lash follicle (also called external hordeolum)
Blepharitis
inflammation of the eyelids characterized by redness, swelling, and crusted lid margins
Binocular vision
the ability to focus the two eyes in a coordinated manner in order to see one image
Corneal Epithelium
The outermost Layer of the cornea providing defense against infection and injury. This layer also contains nerve endings but does not contain blood vessels.
Chalazion
Chronic nontender inflammation of a meibomian gland, usually the result of a blocked duct; commonly presents as a swelling on the upper or lower eyelid
Inferior Oblique
Rolls eye up and out (laterally)
Optic Radiation
The nerve cels that transmit visual information from the lateral geniculate body to the visual cortex
Optic Disc
Region at the back of the eye where the optic nerve meets the retina. It is the blind spot of the eye because it contains only nerve fibers, no rods or cones, and is thus insensitive to light.
Orbit
the bony cavity in the skull containing the globe, extra-ocular muscles, blood vessels, and nerves. All of which are cushioned by layers of fat.
Cataract
Clouding of the natural lens of the eye. (opacified)
Opacification
The process of the lens becoming cloudy or opaque. Happens to people over 65.
Optic nerve
The nerve that carries neural impulses from the eye to the brain.
Physiologic blind spot
sightless "hole" in the normal visual field corresponding to the optic disc where there are no photoreceptors
Tear Film
Three layered-coating that covers the front surface of the globe:
Outer Lipid Layer- Fatty layer secreted by meibomian glands which prevents evaporation of underlying aqueous humor
Middle Aqueous Layer- Secreted by lacrimal glands, mostly aqueous,provides Oxygen and nutrients
Inner Mucous Layer- lies over surface of conjunctiva and cornea; secreted by goblet cells of conjunctiva and is important in stability of tear film, and the spread of tear film over cornea
Conjunctivitis
inflammation (swelling of the blood vessels) of the conjuctiva; caused by irritation, allergy, or bacterial infection. ( pink eye),
Subconjunctival Hemorrhage
Rupture of a conjunctival blood vessel that allows blood to flow under the tissue and produces a bright-red flat area on the conjunctiva
Retina
the light-sensitive inner lining of the back of the eyeball; contains receptor cells (rods/cones)
Ectropion
The turning out (eversion) of the lower eyelid caused by muscle weakness.
Cones
Cone-shaped visual receptor cells; located in retina; works best in bright light; responsible for viewing color; greatest density in the fovea
Ptosis
Drooping of and inability to raise the upper eyelid; caused be the levator muscle's inability to function
Anterior Chamber
Area behind the cornea and in front of the lens and iris. It contains aqueous humor.
Sphincter muscle
The muscle that encircles the pupil and makes the pupil smaller in response to bright light
Physiology
Processes and functions of an organism
Glaucoma
Increased pressure in the eyeball due to obstruction of the outflow of aqueous humor; causes damage to the optic nerve
Tarsal Plate
Dense, plate-like frame work with in the middle layer of each eyelid that gives the eyelids their firmness and shape. (also called tarsus)
Entropion
Inward turning of the rim of the eyelid
Corneal abrasion
An injury, such as a scratch or irritation, to the outer layers of the cornea
Internal Hordeolum
AKA internal stye; occurs when a meiboian gland becomes infected or inflamed.
Exophthalmos
Protrusion of one or both eyeballs, often because of thyroid dysfunction or a tumor behind the eyeball Also called Proptosis
Fusion
The combining of images from the two eyes to form a single visual image
Anatomy
The structure of an organism
Eyelid
Movable, protective fold that opens and closes, covering the eye. Contains 3 layers:
Outer layer- Skin
Middle layer- Tarsal plate, Orbicularis Oculi, Levator Palperae Superioris
Inner layer-Conjunctiva
Foreign Body Sensation
FBS. A feeling of eye irritation or grittiness.
Strabismus
A disorder in which the eyes point in different directions or are not aligned correctly because the eye muscles are unable to focus together
Globe
The eyeball
Vitreous
Jelly-like substance filling the inner chamber between the lens and retina that gives bulk to the eye
Structures of the eye
Cornea,Sclera,Anterior Chamber,Uveal Tract, Crystaline Lens,Vitreous, Retina,Visual Pathways
Trichiasis
Misdirected eyelashes that rub on the conjunctiva or cornea
Rods
Rod-shaped retinal receptors that detect black, white, and gray; necessary for peripheral and twilight vision, when cones don't respond
Conjunctiva
Mucous membrane that lines the eyelids and outer surface of the eyeball, except the cornea.
Corneal Ulcer
Lesion on the cornea left after an infection of or injury to the corneal epithelium
Anterior Chamber Angle
The junction of the cornea and the iris, from which aqueous humor leaves the eye (also called filtration angle)
Cornea
Clear membrane at the front of the globe covering the iris, pupil, and anterior chamber. Responsible for 60% of the eyes focusing power. Contains 5 layer:
Corneal Epithelium, Bowman's Membrane, Corneal Stroma, Descemet's Membrane, and Corneal Endothelium
Descemets Membrane
Basement membrane that lies between the corneal stroma and the endothelial layer of cornea
Corneal Endothelium
Inner layer of cornea, maintains corneal hydration and secrets Descemet's Membrane. Will not regenerate.
Bowmans Membrane
A layer of the cornea, located between the corneal epithelium and the corneal stroma, acts as an anchor for the corneal epithelium. Resistant to trauma/bacterial invasion, will not regenerate
Corneal Stroma
90% of corneal mass, contributes rigidity to the cornea.
Medial Rectus
Moves eye inward, Adduction.
Inferior Rectus
Moves eye down
Superior Rectus
Moves eye up
Lateral Rectus
Moves eye out, Abduction
Superior Oblique
Moves eye down and in
Ciliary Process
Epithelia tissue folds on the inner surface of the ciliary body that secretes aqueous humor
Fornix
Juncture between palpebral conjunctiva and the bulbar conjunctiva, where the eyelid and the globe meet. (Also called Cul-de-sac)
Palpebral Conjunctiva
Membrane that lines the eyelids
Choroid
A highly vascular membrane in the eye between the retina and the sclera in the uveal tract. Provides nourishment to the retina
Prognosis
A prediction of the course of a disease
Photoreceptor
A light sensitive cell
Adnexa
Tissues and structures surrounding the eye; includes:
Orbit
Extraocular Muscles
Eyelids
Lacrimal Apparatus
Meibomian Gland
A gland that secretes the oily part of the tear film that lubricates the outer surface of the globe: located on the inner margin of the eyelid.
Crystalline Lens
Forty percent of the optical focusing system, immediately behind the iris, aka Lens
Trabecular Meshwork
Sponge-like structure that filter the aqueous humor from the anterior chamber and controls it's rate of flow to the Canal of Schlem.
Posterior Segment
Rear portion of the eye; includes the vitreous body and the retina
Anterior Segment
Front of the eye; from the front of the cornea to the back of the lens
Limbus
Junction between the sclera and the cornea
Optic Chiasm
Point behind the eyes in the brain where the two optic nerves merge and the axon fibers from the nasal retina of each eye cross to the opposite side
Aqueous Humor
Clear, transparent fluid that fills the anterior chamber
Sclera
Tough, fibrous, white outer coat extending from the cornea to the optic nerve
Nasolacrimal Duct
A duct that carries tears from the lacrimal sac to the nasal cavity
Lacrimal Sac
Holds tears that pass from the lacrimal canaliculi and empty in to the nasolacrimal duct
Accommodation
The process by which the eye's lens changes shape to focus near or far objects on the retina
Lateral Canthus
The point where the upper and lower eyelids meet at the temporal side
Cilia
Eyelashes
Canaliculus
Tubes (upper and lower) through which tears pass into the Lacrimal Sac
Punctum
Tiny opening on the upper and lower lid margins near the nose through which tears pass
Dacryocystitis
Inflammation of the lacrimal sac causing obstruction of the tube draining tears into the nose
Orbicularis Oculi
Circular muscle, in the middle layer of eye lid, that closes the eye as in winking, blinking
Lateral Geniculate Bodies
Part of the brain where optic fibers synapse to the optic radiations and transmit visual impulses
Axons
Long-fiber like portion of the ganglion cells that course over the surface of the retina and converge at the optic disc
Ganglion Cells
Type of retinal cells that accepts electric (nerve) impulses from the bipolar cells and send the impulses via axons through the optic disc to the brain
Canal of Schlemm
A structure which drains the aqueous humor from the anterior chamber after it has flowed through the trabecular meshwork
Lacrimal Gland
The gland that produces the watery substance making up the middle layer of the tear film; located in the lateral part of the upper lid
Bipolar Cells
A type of retinal cells that accepts electric (nerve) impulses from the photoreceptors and passes them to the ganglion cells
Zonule
A transparent fiber that supports the lens by attaching to the ciliary body
Synapse
The connection between nerves, where electric (nerve) impulses are transmitted
Palpebral Fissure
The almond shaped opening between the upper and lower eyelids
Medial Canthus
The point where the upper and lower eyelids meet on the nasal side
Visual Pathway
The route that is taken by light-generated nerve impulses after they leave the eye; also called the Retrobulbar visual pathway
Iris
The colored circle of tissue that controls the amount of light entering the eye by enlarging or reducing the size of it's aperture, the pupil.
Macula
Specialized area of the retina close to the center of the back of the eye that provides detailed central vision
Fovea
Center of the macula
Pupil
The opening in the center of the iris that dilates admitting more light, and constricts admitting less light
Presbyopia
Progressive loss of accommodative ability of the lens, due to the natural process of aging
Pigment epithelium
Outer layer of the retina; lies against the choroid
Ciliary Body
A band-like structure of muscle and secretory tissue that extends from the edge of the iris and encircles the inside of the sclera
Ciliary Muscle
Smooth muscle portion of the ciliary body, which contracts to assist in near-vision capability
Lacrimal Apparatus
A structure of the eye that produce tears and the ducts that drain excess fluid from the front of the eyes into the nose. Including:tear film, lacrimal gland, upper and lower punctum, upper and lower canaliculus, lacrimal sac, and nasolacrimal duct
The eye as an optical System
Cornea, Iris, pupil, crystalline lens, vitreous, retina, and optic nerve
Uveal Tract
The pigmented layers of the eye including: Iris, ciliary body, and choroid, that contain the majority of the blood vessel supply (also called Uvea)
Dilator Muscle
The iris muscle that dilate the pupil in reduced light conditions; fibers from this muscle stretch from the pupil to the boundaries of the iris.
Visual Cortex
Area of the brain responsible for the initial conscious registration of visual information; the designation of electric (nerve) impulses from the retina
Bulbar conjunctiva
The tissue lining the globe up to the edge of the cornea
Optic Tract
The part of the brain between the optic chiasm and the lateral geniculate body
Levator Palpebrae
The muscle attached to the tarsal plate in the middle layer of the upper and lower eyelids, that raises the eyelid when it contracts
eye lashes
what are the short hairs that project from the border of each eyelid?
eye lashes and eye brows
what two accessory structures protect the eye ball from foreign objects, such as perspiration and dust, and partially shade the eyeball from the sun
foreign objects
the eye lashes and eye brows protect the eyeball from what?
eye lashes and eye brows
what protects the eyeball from perspiration, dust, and partially shade the eyeball from the sun?
sebaceous ciliary glands
what type of glands are located at the base of the hair follicles, and help lubricate the eyeball?
help lubricate the eyeball
the sebaceous ciliary glands help do what for the eye ball?
base of the hair follicles
the sebaceous ciliary glands are located at the base of what?
sebaceous ciliary glands
what type of sebaceous glands are located at the base of the hair follicles, and help lubricate the eyeball?
sty
when the sebaceous ciliary glands are blocked, they become inflamed, this creates what?
when sebaceous ciliary glands are blocked
what causes a sty in the eye?
conjunctivitis
inflammation of the conjuctiva is called what?
bacteria, dust, smoke, or air pollutants
conjunctivitis can be caused by what? Hint: four things
tear
lacrimal means what?
lacrimal
a tear is called what?
lacrimal glands, lacrimal canals, lacrimal sac, and nasolacrimal duct
the lacrimal apparatus consists of what four things
lacrimal apparatus
the lacrimal glands, lacrimal canals, lacrimal sac, and nasolacrimal duct; make up what?
superior and lateral to each eyeball
the lacrimal glands can be found where on each eyeball?
lacrimal glands
which glands are superior and lateral to each eyeball?
lacrimal duct
each lacrimal gland contains 6 to 12 excretory what?
lacrimal glands
lacrimal ducts are contain in what?
lacrimal duct
what delivers a slightly alkaline solution the the anterior surface of the eyeball?
lacrimal fluid of tears
the lacrimal duct delivers a slightly alkaline solution the the anterior surface of the eyeball, this solution can be called what? Hint: two answers
lacrimal fluid
what type of fluid cleans, moistens, and lubricates the surface of the eyeball?
cleans, moistens, and lubricates the surface of the eyeball
the lacrimal fluid does what to the surface of the eyeball? Hint: three things
lacrimal duct
what delivers lacrimal fluid?
lyozyme
lacrimal fluid contains an antibacterial enzyme called what?
antibacterial enzyme
lyozyme is what?
lyozme in lacrimal fluid
what attacks any bacteria that may be on the surface of the eyeball?
medially across the eyeball surface
does the lacrimal fluid move laterally or medially across the eyeball surface?
medially and enters two small openings of the medial canthus
lacrimal fluid moves how across the eyeball surface and enters two small openings of the what?
two small openings
the medial canthus how many openings, that lacrimal fluid enters?
superior and inferior lacrimal puncta
what are the two small openings of medial canthus called?
openings
puncta means what?
nasolacrimal duct
the superior and inferior lacrimal puncta lead to an expanded portion of what duct?
lacrimal sac
nasolacrimal duct are called what?
nasolacrimal duct
lacrimal sac are what kind of duct?
nasolacrimal duct
which duct drains lacrimal fluid into the nasal cavity?
drains lacrimal fluid into the nasal cavity
nasolacrimal duct do what?
superior rectus, inferior rectus, medial rectus, lateral rectus, superior and inferior oblique muscle
what are the six extraocular muscles that control the movements of the eyeball?
superior rectus, inferior rectus, medial rectus, lateral rectus
which of six extraocular muscles are considered straight muscles?
superior and inferior rectus
which of the six extraocular muscles move the eyeball up and down?
medial and lateral rectus
which of the six extraocular muscles move the eyeball side to side?
diagonally on the eyeball
the superior and inferior oblique muscle attach how on the eyeball?
trochlea
the superior oblique muscle has a tendon passing through the what?
superior oblique muscle
which extraocular muscle has a tendon passing through the trochlea?
located on the upper orbit
the trochlea is located on which orbit?
superior oblique muscle
which oblique muscle pulls the eyeball downward?
inferior oblique muscle
which oblique muscle pulls the eyeball upward?
Role of external surface layers
provide protection from trauma and infection
Outer layer of globe
sclera and cornea
conjunctivia
mucous membrane that lines the eyelids and covers the sclera in front
sclera
fibrous outer covering of the eyeball and the white of the eye
prevents stray light from degrading retinal image
Cornea
transparent, anterior part of the eyeball covering the iris, pupil, and anterior chamber that functions to refract (bend) light to focus a visual image
limbus
the border between the cornea and the sclera
corneal layers (5)
Epithelium
Bowman's Membrane
Stroma
Descemet's Membrane
Endothelium
Epithelium
Layer 1
function of barrier and refractive surface
regenerates rapidly, 24 hrs or less
most likely to be injured, does not leave scarring
Bowman's membrane
Consists of randomly oriented collagen fibrils, no regenerative capabilities, it's function is unclear
Stroma
90% of corneal thickness
consists of Lamellae - collagen fibres
Descemet's Membrane
provides rigidity and a barrier to water from AC
Endothelium
Maintains corneal hydration, contributes to corneal transparency, not regenerative
Failure of function leads to corneal edema (Swelling)
Globe
Eyeball and all components it holds
3 main layers of eyeball wall
Sclera, choroid and retina
Adnexa
Eyelids, eyebrows. tear drainage system, orbital walls and orbit contents (accessory structures)
Role of eyelids
protect fron injury, excessive light and to spread tear film over cornea
Orbicularis Oculi
Closes eyelids; used in blinking, winking, and squinting
sphincter muscle
Levator palpebrea superioris
elevate upper eyelid out of line of vision
Muller Muscle
smooth muscle, involuntary muscle of eyelid
Tarsal Plate
a thick fold of connective tissue that gives form and support to the eyelids
grey line
refers to areas along meibomian gland openings, surgical reference point
canthi
corners where eyelids come together. lateral & medial.
Lateral is acute angle and medial is rounded
Caruncle
found in the medial canthus, it is a small fleshy mass containing sebacceous glands
puncta
drainage hole in corner of eyeball for tears; connects upper/lower eyelids to drainage canal; visible at inner canthus of upper/lower lids
epicanthus
a vertical fold of skin on either side of the nose
palpebral fissure
The almond shaped opening between the upper and lower eyelids
lacrimal glands
gland located in the upper outer region above the eyeball that secretes tears
Conjunctival Epithelium
continuous with skin of eyelid and with the cornea; 3-4 layers thick on lower, 2-3 on upper; stratified columnar near lids, squamous near limbus; goblet cells and crypts of Henle
Crypts of Henle
invaginations in conjunctival epithelium where things get stuck
Submucosal Conjunctival Layer
thicker in orbital than in tarsal; loose, vascularized CT; lymphoid and fibrous layers
Lymphoid layer of Submucosal Conj.
immunologically active IgA and has connective tissue components
Fibrous layer of Submucosal Conj.
blood vessels, nerves, collagen, accessory lacrimal glands
Palpebral Conjunctiva
covers inside of eyelids; connected at fornix to KPS and EOMS providing coordination of movement
Bulbar Conjunctiva
covers the sclera, loosely adherent to underlying tissue, more tightly near cornea, merges with Tenon's Capsule
Tenons Capsule
space which the globe moves in; protects the globe, attaches to orbital connective tissue
Fornix
where bulbar and palpebral conj. merge, lateral fornix is deepest, superior and inferior but NO medial
Lympathics
superficial and deep in the submucosa, drain into eyelids
Inn. of Bulbar Conj
long ciliary nerve
Inn. of Superior Palp. Conj
frontal and lacrimal n.
Inn. of Inferior Palp. Conj
lacrimal, infraorbital n.
Functions of Lacrimal System
tear drainage, movement and creation
Punctum
hole where tears drain
Canaliculi
tube coming from punctum; inferior and superior join together
Nasolacrimal Sac
common canaliculus drains
Nasolacrimal Duct
in maxillary bone, where sac drains, ends in inferior meatus
Valve of Hasner
at inferior meatus, keeps stuff from nose from getting into lacrimal system
lacrimal gland
located in fossa of same name, temporal and superior to the eye, sits on LPS and LR; orbital and palpebral divisions, ducts exit thru palpebral lobe
acini
lobes and accessory glands forming an irregular arrangement of secretory cells around the lumen, connected by ducts that drain into fornix
Lipid Layer of tears
waxy esters, cholesterols, FFAs made by Meibomian glands; keeps aqueous from evaporating and lubricates eyelid
Mucous layer
made by goblet cells, adheres tears to corneal surface, absorbed by glycocalyx
Aqueous layer
made by lacrimal gland; contains a lot of organic substance which forms the "crustyness"
Main functions of the Cornea
transmit light into retina and aid in focus 45 D of eye power; protects against infection; maintains pressures and balances of chambers
Cornea Epithelium
outermost layer, has 3 layers, lots of nerves, very sensitive to injury
Surface epithelium
2 layers thick, short, fat, non-keratinized squamous cells with flat nuclei and not many organelles; tight junctions make things go THRU cells instead of between; help tear movement
Wing Cell layer
convex anterior surface, concave posterior; joined by desmosomes, gap junctions and macula occludens
Basal layer
single layer of columnar cells; secrete basement membrane; sight of mitosis for cornea
Bowman's layer
very thing, dense fibrous sheet of collagen fibers in mucoproteins; NO CELLS, does not regenerate
Stroma
90% of cornea, strong, organized into lamellae of collagen fibrils with keratocytes in between layers; also has WBCs, PMNs, macrophages, nerves, ground substance
Ground substance of stroma
fills in spaces, made up of proteins and collagen that bind to water to keep consistent spacing; Keratin Sulfate and Chondroitin
Descemet's Membrane
anterior: collagen; posterior: regenerated thruout life, elastic properties; resistant to trauma but will roll up into anterior chamber if cut
Hassall-Henle Bodies
patho. dome shaped protrusions into anterior chamber coming from descemet's membrane; endothelium thins over them
Corneal Endothelium
basal part is more superior; single layer, maintains water balance by ion pumps; sits near ant. chamber; mosaic;
Nerves of the Cornea
long posterior ciliary and short posterior ciliary, a lot of free nerve endings in epi.