Eye Flashcards
What color is the optic disc?
White/yellow
What is the nerve supply to the eyeball?
Branches of the nasocillary nerve of the ophthalmic division of the trigeminal
Sympathetic from cavernous plexus
Parasympathetic fibers form ciliary ganglion
What modified sebaceous gland secretes an oily substance that covers tears and reduced evaporation of them?
Tarsal glands
What is the colored part of the eye?
Iris
What structure of the eye does the neural crest mesenchyme give rise to?
Fibrous coats (sclera)
What germ layer gives rise to the lens?
Surface ectoderm
Lens gets harder with age making near vision harder. What’s the name for this>
Presbyopia
There are many tiny ________ in the _______ that allow structures to pass through (within the eye)
Openings, sclera
What is the points where the optic nerve attaches to the eyeball?
Optic disc
What arteries in the eye dont have an accompanying venous supply?
Short ciliary arteries (6-12)
Where do the 6-8 anterior ciliary arteries arch?
Over (3-4) and under (3-4) the eyeball
What maintains the shape if the pressure inside eye increases?
Sclera
One long ____ _____ artery on each side (medial and lateral) of the eyeball and run between the sclera and choroid
Posterior ciliary A.
What is the white part of the eye called?
Sclera
What does increasing the convexity of the lens do?
Allows us to see near vision
What does the external plexiform layer contain?
Rods and cones synapsing with bipolar cells
What nerve does the central retinal artery travel with?
Optic N
The cornea consists of ____ layers. What are they from anterior to posterior?
5
- Corneal epithelium
- Anterior limiting Lamina
- Substantia propria
- Posterior limiting Lamina
- Endothelium
What two structures of the eye does the neuroectoderm give rise to?
Retina
Pigmented structures
What does the lens separate?
Anterior segment from posterior segment
What are cataracts?
Lens becomes less transparent
___-___, _____ _____ arteries enter the eyeball on the posterior surface forming a ring around the optic N
6-12 short ciliary arteries
The fovea centralis is in the middle of what structure?
Macula lutea
What has fibers that are arranges circumferentially that constrict the pupil?
Sphincter pupillae
The cornea is convex/concave to the anterior?
Convex
What does the dark pigment of the choroid (first layer of the vascular tunic) help with?
Pigment limits passage of lights through sclera to retina and retina to sclera
(Passage from structure anterior to it and to its strong attachment)
Is the lens vascular or avascular?
Avascular
What are the functions of the ciliary body?
Suspend the lens, produce GAGs in the anterior segment of the eye and produce GAGs of the vitreous body
What is the darker area of the eye in the center of the fundus?
Macula lutea
What do the long ciliary N supply?
Sensory for ciliary body, iris and cornea
What is the first layer of the cornea and what is it continuous with?
Corneal epithelium
Conjunctiva
(Recall the sclera is lined with conjunctiva anteriorly)
What enter the eyeball at the optic disc?
Major blood vessels
What colors does the iris Range from?
Blue to dark brown
Within the vitreous body there’s a hyaloid canal which in the fetus connected what? What did it contain?
Optic nerve and posterior aspect of the lens. It contained the fetal hyaloid A.
No functional purpose in adults
What does the nerve fiber layer contain?
Retinal ganglion cell axons
NOT myelinated
What is in the middle of the macula lutea?
Fovea centralis
What are the four refractory components of the eyeball?
Cornea
Aqueous humor
Lens
Vitreous body
What are the ten layers of the retina?
- Pigmented layer/cementing layer
- (photosensitive area) Rods/cones
- External limiting membrane
- Outer nuclear layer
- Outer plexiform layer
- Inner nuclear layer
- Inner plexiform layer
- Ganglion cell layer
- Nerve fiber layer
- Internal limiting membrane
What do the short ciliary N supply?
Sensory to the eyeball
What is the second layer of the vascular tunic?
Ciliary body
What two structures of the eye does the surface ectoderm give rise to?
Lens
Cornea
What does the inner nuclear layer contain?
Cell bodies of bipolar cells
What is special about the optic disc?
NO photoreceptors
What does the internal limiting membrane separate?
Retina from the vitreous body
Retina outside/ vitreous body inside
What are the three parts of the middle tunic of the eye, the vascular tunic?
Choroid
Ciliary body
Iris
What gives rise to the retina?
Neuroectoderm
What is the outermost layer of the eye?
Fibrous tunic
What muscle is found within the ciliary body?
Ciliary muscle
The lacrimal sac is found in a ______ between the _____ _____ and the ______. It is the most superior part of the __________ _____
Groove between the lacrimal bone and maxilla
Nasolacrimal duct
What does the nervous tunic/retina contact?
Choroid externally and vitreous body internally
What does the vitreous body fill?
Posterior segment
What does the iris divide?
The anterior segment into anterior and posterior chambers
What layers contain cell bodies?
Outer nuclear layer
Inner nuclear layer
Ganglion cell layer
What muscle will cause the pupil to become larger when it contracts?
Dilator pupillae
Anteriorly, the sclera transitions into the _______ at the _______
Cornea
Limbus
What does the ganglion cell layer contain?
Ganglion cells
Increasing the convexity/concavity of the lens allows for near vision?
Convexity
Lens is biconvex
_________ sympathetic fibers from the ______ _____ pass through the _______ _____ and reach the _____ and _____ _____ muscles of the eye
Postganglionic
Cavernous plexus
Ciliary ganglion
Ciliary and dilator pupillae muscles
What attach to the sclera?
Extraocular muscles
What type of fibers is the sphincter pupillae innervated by?
Parasympathetic
What germ layer gives rise to the cornea?
Surface ectoderm
What type of fibers innervate the dilator pupillae?
Sympathetic
What is the ciliary body continuous with anterior and posterior?
Anterior with iris
Posterior with choroid
Tarsal glands are located in ____ _____ and are _____ _____ glands that secrete an ____ substance that _____ tears upon blinking
Each eyelid
Modified sebaceous
Oily
Cover
Lacrimal ducts are found in each eyelid ____ and ____ to the eyeball. they drain tears into the _____ _____
Below and medial
Lacrimal sac
Where does the nasolacrimal duct drain tears to?
Inferior nasal meatus
What muscles do the sympathetic fibers from the cavernous plexus supply within the eye?
Dilator pupillae and ciliaris (convex- near vision)
What does the lacrimal apparatus consist of?
Lacrimal gland, duct and sacs
What is the pathway the aqueous humor takes after it is secreted by the ciliary bodies?
Secreted into posterior chamber, pass through pupil into anterior chamber, travels laterally and leaves through scleral venous sinus
What is the area of clearest vision in the eye?
Macula lutea
What is the only blood supply to the retina?
Central retinal A
What is the function of the sclera?
Maintains shape if pressure inside eye increases
Anteriorly the sclera transitions into the cornea at the limbus and is lined with ______
Conjunctiva
What produces some GAGs of the vitreous body?
Ciliary body
______ parasympathetic fibers from the ____ _____ follow a similar path to the ______ and ____ ____ muscles
Postganglionic
Ciliary ganglion
Ciliaris and sphincter pupillae muscles
How is the choroid attached to the sclera?
Choroid is loosely attached to the sclera EXCEPT where the optic nerve penetrates it.
Choroid is firmly attached to the sclera where the optic nerve penetrates it.
What is the clear, transparent part of the fibrous tunic?
Cornea
What is the function of the tarsal glands covering tears in an oily coat upon blinking?
Reduces evaporation of tears
What is a clear fluid secreted by the ciliary processes on the posterior aspect of the ciliary body?
Aqueous humor
What photoreceptors are found within the macula lutea?
Cones
The _____ _____ artery travels via the optic N and spreads out into an extensive network.
Central retinal artery
What does the inner plexiform layer contain
Bipolar cells synapsing with ganglion cells
What are the two retinal structures visible upon funduscopic exam?
Optic disc
Macula lutea
What is the fourth layer of the cornea?
Posterior limiting lamina
Posteriorly, the sclera is continuous with a ______ ______ that covers CN __?
Fibrous sheath
CN II
Glaucoma results from increased pressure where?
Anterior segment (anterior/posterior chamber)
How many short ciliary arteries of the eye are there?
6-12
__-__ _____ ____ arteries arch over or under the eyeball
6-8 anterior ciliary arteries
Cornea is the anterior/posterior part of the outermost fibrous tunic?
Anterior
All arteries to the eyeball are branches of what artery?
Opthalamic
What is presbyopia?
Lens gets harder with age—harder to see close
Contraction of what muscle allows the lens to become more convex and allow near vision?
Ciliary muscle
What is the most anterior, PRIMARY refractory structure of the eye?
Cornea
What two muscles do the parasympathetic fibers for the eye supply?
Ciliaris and sphincter pupillae
What is the third layer of the cornea? And what is significant about it?
Substantia propria
Is is the largest part of the cornea
What are the blood vessels of the choroid (first layer of the vascular tunic) primarily supplied by? And what affect may they have?
Autonomic, vasomotor fibers
Cooling effect
6-12 short ciliary arteries enter the eye on the posterior surface and from what where?
A ring around the optic nerve
The long posterior ciliary A in the eye runs between what two structures?
Sclera and choroid
Describe the pigmentation of the choroid (first layer of vascular tunic)?
Darkly pigmented
What suspends the lens?
The ciliary body
Is the first layer of the vascular tunic, choroid, thin or thick and does it have a good or poor blood supply?
Thin, good blood supply
What results from increase pressure within the anterior segment (anterior and posterior chamber) of the eye?
Glaucoma
What produces aqueous fluid found in the anterior segment of the eye?
Ciliary body
What germ layer gives rise to the pigmented structures?
Neuroectoderm
Embryologically speaking the eye is derived from which germ layer?
Ectoderm
The nasolacrimal duct drains tears from the ____ ____ into the _____ _____ _____
Lacrimal sac into the inferior nasal meatus
What is the result of contraction of the ciliary muscle?
Allows the lens to become more convex, allowing near vision
What is the fifth layer of the cornea? And where does it cover?
Endothelium
Inside surface of the cornea and lines the iridocorneal layer
What two things make up the outermost fibrous tunic of the eye?
Sclera, cornea
What are the branches of the nasociliary N of the ophthalmic division of the trigeminal supply the eye?
Long ciliary N
Short ciliary N
What two muscles are found within the iris and what do they do?
Sphincter pupillae
Dilator pupillae
Control the size of the pupil
The aqueous humor is secreted into the ______ ______, passes through the _____ into the ______ _____ and then travels laterally, leaving the eye through the _____ ______ ______
Posterior chamber (part of the anterior segment)
Through pupil
Anterior chamber
Scleral venous sinus
What is an outgrowth of the diencephalon, so therefore it can be considered a specialized portion of the brain? **
Nervous tunic/retina
Openings in the sclera allow what structures to pass through?
Blood vessels and neurons
What is it called when the lens becomes less transparent?
Cataracts
____ ____ vein travels alongside the central retinal A (only supply to retina)
Central retinal
What part of the outermost fibrous tunic of the eye is thick, dense, firm and opaque?
Sclera (neural crest mesenchyme derived)
How many coats/tunics make up the eye? And what are they?
3
Fibrous, vascular, nervous/retina
Where is aqueous humor secreted?
The posterior chamber
(Part of the anterior segement-posterior to iris)
Iris segments anterior segment to anterior/posterior chamber
Photoreceptors synapse with ____ ______ layer cells (bipolar cells) that relay information to the ____ _____ cells (multipolar cells) that carry information to the _____ ____ _____ that form the optic radiation and synapse in ____ _____ _____ of the occipital lobe
Inner nuclear
Ganglionic layer
Lateral geniculate body
Brodmann area 17
_____ _____ veins travel accompany anterior ciliary arteries(6-8)
Anterior ciliary
The lacrimal glands are located _______ to the eyeball and secrete _______ that are carried to the surface of the eye by _____ ______
Superolaterally
Tears
Excretory ducts
What germ layer gives rise to the fibrous coats (sclera)?
Neural crest mesenchyme
What does the outer nuclear layer contain?
Rod and cone cell bodies
______ ____ ____ veins travel with the long posterior ciliary arteries (Bowen sclera/choroid)
Posterior ciliary Veins
What is the second layer of the cornea?
Anterior limiting Lamina
