Ocular Anatomy Final

Front 1

if the cornea and sclera are removed from the eye...what is the remain visual structure

Back 1

uveal tract

Front 2

what are the largest capillaries in the body? where is it located?

Back 2

choriocapillaris
1. complete matting against retina
2. only capillaries in the choroid
3. densest in the MACULA

Front 3

innervation of the choriodcapillaris? how does it resist collapsing?

Back 3

NOT INNERVATED

resist collapse from high IOP by maintain a HIGH PRESSURE

Front 4

where is the pars plicata? what does it contain?

Back 4

1. 2mm long area at he anterior end of ciliary body
2. THICK
3. VASCULAR
4. contains bulk of the ciliary muscle

Front 5

what is the largest smooth muscle in the eye? where is it? what does it do?

Back 5

1. ciliary muscle
2. attached to the scleral spur
3. controls refractive properties of the crystalline lens by contracting and relaxing the zonules to change the shape of the lens

Front 6

what is the fornix? where is it?

Back 6

1. circular cul-de-sac formed by bending of the conjunctiva from lid to eyeball
2. between orbital and bulbar conjuctiva
3. thick and loose with folds

Front 7

what are the subdivisions of the fornix

Back 7

1. superior: connected by fascial expansion of SR and levator
2. inferior: connected to fascial expansions of IR and IO
3. lateral: extend deeply to behind globe equator
4. medial: NOT PRESENT

Front 8

what are the divisions of the bulbar conjunctiva

Back 8

limbal
sclera

Front 9

how does corneal innervation enter the eye? how many branches does it give off?

Back 9

1. penetrate sclera above the ciliary body and travel to the anterior eye
2. 70-80 branches, penetrate limbus...UNMYELINATED

Front 10

what are the PLEXUSES of CORNEAL INNERVATION

Back 10

1. stromal plexus:
anterior/middle has nerve trunks and nerve endings
posterior in the descemet's endothelium has no nervous tissue
2. subepithelial plexus: in bowman's membrane that run parallel to the corneal surface
3. epithelial plexus: in epithelium and reach surface cells as bare nerve endings

Front 11

thicknesses of the...superior, inferior, lateral, medial...FORNIX

Back 11

superior: 14-15mm
inferior: 10-12mm
lateral: 5-8mm
medial: barely present

Front 12

what is a motor end plate

Back 12

contact made by the terminal branches of the axons with the muscle

Front 13

what happens at the motor end plate? where is it on the muscle?

Back 13

1.myelin sheath of the axon ends, ramifies into small end branches (lay on the surface of the muscle)
2.presynaptic structure (self explanatory)
3. middle 1/3 of the belly of the muscle

Front 14

what is singly innervated fibers

Back 14

1.muscle fibers receiving input from motor end plates
2.one end plate per muscle fiber

Front 15

what is unique about orbital singly innervated fibers

Back 15

UNENCAPSULATED spiral nerve endings

Front 16

what is "en grappe endings"

Back 16

MULTIPLY INNERVATED FIBERS
1. multiple axon terminals are small round, "grape-like" swellings at the end of the axonal process
2. they are found all along the muscle fibers

UNIQUE nerve endings to extraocular muscles and not seen in skeletal muscle but are very similar to nerve endings in smooth muscles

Front 17

difference between singly and multiply innervated fibers

Back 17

CONTRACTILE PROPERTIES
1. single:
twitch fibers
rapid contraction (all or none contractions)
2. multiple:
tonic fibers
graded contractions

Front 18

where does the MEDIAL RECTUS insert

Back 18

horizontal meridian
5.5mm from limbus
closest to cornea, covered by caruncle

Front 19

where does the LATERAL RECTUS insert

Back 19

inserted laterally
horizontal meridian
6.9mm from limbus

Front 20

where does the SUPERIOR RECTUS insert

Back 20

inserts superiorly
vertical meridian
7.7mm from limbus

goes over SO to become inserted farther away from corneal margin than any other rectus muscle

Front 21

where does the INFERIOR RECTUS insert

Back 21

inserts inferiorly
vertical meridian
6.5mm from limbus

Front 22

where does the INFERIOR OBLIQUE insert

Back 22

the posterior, lateral and lower quadrant of the globe
at level of macula

Front 23

where does the SUPERIOR OBLIQUE insert

Back 23

the posterior, lateral and upper
fan shaped, concave forward and oblique

Front 24

from what fibers does the oculomotor regulatory centers receives sensory information

Back 24

muscle spindles
golgi tendon organs
myotendious cylinders (specialized sensory receptors for global multiply innervated fibers)

Front 25

medial rectus innervation? where is the junction?

Back 25

1. inferior division (CN3)
2. lateral surface (middle and posterior third)

Front 26

lateral rectus innervation? where is the junction?

Back 26

1. CN6
2. medial aspect (just behind middle)

Front 27

superior rectus innervation? where is the junction?

Back 27

1. superior division (CN3)
2. under surface of muscle (middle and posterior thirds)

Front 28

inferior rectus innervation? where is the junction?

Back 28

1. inferior division (CN3)
2. upper aspect (middle and posterior thirds)

Front 29

superior oblique innervation? where is the junction?

Back 29

1. CN4
2. upper surface near lateral border

Front 30

inferior oblique innervation? where is the junction?

Back 30

1. inferior division (CN3)
2. crosses above the posterior border to enter the muscle on its upper surface at about the middle of the muscle

Front 31

what are the different portions of the orbicularis oculi

Back 31

1. orbital: around orbital margin on lower forehead, eyebrows, temple and cheek
2. palpebral: in lids
3. ciliary: muscle of Riolan (@ eyelid margin)
4. muscle of horner

Front 32

orbicularis oculi muscle...origin and insertion

Back 32

1. orginate from the medial palpebral ligament and the neighboring bone, pass across the lids in series of half eclipse interlock outside the lateral canthus in lateral palpebral raphe
2. insert to skin through pathway and laterally to form ridge lateral palpebral raphe or lateral palpebral ligament
3. striate, voluntary muscle
4. closest striate muscle to skin in body

Front 33

muscle of Muller...function

Back 33

1. upper lid: levator raise upper lid
superior tarsal muscle
orgin: from levator muscle
insertion: upper border of tarsus

2. lower lid and inferior rectus has weak depression effect on lower lid
Inferior tarsal muscle
origin: lower rectus muscle

Front 34

from anterior to posterior...what are the layers of the iris

Back 34

1. anterior border layer
2. stroma
3. anterior epithelium
4. posterior epithelium

Front 35

pigmentation in iris

Back 35

determined by melanocytes in the stroma and anterior border layer

the more melanocytes the darker the eye...blue eyes have little or no melanocytes

Front 36

lacrimal gland of Wolfring:
what type of gland
location and amount
what does it secrete
function

Back 36

1. conjunctival glands
2. anterior border of tarsus or between extremities of tarsal glands, 2-5 upper and 1-2 lower
3. secrete tear fluid
4. everyday secretion

Front 37

lacrimal gland of krause:
size compared to wolfring
location and amount
secretion and function

Back 37

1. smaller but more numerous than wolfring
2. 20-40 upper, 6-8 lower
3. in fornicial connective tissue
4. everday secretion of tears

Front 38

what are the three layers of the tear film from outer to inner

Back 38

1. LIPID LAYER by tarsal gland (Meibomian), slightly sebaceous glands of Zeis and sweat glands of Moll
2. THICK AQUEOUS LAYER secreted by lacrimal glands (Krause and Wolfring)
3. THIN MUCIN LAYER secreted by Goblet cells of conjunctiva and from lacrimal glands

Front 39

how are the zonules change with age

Back 39

1. infant:
fibers fine and not grouped
2. elderly:
thinner, fewer and more fragile fibers
fibers grouped and aggregate towards anterior and posterior.
equatorial fibers disappeared or migrated anteriorly as the lens grown in thickness

Front 40

what is the capsule

Back 40

1. acellular basement membrane
2. COMPLETELY envelops the lens
3. THINNEST at the POSTERIOR pole and EQUATOR
4. THICKEST just anterior and posterior to the equator

Front 41

what does the lateral trunk of the muscular branch supply?
medial trunk?
what branches off these arteries?

Back 41

1. lateral: levator, SR, LR, SO
2. medial: MR, IR, IO
3. anterior ciliary arteries: 2 arteries to SR, MR, and IR...ONLY ONE in LR

Front 42

what is the largest vein the in orbit?
where does it form?

Back 42

1. superior ophthalmic vein
2. form in upper & medial corner of orbital margin by union of supra-orbital and angular vein

Front 43

Superior Ophthalmic Vein
what does it collect?
where does it empty?

Back 43

1. collect:
anterior and posterior ethmoid vein
muscular veins (superior and medial muscle)
lacrimal vein
two vortex veins

2. enters cavernous sinus

Front 44

what fissure separates the posterior portion of the lateral wall and the floor? what forms this fissure?

Back 44

inferior orbital fissure

maxilla, sphenoid, palatine bone

Front 45

what goes through the inferior orbital fissure

Back 45

infra-orbital artery
branch of inferior opthalmic vein
branch of the CN V2
branch from ptergopalatine ganglion

Front 46

what is the infra orbital groove

Back 46

a shallow depression moving centrally across the floor form the IOF to the infra-orbital canal, which transmits the infra-orbital vessels and nerves

Front 47

what bones makes up the MEDIAL WALL of the orbit

Back 47

1. maxilla: forms frontal process
2. ethmoid:orbital plate form main central part
3. lacrimal: anteriorly and slightly inferiorly
4. sphenoid: forms small part of the posterior portion of wall

THINNEST WALL

Front 48

what occurs in the outer plexiform layer

Back 48

1. connections between the axons of the rods and cones with the dendrites of bipolar cells
2. processes of the horizontal cells, fibers of Muller

cones have pedicles synapse
rods have spherules synpase
pedicles are larger than spherules (both invaginated)

Front 49

what does the INNER NUCLEAR LAYER consist of

Back 49

1. capillaries of the central retina vessels
2. horizontal cell nuclei
3. amacrine cell nuclei
4. Muller fibers nuclei
5. bipolar cell nuclei

Front 50

what does the INNER PLEXIFORM LAYER consist of

Back 50

1. connection between axons of bipolar cells and the dendrites of ganglion cells
2. amacrine cell (distal portion)
3. Muller fibers
4. branches of retinal vessels

Front 51

what does the lateral trunk of the muscular branch supply?
medial trunk?
what branches off these arteries?

Back 51

1. lateral: levator, SR, LR, SO
2. medial: MR, IR, IO
3. anterior ciliary arteries: 2 arteries to SR, MR, and IR...ONLY ONE in LR

Front 52

what is the largest vein the in orbit?
where does it form?

Back 52

1. superior ophthalmic vein
2. form in upper & medial corner of orbital margin by union of supra-orbital and angular vein

Front 53

Superior Ophthalmic Vein
what does it collect?
where does it empty?

Back 53

1. collect:
anterior and posterior ethmoid vein
muscular veins (superior and medial muscle)
lacrimal vein
two vortex veins

2. enters cavernous sinus

Front 54

what fissure separates the posterior portion of the lateral wall and the floor? what forms this fissure?

Back 54

inferior orbital fissure

maxilla, sphenoid, palatine bone

Front 55

what goes through the inferior orbital fissure

Back 55

infra-orbital artery
branch of inferior opthalmic vein
branch of the CN V2
branch from ptergopalatine ganglion

Front 56

what is the infra orbital groove

Back 56

a shallow depression moving centrally across the floor from the IOF to the infra-orbital canal, which transmits the infra-orbital vessels and nerves

Front 57

what bones makes up the MEDIAL WALL of the orbit

Back 57

1. maxilla: forms frontal process
2. ethmoid:orbital plate form main central part
3. lacrimal: anteriorly and slightly inferiorly
4. sphenoid: forms small part of the posterior portion of wall

THINNEST WALL

Front 58

what occurs in the outer plexiform layer

Back 58

1. connections between the axons of the rods and cones with the dendrites of bipolar cells
2. processes of the horizontal cells, fibers of Muller

cones have pedicles synapse
rods have spherules synpase
pedicles are larger than spherules (both invaginated)

Front 59

what does the INNER NUCLEAR LAYER consist of

Back 59

1. capillaries of the central retina vessels
2. horizontal cell nuclei
3. amacrine cell nuclei
4. Muller fibers nuclei
5. bipolar cell nuclei

Front 60

what does the INNER PLEXIFORM LAYER consist of

Back 60

1. connection between axons of bipolar cells and the dendrites of ganglion cells
2. amacrine cell (distal portion)
3. Muller fibers
4. branches of retinal vessels

Front 61

what is unique about the retina in terms of circulation

Back 61

1. highest oxygen consumption per unit weight of any tissue in body
2. two separate circulatory systems

Front 62

what are the two circulatory systems of the retina

Back 62

1. outer 1/3: choroidal circulation (high flow, variable rate)
2. inner 2/3: retinal circulation (low flow, constant rate, high rate of oxygen extraction)

*no vasculature between the inner nuclear layer and choriocapillaris

Front 63

from exterior to interior...what is the relationship between sclera and adj. tissue

Back 63

1. conjunctiva
2. tenon's capsule
3. episclera
4. stroma
5. lamina fusca
6. suprachoroidal space

Front 64

where is the vitreous base

Back 64

along the peripheral retina at the ora serrata and the pars plana of the ciliary body

attachment so firm that it is difficult to separate in desection

Front 65

major aqueous drainage?

Back 65

1. trabecular meshwork
2. canal of schlemm

and then either
3. collector channels
4. deep scleral plexus
5. mid scleral plexus
6. episceral plexus

or
3. aqueous veins (Ascher)
4. episcleral plexus

Front 66

minor aqueous drainage?

Back 66

1. (5-35% )through connective tissue spaces surrounding the ciliary muscle bundles
2. suprachoroidal space absorbed into anterior ciliary vein and vortex veins

Front 67

from T1-T3 how does the eyes dilate (mydriasis)

Back 67

1. T1-T3
2. ventral root
3. SCG
4. internal carotid plexus
5. ophthalmic division
6. nasociliary nerve
7. long ciliary nerve
8. iris dilator
9. MYDRIASIS

Front 68

horners syndrome...symptoms? cause?

Back 68

sympathetic disruption
symptoms:
1. miosis: usual tone for dilator muscle is gone
2. anisocoria: normal eye has larger pupil (more pronounce in dim light)
3. ptosis
4. facial anhidrosis (absence of sweat secretion)

Front 69

what are the motor and sensory components of the CN3

Back 69

1. motor: superior (LPS, SR) and inferior (MR, IR, IO)
2. sensory: proprioceptive fibers from muscle spindles

Front 70

what are the sympathetic and parasympathetic components of the CN3

Back 70

1. sym: in superior division and superior tarsal muscle
2. para: from edginer-westphal nucleus, iris sphincter and ciliary muscle

Front 71

in the optic tract...where is macular, superior fibers and inferior fibers located?

Back 71

1. superior fibers: medial side (both ipsilateral ST and contralateral SN)
2. inferior fibers: lateral side (both ipsilateral IT and contralateral IN)
3. macular fibers located in middle

med-S mid-M lat-I

Front 72

on day 27-28 what happens to the optic vesicle

Back 72

1. distal face of optic vesicle (called RETINAL DISK) reaches surface of ectoderm separated by mesenchymal cells
2. disk-shaped thickening of the neural ectoderm and will become neural retina

Front 73

what is the lens placode

Back 73

1. thickening of the surface ectoderm
2. adjacent to the retinal disk
3. 27th day

Front 74

what happens in the first of the three waves in the 7th week

Back 74

1. mesenchyme pass over the rim of the optic cup
2. between surface ectoderm and lens to form CORNEAL ENDOTHELIUM and TRABECULAR ENDOTHELIUM
3. neural crest cells will form CORNEAL ENDOTHELIUM

Front 75

what happens in the second of the three waves in the 7th week

Back 75

1. cells migrate between primitive corneal endothelium and the lens vesicle to form PUPILLARY MEMBRANE (separate anterior and posterior chamber)
2. neural crest cells of the pupillary membrane will differentiate into fibroblast and melanocytes of the anterior border layer and stroma of iris

Front 76

what happens in the last of the three waves in the 7th week

Back 76

1. cells migrate between primitive corneal epithelium and the primitive corneal endothelium
2. first fibroblast (primary corneal stroma) and then keratocytes and collagen (secondary corneal stroma)

Front 77

what does SURFACE ECTODERM form

Back 77

1. corneal epithelium
2. conjunctiva epithelium
3. lacrimal gland
4. crystalline lens
5. eyelid structures (epithelium, cilia, mebomian, Zeis and Moll)
6. epithelium lining the nasolacrimal sys.

Front 78

what does NEUROECTODERM form

Back 78

1. CN3
2. CN2
3. retina
4. neuroglia
5. epithelium of ciliary body
6. epithelium of iris, including sphincter and dilator

Front 79

what does NEURAL CREST form

Back 79

1. cornea stroma (bowman's layer)
2. corneal endothelium (descemet membrane)
3. sclera
4. uveal pigment cells and connective tissue
5. limbus
6. ciliary body and iris (connective tissue)
7. muscle of ciliary body

Front 80

what does MESODERM form

Back 80

1. orbital bones
2. extraocular muscles
3. blood vessels

Front 81

in which direction does the choroidocapillaris form?
when does it first form?
then what forms?

Back 81

1. posterior pole then differentiate peripherally
2. around 2 months
3. short posterior ciliary arteries (Haller's and Sattlers layer)
4. the layers of the large and medium vessels are there by the 5th month

Front 82

what happens to the long posterior ciliary arteries in development of the choroid

Back 82

1. the long posterior ciliary arteries bypass the developing choroid and contribute to circulation in the anterior aspect of eye
2. initially tunica vasculosa lentis
annular vessels
major arterial circle
intramuscular arterial circle