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Flashcards in Orbit Deck (119):
1

The _____coverint the eyelid is very thin and continuous with the palpebral conjunctiva

skin

2

sparse, loose conective tissue that rarely contains fat in the eye

subucatneous tissue

3

ciliary glands are found in what laere of the eyelid

subcutaneous tissue

4

ciliar glands are

mixed sebaceous and modifies sweat glands

5

Zeis glands

sebaceous

6

Moll glands

modified sweat

7

if the sebaceous and modifies sweat glands of the eyelid become infected, what forms

a sty

8

Orbicularis occuli has two portions

palpebral potion and lacrimal portion.
palpebral - integrated with levitator palpebrae superiors
lacrimal - extends from posterior lacrimal crest to the tarsal plates of lids and lacrimal sac, increases the amount of lid contact to the suface of the eyeball

9

levator palpebrae superioris muscle inserts

into palpebral fascia and skin of upper lid

10

levator palpebrae euperioris innervated by

GVE fibers of oculomotor nerve (III)

11

destruction of the oculomotor nerve or one of its branches to levitator palpebrae superiorisresults in

paralysis of this muscle and COMPLETE ptosis

This is ocular nerve palsy

12

Ocular nerve palsy

complete ptosis, external strabismus, pupillary dilation

13

tarsal muscle of Muller inserts on

tarsal plate of the upper lid

14

tarsal muscle innervated by

postganglioinc sympathetic fibers

15

tarsal muscle affected in what syndrome

horner;s syndrome

16

cartilagineous plate tied in with the orbital septum

tarsus

17

Horner's syndrome involves

paralysis of the tarsal muscle, concomitant SLIGHT ptosis an dmiosis.
enophthalaus and anhidrosis and blushing

18

the retina is an invagination of

diencephalon

19

othe ___ formas a firewall between deep and superficial contents of the orbit

orbital septeum

20

why is the orbital septum important

because the orbit is very closely related to the brain

21

when we suffer traumatic facial injure what do we care about repairing first

want to line up the teeth and the orbit

22

Palpebral fascia is composed of

tarsus and orbital septum

23

What do the tarsal glands secrete, and why is ti important

an oily secretion which helps to resist the overflow of tears at the palpebral margin

24

tarsus

comprised of two dense fibrous connective tissue plates in the upper and lower margins of the lids.
both are attached to the medial and lateral palpebral ligaments, and are semilunar shaped in order to conform the curvature of the eyeball

25

what happens if you throw off the margin of the eyelids

like when you mess up your windshield wipers. lids no longer uniformly moving across the surface of the eye

26

Continuous with periosteum at the superior and inferior orbital margins, attached to tarsal plates,

orbital septum

27

superior palpebral fascia is pierced by

levator palpebrae superioris m

28

Conjunctiva

thin membrane that lines the back of the eyelids (palpebral)and front of the eyeball (bulbar)

29

palpebral conjunctiva

is opaque and highly vascular membrane. covers posterior surface of lids,

30

bulbar conjunctiva is

transparent membrane loosely attached to the eyeball.

31

semilunar fold

crescent shaped membranous fold formed by the bulbar conjunctiva t the MEDIAL can thus. forms the lateral border of the triangularly shaped lacrimal lake at the center of which is the lacrimal carunck

32

why can't swelling of the lid get from upper lid to lower lid on the medial side

because of the orbital septum at the medial side.

33

what gland produces tears to keep the surface of the cornea moist

lacrial gland

34

parasympathetic innervation of lacrimal gland

superior salivatory nucleus--> facial nerve--> freater superficial petrosal nerve and vidian nerve --> sphenopalatine ganglion

post ganglionic parasympathetic fivers course via maxillary, zygomatic and lacrimal nerves

35

Sumpathetic innervation of the lacrimal gland

post ganglionic sympathetic fibers from superior cervical ganglion, --> internal carotid plexus--> deep petrosal nerve, --> fuses with greater superficial petrosal to form vidian nerve--> through sphenopalatine ganglion and distribute to lacrimal gland via maillary zygomatic lacrimal nerve route.

may even reach it in lacrimal plexus in adventitia of lacrimal artery

36

lacrimal canaliculi

small L shaped tube located at the palpebral margins of each led at the medial canthus. The two canaliculi straddle the posterio aspect of the medial palpebral ligament

37

function of lacrimal canaliculi

drain tears from the surface of the eyeball to the superior lateral aspect to the lacrimal sac

38

lacrimal sac

elongated sac receives the lacrimal canaliculi and is continuous inferiorly with nasolacrimal duct

39

nasolacrimal duct courses through

nasolacrimal canal. and opens into inferior meatus 1cm posterior to the anterior edge of the inferior concha (drains into the nasal cavity)

40

Bony orbit comprised of what bones

frontal, zygomatic, maxilla, each are common points of fracture

41

supraorbital margin of orbit

frontal bone
supra orbital notch

42

lateral margin of orbit

zygomatic bone, associated with orbital tubercle, the point or attachment of lateral palpebral ligament

43

infraorbital margin

zygomatic and maxilla bones
infraorbital foramen at midpoint

44

margins are ____ than walls

thicker

45

herniation of orbital contents herniate where

maxillary sinus - here we are concerned with infection

46

fractures of the orbit can compress what structure

the optic nerve

47

Blow out fractures of the floor of the orit

may be due to trauma to the front of the eyeball or a depressed fracture of the zygomatic bone, which is displaced medially
cause herniation of certain orbital structures into maxillary sinus

48

Le Forte Type I

transverse fractures of the maxillae just above alveolar processes

49

Leforte Type II

pyramidal sheped fractures of maxillae usually involving part of the medial margin of one of the orbits

50

LeForte Type III aka

craniofacial dysjunction

51

Le Forte Type III

extensive tranverse fractures of face involving many facial bones and both orbits. basically the face has been separated from th ease of the skull

52

trauma to anterior globe pushes it through

the floor of the orbit

53

Periobita is continuous with

endocranium of middle cranial fossa (endosteal dura)
is the periosteum of the orbit

54

endosteal dura is continusouw with

periosteal fascia, palpebral fascia and periosteum of the orbital rim

55

sheath of the optic nerve is

dura

56

meningeal dura is continuous with

sheet of the optic nerve.

57

periorbita and bulbar fascia are usu fused at optic canal and SOF, separating

the orbital cavity from the middle cranial fossa

58

bulbar sheath or fascia

covrs optic nerve and entire eyeball except cornea

59

Abducens palsy

increaased ICP may compress abducens nerve and result in paralysis of lateral rectus mucle
SUNDOWN GAZE (down and in)

60

paralysis of trochlear nerve

superior oblique
inability to adduct and depress affected eye

61

oculomotor palsy

complete ptosis,
inability to abduct and elevate eye (SR)
inability to adduct affected eye (MR)
inability to abduct and dprese affected eye(IR)
inability to adduct and elevate affected eye (IO)

62

Oculomotor palsy passive sign

external strabisms

63

SO causes eye to look

down and in.

64

positions of the eye where that muscle is maximally active

cardinal signs of gaze

65

V1 Lacrimal nerve fiber type

GSA

66

V1 fontal nerve

GSA terminates as supraorbital and supratrochlear n

67

V1 nasociliary nerve

GSA nerve to eyeball

68

V1 anterior ethmoidal nerve

supplies antero superior nasal cavity and part of the outer nose

69

Corneal Reflex - nerves

in by 5, out by 7

70

Direct and consensual Corneal reflexes
stimulus
receptor
afferent fibers
sensory nucleus
motor nucleus
efferent fibers
effector
response

protective reflex
lightly touching cornea
nakedd nerve endings in cornea
nasociliary nerve, especially long ciliary nerves
descending nucleus of V
facial nucleus
facial nerve
orbicularis oculi muscle
blinking (both direct and consensual

71

primary sensory nerve for the eyeball

nasociliary nerve

72

conjugate gaze

eyes move in parallel

73

the only normal disconjugate gaze

convergence - cortically mediated

74

accommodation

focusing in a near field.
eyes converge and constrict

75

Occulomotor nerve fiber types

GSE to the extra ocular muscles
GVE-P to ciliary muscles of lens and sphincter pupillae muscle of iris

76

ciliary ganglion fiber types

GVE-P
postganglionic sympathetic
GSA

77

Ciliary ganglion located between

lateral rectus and optic nerve

78

Cortically mediated responses that are components of accommodation

pupillary constriction and thickening of the lens

79

pupillary constriction and thickening of the lens are responses of what branch of ans

parasympathetic

80

Paralysis of oculomotor results in

external strabismus
complete ptosis
dilated and unreactive pupils

81

paralysis of trochlear results in

inability to aDduct and depress the affected eye
pt tends to tilt his head away from the affected eye

82

paralysis of abducens nerve results in

inability to aBduct the affected eye
diplopia due to internal strabismus

83

Chief artery of the orbit, usually the first branch of ICA

ophthalmic artery

84

arteries that supply optic nerve, what artery do they arise from

posterior ciliary a, central retinal a
from ophthalmic artery

85

main blood supply to the retina

Central retinal artery

86

terminal branches of arteries in the retina are ______ meaning that _________,
we see these terminal branches where>

end arteries
there is not a lot of anastomotic connections
we see these with our ophthalmoscope

87

tehe central retinal artery supplies the four quadrants of the retina through

upper and lower temporal branches and upper and lower nasal branches.

88

Direct light reflex

elicited by shining a bright light in an eye resulting in ipsilateral pupillary constriction, which is mediated at the level of the brainstem via the parasympathetics

89

Consensual light reflex

shining a bright light in one eye will result in pupillary constriction of the contralateral eye
degree of constriction may be less than that in the ipsilateral eye.

90

Direct and consensual light reflex differ in the fact that

the consensual light reflex pathway has the addition of the posterio r commisure to get the reflex

91

important structrual components of the pupillary light reflex

pretectum and the posterior commisure

92

pathway for direct light reflex

retina-->optic nerve--> optic tract-->brachium of superior colliculuc--> superior colliculus-->pretectum-->edinger westphal nucleus--> oculomotor nerve--> ciliary ganglion--> pupillary constrictor muscle--> ipsilateral pupillary constriction

93

pathway for indirect light reflex

retina--> optic nerve--> optic tract-->brachim of superior colliculus-->superior colliculus--> pretectum--> POSTERIOR COMMISURE--> opposite side edinger westphal nucleus--> opposite oculomotor nerve--> opposite ciliary ganglion--> pupilary constrictor muscles--> contralateral pupilary constrition

94

pupillary dilation response

decrease in amount of light reaching retina results in bilateral reflex diction of the pupils

95

pupillary dilation response mediated through

brainstem and upper spinal cord

96

horner;s sydrome

interruption of the pupillary dilation response. characterized by ipsilateral pupillary constriction, slight ptosis and anhydrous and blushign

97

pupilary dilation response path

decreased light--> retina-->optic nerve-->superior colliculus--> pretectum-->reticular fromation--> lateral reticulospinal tract--> preganglionic sympathetic neruons at T1--> back to head --> superior cervical ganglion--> pupillary dilator muscles

response is pupillary dilation

98

Triad of accomodation

convergence of gaze
pupillary constriction
thickening of the lens

99

Accommodation is a ______ mediated response

cortically mediated
from frontal eye field of frontal lobe and projects to the midbrain

100

is accommodation a reflex

no

101

Accommodation is the only naturally occurring_____gaze

disconjugate

102

Accommodation path

frontal eye field--> corticotectal fibers--> superior colliculus--> edinger westphal and oculomotor nucleus

edinger westphal--> ciliary ganglion --> pupillary constriction and thickening of lens

oculomotor nucleus--> convergence of gaze (dysconjugate gaze)

103

Pretectum is a critcal link

direct light response

104

ILCC at T1 is a critical link

pupillary dilation

105

cortically mediated response

accomodation

106

posterior commissure

consensual light reflex

107

horners syndrom

pupillary dilation

108

convergence of gaze, pupillary constriction, thickening of lens

triad of accommodation

109

in by two out by 3

pupillary response

110

in by 2 out by sympathetic branch of ciliary ganglion from SCG

pupillary dilation

111

corticotectal fibers and edinger wetphal and oculomotor nuclei

accomodation

112

Argyll Robertson pupil aka

prostitutes sign

113

argyll robertson pupil definition

accommodating but unreactive

114

argyll robertson pupil cause

syphilis infection
due to destruction of pretectum (important in light reflex but not in accommodation)

115

the pretectum is important in ______ but not in ______

light reflex, but not in accomodation

116

Holmes Adie pupil aka

tonic adie pupil

117

Holmes Adie pupil definition

benign condition which may be due to lesion of ciliary ganglion
slow constriction on convergence

118

Homes aide pupil and parasympathomimetic drus

parasympathomimetic drugs constrict the tonic pupil - no effect on normal pupil

119

papilledema

Increased ICP restricts venous return from the retina
the concomitant increase in venous pressure results in edema or swelling of the optic disc