orbit and cavernous sinus CIS Flashcards Preview

Neuroscience I test 2 > orbit and cavernous sinus CIS > Flashcards

Flashcards in orbit and cavernous sinus CIS Deck (28)
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1
Q

lacrimal apparatus, route of tears

A

lacrimal canaliculi–>lacrimal sac–>nasolacrimal duct–>inferior nasal meatus (why tears cum out of nose)

2
Q

oculumotor nerve palsy gaze

A

downward and outward gaze, dilated pupil

3
Q

loss of innervation to what muscle causes complete ptosis in a patient
-what nerve

A

levator palpebre superioris

oculomotor nerve

4
Q

mydriasis seen in oculomotor nerve palsy is caused by disruption of what neural pathway?

A

parasympathetic fibers to the sphincter pupillae m

5
Q

signs of oculomotor nerve palsy

A

down and out eye
complete ptosis
pupil dilation

6
Q

which area in the brain is responsible for consensual light reflex

A

posterior commisure

7
Q

direct light reflex pathway

A

retina–>optic nerve–>optic tract–>brachiam of superior colliculus–>superior colliculus–>pretectum–>edinger-westphal nucleus–>occulomotor nerve–>ciliary ganglion–>pupillary constrictor muscles

8
Q

horner’s syndrome triad of signs

A

slight ptosis, miosis and anhydrosis

9
Q

causes of horner’s syndrome

A

mass effect (pancoast tumor)
aortic or carotid artery aneurysm
idiopathic or congenital

10
Q

decreased light and dilating pupil pathway

A

retina–>optic nerve–>superior colliculus–>pretectum–>reticular formation–>lateral reticulospinal tract–>preganglionic symp neruons–>superior cervical ganglion–>pupillary dilator muscles

11
Q

argyll robertson pupil

A

pupil constricts when object brought towards eye but not when light shined on it
(normal accommodation abnormal light relfex)
-associated with syphllyis (Garrett)

12
Q

triad of accommodation

A

convergence of gaze
pupillary constriction
thickening of lens

13
Q

holmes adie pupil

A

tonically slow reacting pupil to light
normal response to accommodatino
caused by infection but not syphillis (not garrett)

14
Q

hyphema

A

blood pooling in anterior chamber of eye due to rupture of arterial circle of iris

15
Q

subconjunctival hemorrhage

vessel involved and description

A

deep pericorneal plexus

-bleeding restricted to subconjunctival tissue or bulbar fascia

16
Q

conjunctivitis vessel involved and description

A

superficial pericorneal plexus

-red inflammation or irritation of conjunctiva

17
Q

le fort 1 fracture

A
  • horizontal maxillary fracture
  • separates teeth from upper face
  • fracture line passes through alveolar ridge, lateral nose and inferior wall of maxillary sinus
18
Q

le fort 2 fracture

A

pyramidal fracture with teeth at the pyramid base
can involve orbit but only 1 side
fracture passes through alveolar ridge, lateral walls of maxillary sinus and inferior orbital rim and nasal bones

19
Q

le fort 3 fracture

A

both orbits involved

fracture line passes through nasofrontal suture orbital wall and zygomatic arch

20
Q

branches of nasociliary nerves

A

posterior ethmoid
anterior ethmoid
long ciliary nerves

21
Q

where do the superior and inferior ophthalmic veins drain

A

into the cavernous sinus

22
Q

ophthalmic artery gives off what arteries

A
supraorbital
posterior ethmoidal 
anterior ethmoidal 
lacrimal
short ciliary
23
Q

clinical findings with blow out fracture

A
  • enophthalmos: due to increased orbital volume
  • diplopia: due to extra ocular muscle entrament
  • orbital emphysema: especially when frature in adjacent paranasal sinus
  • malar region numbness: due to injury to inferior orbital nerve
24
Q

where is the central retinal artery located

A

right in middle of optic nerve

25
Q

presentation of central retinal artery lesion

A

one eye goes black

abrupt and painless

26
Q

what exits the superior orbital fissure

A

V1
cranial nerves III,IV,VI
opthalamic vein

27
Q

branches of V1

A
Nasociliary nerve
Frontal nerve
    -supraorbital
    -supratrochlear
Lacrimal nerve
28
Q

corneal reflex

A
touch cornea 
receptor nerve endings
afferent: nasociliary n, especially long ciliary
sensory nucleus: descending nucleus of V
motor nucleus: facial nucleus
efferent: facial nerve
effector: orbicularis oculi muscle