Orbit and Cavernous Sinus

Question 1

complete ptosis

Answer 1

destruction of the Oculomotor (III) n. or one of its branches to LPS

Question 2

slight ptosis

Answer 2

horner’s syndrome is loss of postganglionic sympathetic fibers from the cervical ganglion
leads to loss of innervation of the tarsal mm

Question 3

parasympathetic inn to lacrimal gland

Answer 3

PRE - superior salviatory nucleus to facial, greater superficial petrosal, and vidan n to sphenoplatine ganglion
POST - sphenopalantine ganglion to maxillary, zygomatic, and lacrimal n to lacrimal gland

Question 4

sympathetic inn to lacrimal gland

Answer 4

POST - superior cervical ganglion to internal carotid plexus to deep petrosal, greater superficial petrosal and Vidian n. through the sphenopalatine ganglion to the maxillary, zygmatic, and lacrimal n. to the lacrimal gland

Question 5

traumatic optic neuropathy

Answer 5

intracanilicular portion of optic n can loose blood supply from ophthalmic a after an orbital fracture

Question 6

blow out fracture

Answer 6

damage of the floor of the orbit
cause herniation of certain orbital structures into the maxillary sinus
(periobita, inferior oblique and inferior rectus m, orbital fat pad)

Question 7

Le Forte Type I

Answer 7

transverse fractures of the maxillae just above the alveolar processes

Question 8

Le Forte Type II

Answer 8

pyramidal-shaped fractures of the maxillae involving part of the medial margin of one orbit

Question 9

Le Forte Type III

Answer 9

extensive transverse fractures of the face involving many facial bones and both orbits (panda bear)
face has been separated from the base of the skull

Question 10

levator palpebrae superioris (LPS)

Answer 10

inn: superior division of III
paralysis: complete ptosis

Question 11

superior rectus (SR)

Answer 11

inn: superior division of III
paralysis: inability to ABduct and elevate the affected eye

Question 12

medial rectus (MR)

Answer 12

inn: inferior division of III
paralysis: inability to ADduct the affected eye

Question 13

inferior rectus (IR)

Answer 13

inn: inferior division of III
paralysis: inability to ABduct and depress the affected eye

Question 14

inferior oblique (IO)

Answer 14

inn: inferior division of III
paralysis: inability to ADduct and elevate the affected eye

Question 15

superior oblique (SO)

Answer 15

inn: IV
paralysis: inability to ADduct and depress the affected eye

Question 16

lateral rectus (LR)

Answer 16

inn: VI
paralysis: inability to ABduct the affected eye
increased intracranial pressure may compress VI leading to paralysis of LR

Question 17

direct and consensual corneal reflexes

Answer 17

IN BY 5 OUT BY 7 
stimulus: touching the cornea 
R: nacked n endings in cornea 
Afferent: nasociliary n
Sensory nucleus: descending nucleus of V 
Motor nucleus: facial nucleus 
Efferent fibers: facial n
Effector: obicularis oculi m 
Response: blinking

Question 18

central retinal a

Answer 18

infero-medial to the optic n and constitutes main supply to the retina

Question 19

sphincter pupillae m

Answer 19

when contracted decrease the diameter of the pupil

inn by POST parasympathetic axons from ciliary ganglion

Question 20

dilator pupillae m

Answer 20

when contracted increase the diameter of the pupil

inn by POST sympathetic branch from the ciliary ganglion

Question 21

direct light reflex

Answer 21

light in one eye leads to pupillary constriction of stimulated eye
mediated at the level of the brainstem via PARAsypmathetics

Question 22

consensual light reflex

Answer 22

light in one eye leads to pupillary constriction of contralateral eye
same as direct light reflex
involved the POSTERIOR COMMISSURE

Question 23

pupillary dilation response

Answer 23

decrease amount of light leads to bilateral reflex dilation of the pupils
SYMPATHETIC response mediated through the brainstem and upper spinal cord

Question 24

horner’s syndrome

Answer 24

leads to ipsilateral pupillary constriction, slight ptosis, and anhydrosis, blushing of the face

Question 25

accommodation

Answer 25

view objects in the near field of vision (cerebral cortex and oculomotor n)
involves convergence of vision, pupillary constriction, and thickening of the lens

Question 26

convergence of gaze

Answer 26

oculomotor nucleus

bilateral contraction of the medial recti mm

Question 27

pupillary constriction

Answer 27

Edinger Westphal nucleus to ciliary ganglion

due to contraction of sphincter pupillae m. mediated by PARAsympathetic component of III

Question 28

thickening of the lens

Answer 28

Edinger Westphal nucleus to ciliary ganglion
due to relaxation of the ciliary zonule fibers by ciliary mm leading to rounding of lens to focus on near objects
PARAsympathetic component of III

Question 29

Argyll-Robertson pupil

Answer 29

result of syphilis infection
pupils are unreactive to light but constrict during accommodation
due to destruction of pretectum

Question 30

Holems-Adie pupil

Answer 30

due to a lesion of ciliary ganglion
initially the tonic pupil does not appear to react to convergence but if convergence is maintained the pupil will slowly constrict

Question 31

hyphema

Answer 31

arterial circle of iris
presence of blood in the anterior chamber of the eyeball due to trauma and rupture of the great arterial circle of the iris
SERIOUS medical condition

Question 32

subconjunctival hemorrhage

Answer 32

deep pericorneal plexus

due to rupture of deep pericorneal plexus. bleeding is restricted to the subconjunctival tissue or bulbar fascia

Question 33

conjunctivitis

Answer 33

superficial pericorneal plexus
brick red inflammation or irritation of the conjunctiva
when touched the redness does not fade and vessels are movable