Exam 1 Flashcards
1
Q
CN I
A
Name: olfactory n.
Associated opening(s): olfactory foramina in cribiform plate
Type: special sensory
Innervation target: olfactory epithelium
2
Q
CN II
A
Name: optic n.
Associated opening(s): optic canal (sphenoid bone)
Type: special sensory
Innervation target: retina
3
Q
CN III
A
Name: oculomotor n.
Associated opening(s): superior orbital fissure
Type: motor
Innervation target: inferior oblique, medial rectus, inferior rectus, superior rectus mm.
4
Q
CN IV
A
Name: trochlear n.
Associated opening(s): superior orbital fissure
Type: motor
Innervation target: superior oblique m.
5
Q
CN V1
A
Name: Opthalmic branch of trigeminal n.
Associated opening(s): superior orbital fissure, supraorbital foramen (exits)
Type: sensory
Innervation target: skin on upper 1/3 of face
6
Q
CN V2
A
Name: maxillary branch of trigeminal n.
Associated opening(s): foramen rotundum, infraorbital foramen (exits)
Type: sensory
Innervation target: skin on middle 1/3 of face
7
Q
CN V3
A
Name: mandibular branch of trigeminal n.
Associated opening(s): foramen ovale
Type: sensory; motor
Innervation target: skin on lower 1/3 of face, pain from tongue; temporalis, masseter, medial and lateral pterygoid mm.
8
Q
CN VI
A
Name: abducens n.
Associated opening(s): superior orbital fissure
Type: motor
Innervation target: lateral rectus m.
9
Q
CN VII
A
Name: facial n.
Associated opening(s): internal acoustic meatus, stylomastoid foramen (exits)
Type: motor; special sensory
Innervation target: muscles of facial expression; tastebuds on anterior 2/3 of tongue
10
Q
CN VIII
A
Name: vestibulocochlear n.
Associated opening(s): internal acoustic meatus
Type: special sensory
Innervation target: inner ear (cochlea and vestibular apparatus)
11
Q
CN IX
A
Name: Glossopharyngeal n.
Associated opening(s): jugular foramen
Type: special sensory; motor
Innervation target: tastebuds on posterior 1/3 of tongue; muscles of pharynx
12
Q
CN X
A
Name: vagus n.
Associated opening(s): jugular foramen
Type: sensory; special sensory; motor
Innervation target: skin across throat and external acoustic meatus; taste and gag reflex; smooth muscles of pharynx and gut
13
Q
CN XI
A
Name: accessory n.
Associated opening(s): jugular foramen, foramen magnum (exits)
Type: motor
Innervation target: trapezius, SCM, muscles of pharynx
14
Q
CN XII
A
Name: hypoglossal n.
Associated opening(s): hypoglossal canal
Type: motor
Innervation target: muscles of tongue
15
Q
Occipitofrontalis
A
Innervations: facial n.
Branch: posterior auricular nerve
Action(s): raises eyebrows
16
Q
Platysma
A
Innervations: facial n.
Branch: cervical
Action(s): depress mandible, tense skin of inferior face and neck
17
Q
Buccinator
A
Innervations: facial n.
Branch: buccal
Action(s): helps keep food in cheek
18
Q
Orbicularis oculi
A
Innervations: facial n.
Branch: zygomatic
Action(s): wink, squeeze eyes shut
19
Q
Levator labii superioris
A
Innervations: facial n.
Branch: buccal
Action(s): lift upper lip
20
Q
Zygomaticus major and minor
A
Innervations: facial n.
Branch: zygomatic
Action(s): Elvis lip
21
Q
Orbicularis oris
A
Innervations: facial n.
Branch: buccal
Action(s): purse lips
22
Q
Depressor anguli oris
A
Innervations: facial n.
Branch: buccal
Action(s): frown
23
Q
Levator anguli oris
A
Innervations: facial n.
Branch: buccal
Action(s): smile
24
Q
Depressor labii inferioris
A
Innervations: facial n.
Branch: buccal
Action(s): depress lower lip
25
Mentalis
Innervations: facial n.
Branch: marginal mandibular
Action(s): pouty face
26
SCM
Innervations: accessory n.
| Action(s): rotation of head to opposite side, flexion
27
Masseter, temporalis, medial and lateral pterygoids
Innervations: Mandibular branch of trigeminal nerve (CN V3)
Actions: muscles of mastication
28
Levator palpebrae superioris
Innervations: oculomotor
Action: lifts eyelid
Clinical testing: eye up
29
Superior rectus
Innervations: oculomotor
Action: eye elevates and adducts (medial/nasal rotation)
Clinical testing: lateral then elevate
30
Superior oblique
Innervations: trochlear
Action: eye depresses and abducts (lateral/temporal rotation)
Clinical testing: have them look medial to align muscle and then look down
31
Medial rectus
Innervations: oculomotor
Action: eye medially rotated
Clinical testing: adduct
32
Lateral rectus
Innervations: abducent
Action: eye laterally rotated
Clinical testing: abduct
33
Inferior rectus
Innervations: oculomotor
Action: eye depresses and adducts (medial/nasal rotation)
Clinical testing: lateral then depress
34
Inferior oblique
Innervations: oculomotor
Action: eye elevates and abducts (lateral/temporal rotation)
Clinical testing: have them look medially to align muscle and then look up
35
CN V motor function
- Muscles of mastication
- Tensor Tympani
- Tensor Veli Palatini
- Mylohyoid
- Anterior belly of digastric
36
CN V sensory function
- Major sensory nerve of face
- Dura mater
- Cornea, conjunctiva
- Anterior 2/3 tongue sensation*
- Teeth
- Buccal mucosa
- External ear and canal
- External part of TM
- Temporal region
- Paranasal sinuses
37
CN V nuclei located in...
Pons
38
Three branches of opthalmic division of CN V
-Nasociliary
-Frontal
-Lacrimal
(terminates as supraorbital / supratrochlear nn.)
39
Maxillary divides into...
- Zygomatic n.
- Infraorbital n. (terminal n. that exits out infraorbital foramen)
- Palatine
- Superior alveolar (anterior, middle, posterior)
40
Manibular divides into...
- Auriculotemporal
- Inferior alveolar
- Lingual
- Buccal
- Mental
41
4 parasympathetic ganglia and their associated nerves
- Ciliary - short ciliary n
- Otic - auriculotemporal n
- Submandibular - lingual n
- Pterygopalatine - palatine n
42
Trigeminal neuralgia
- Disorder of the sensory root of CN V
- Characterized by sudden attacks of excruciating facial pain
- V2 most frequently involved
- Pt. sometimes has aberrant arterial branch lying in close contact to affected nerve
43
Somatic motor innervation of facial n.
- Muscles of facial expression
- Stapedius
- Stylohyoid
- Posterior belly of digastric
44
Visceral motor fibers of facial n. (parasympathetic)
- Chorda tympani nerve
| - Greater petrosal nerve
45
Special sensory (intermediate nerve) of facial n.
Chorda tympani>>lingual nerve (CN V3)
46
Facial nerve motor root path
Internal acoustic meatus>>facial canal (within petrous temporal bone)>>geniculate ganglion>>stylomastoid foramen
47
What nerve does the facial nerve immediately give off after exiting via the stylomastoid foramen?
Posterior auricular nerve
48
5 terminal branches of facial nerve
- Temporal
- Zygomatic
- Buccal
- Marginal mandibular
- Cervical
49
Bell's Palsy
- Paralysis to muscles of facial expression
- May/may not have loss of taste on anterior 2/3 tongue
- May/may not have decreased secretions from lacrimal or submandibular and sublingual salivary glands
- Loss of EFFERENT limb of corneal reflex
50
Chorda tympani nerve
- Carries taste from anterior 2/3 tongue
- Preganglionic parasympathetic fibers to submandibular ganglion>>unites with lingual nerve>>postganglionic parasympathetic fibers to submandibular and sublingual salivary glands
51
Greater petrosal nerve
preganglionic parasympathetic>>pterygopalatine ganglion>>postganglionic parasympathetic fibers>>maxillary n.>>zygomatic n>>lacrimal n>>lacrimal gland (or mucous glands of palate, maxillary sinus, and nasal cavity)
52
Layers of the scalp
```
Skin
Connective tissue
Aponeurosis
Loose (areolar) CT
Periosteum (pericranium)
```
53
Which layer of the dura mater forms folds?
Meningeal dura
54
What do dural venous sinuses carry?
Venous blood and CSF
55
How are dural venous sinuses different from veins?
Only have tunica intima and no valves
56
What are connecting veins between sinuses and scalp?
- Emissary veins - drain scalp through bone and into sinuses
- Bridging veins - drain subarachnoid space
- Cerebral veins - drain brain tissue itself
57
Epidural hematoma
- Usually caused by trauma
- Rupture of middle meningeal artery near pterion common cause
- Bleeding creates an epidural space inside the cranial cavity
- Lens shape puts pressure on brain affects...
- CN III>>dilated pupil
- CN VI>>adducted pupil
- CN II>>bulging of optic cup
58
Subdural hematoma
- Often caused by tearing of bridging veins (due to brain moving around in skull - elderly, babies)
- Within a space that already exists so it can go across the brain surface (can be hard to detect)
59
Choroid plexus
- Found in walls of ventricles
- Supplied by branches of cerebral arteries
- Creates CSF
60
Function of cisterns
CSF pools here so it doesn't drain instantaneously like a sprinkler system, taking high pressure fluid and distributing it timely
61
Circulation of CSF
Right and left ventricles>>interventricular foramen>>3rd ventricle>>cerebral aqueduct>>4th ventricle>>median and lateral apertures OR central canal>>subarachnoid space>>arachnoid villi>>superior sagittal sinus
62
Sternohyoid
Innervation: C1-C3 (ansa cervicalis)
| Action(s): depress hyoid after being elevated during swallowing
63
Omohyoid
Innervation: C1-C3 (ansa cervicalis)
| Action(s): depress, retract, and steady hyoid
64
Sternothyroid
Innervation: C2-C3 (ansa cervicalis)
| Action(s): depress hyoid and larynx
65
Thyrohyoid
Innervation: CN XII
| Action(s): depress hyoid and elevate larynx
66
Digastric
Innervation: A - n. to mylohyoid (inferior alveolar n.)
P - CN VII
Action(s): depress mandible against resistance, elevate and steady hyoid with swallowing and speech
67
Stylohyoid
Innervation: CN VII
| Action(s): elevate and retract hyoid>>elongate floor of mouth
68
Mylohyoid
Innervation: CN V3
| Action(s): elevate hyoid, floor of mouth and tongue when swallowing/talking
69
Cricothyroid
Innervation: external laryngeal n. (CN X)
| Action(s): stretch/tense vocal lig. and increase vocal pitch
70
Levator scapulae
Innervation: dorsal scapular n.
| Action(s): elevate scapula and inferiorly tilt glenoid cavity
71
Anterior scalene
Innervation: C4-6
| Action(s): flex head
72
Middle scalene
Innervation: cervical spinal nerves (anterior rami)
| Action(s): flex neck laterally, elevate 1st rib during inspiration
73
Suboccipital triangle bounded by
Medial - rectus capitis posterior major
Lateral - obliquus capitis superior
Inferior - obliquus capitis inferior
74
Posterior triangle bounded by
Anterior - posterior border of SCM
Posterior - anterior border of trapezius
Inferior - clavicle
75
Anterior triangle bounded by
Anterior - midline of neck
Posterior - anterior border of SCM
Superior - mandible
Inferior - sternum
76
Structures within suboccipital triangle
Suboccipital nerve and vertebral artery
77
Structures within anterior triangle
Common carotid artery, internal jugular vein, thyroid gland and cartilage, hyoid muscles, hyoid bone
78
Structures within posterior triangle
Accessory nerve, lesser occipital nerve, great auricular nerve
79
Geniohyoid
Innervation: hypoglossal n.
Action: assists in opening mandible
80
Hyoglossus
Innervation: hypoglossal n.
Action: depresses tongue
81
Genioglossus
Innervation: hypoglossal n.
Action: protrudes tongue
82
Le Fort I
Horizontal fracture of maxilla, palatine bone, and pterygoid plates of the sphenoid bone; separates inferior maxilla, teeth, and palate from the rest of the face
Affects: maxillary sinus, superior alveolar nerves and arteries, greater and lesser palatine nerves and arteries, incisive artery
83
Le Fort II
Fracture through maxilla and lacrimal bones; may involve zygomatic, ethmoid, nasal, and parts of sphenoid bones
Affects: inferior orbit, lacrimal apparatus, maxillary sinus, infraorbital nerve and artery, nasal septum, superior alveolar nerves and arteries, greater and lesser palatine nerves and arteries, septal and lateral nasal branches of maxillary nerve and sphenopalatine artery
84
Le Fort III
Fracture through greater wing of sphenoid, ethmoid, lacrimal, nasal bones, frontozygomatic region, pterygoid plates of sphenoid, zygomatic bone/arch
Affects: medial and lateral walls of orbit, ethmoid bone/air cells, inferior orbital fissure, zygomatic branches of maxillary nerve, other maxillary nerve branches may be stretched
85
Muscles innervated by vagus
- Superior, middle, inferior pharyngeal constrictor
- Esophagus
- Levator veli palatini
- Salpingopharyngeus
- Palatopharyngeus
86
What muscle is innervated by glossopharyngeal?
Stylopharyngeus
87
Pharynx function
1. Pharynx senses food (CN IX)
2. Soft palate contracts - closes off nasopharynx (CN X and V3)
3. Suprahyoid muscles and epiglottis close off laryngeal opening (C1 and V3)
4. Longitudinal pharyngeal muscles shorten pharynx (CN IX and X) and pharyngeal constrictors (CN X) move bolus inferiorly
88
Scalp infection
loose areolar tissue allows sliding; purulent material can spread infection if reaches scalp
89
Headache
- dural membrane (CN V, all 3 branches) pain receptors
- CN X, CN XII, C2, C3– infratentorial part of dura mater
- Neurovascular headaches (migraine) generate pain through activation of CN V nociceptors in dura
90
Cavernous sinus infection
-trabecular network traps thrombi; facial vv. connect through ophthalmic vv.
o facial vv. are valveless
o infectious thrombus introduced into cavernous sinus will get trapped there
o cranial nerves traveling through sinus can be involved if infected: III, IV, V1, VI
-CN VI first affected>> paralysis of LR m. >>present with affected side eye adducted
91
Cavernous sinus hypertension
-rupture/aneurysm of internal carotid a. (traveling through cavernous sinus) elevates BP w/i sinus >> pressure on nerves (particularly CN VI)
o Ophthalmic vv. also obstructed >> exophthalmos and palpable pulse of globe
92
Fluid spread in deep face
-infection in superficial face can spread rapidly because cutaneous nature of facial muscles means limited attachment to underlying bone >> no barriers to movement of fluid and infection underneath this layer
o Lymph can be moved easily by effleurage (Galbraith’s Technique)
93
OPP: trigeminal stimulation
massage of trigeminal branches: ophthalmic (supraorbital, supratrochlear) and maxillary (infraorbital) >> glands of air sinuses to secrete watery fluid >> loosen mucous in sinuses to help drainage when congested
94
Torticollis
trauma or postural problems cause unilateral shortening of SCM >> head sidebent and rotated at rest
95
Emergency cricothyrotomy
-airway through cricothyroid membrane (easily palpable b/w thyroid and cricoid cartilage, no major vessels/nerves)
o Chronic airway (tracheotomy) – hole through tracheal cartilages (just superior to isthmus of thyroid) to prevent impingement of vocal cords
96
Injury to phrenic n.
damage can occur b/w neck and diaphragm >> paralysis of half of diaphragm, difficulty breathing; seen on radiographs as elevated dome of diaphragm on one side, but side with functional phrenic nerve is depressed
97
Injury to ansa cervicalis
-located anterior to carotid sheath, anterior and posterior roots most exposed to being cut >> elevated hyoid bone, difficulty swallowing
o Innervates infrahyoid strap mm.
98
Sinus drainage
- Sphenoid sinus>>sphenoethmoidal recess
- Posterior ethmoidal air cells>>superior meatus
- Maxillary and frontal sinus>>semilunar hiatus>>middle meatus
- anterior, middle ethmoidal air cells>>ethmoid bulla>>middle meatus
- nasolacrimal duct>>inferior meatus
- auditory tube>>nasopharynx
99
Infection of maxillary air sinus
-close relationship of maxillary sinus to upper teeth and superior alveolar nerves = infection can affect each other
o Oblique orientation of maxillary sinus’s orifice into middle meatus = drainage is difficult
-Medial wall of sinus can be breached artificially to allow irrigation and drainage if opening to maxillary sinus is inaccessible
100
Nose bleed (epitaxis)
veins of nasal cavities (swell bodies) easily torn; variety of arteries and anastomoses supply nasal cavity
101
Exophtalmos
globes of eyeball bulge anteriorly from orbit in certain conditions (goiter, Grave’s disease, hyperthyroidism, tumor, periorbital infection, cavernous sinus thrombosis)
102
Enophthalmos
eyeball posterior in socket (Horner syndrome)
103
Pupillary dilation
increased intracranial pressure in head injury >> compress CN III (as travels along tentorium cerebelli) >> persistent dilation of pupil
o CN III carries parasympathetic axons that cause constriction (so if affected, sympathetics take over to do unopposed dilation)
104
Occlusion of retinal arteries
central a. or retina is end artery (no anastomoses), if occluded >> permanent loss of vision in that eye
o Atherosclerosis can block these arteries
105
Development of tongue
tongue is motor and sensory, associated with 5 separate nerves
o CN V3 – tactile sensation
o Chorda tympani (br. of CN VII) – taste anterior 2/3
o CN IX – taste and general sensory posterior 1/3
o CN X – general sensory, taste info from small portion posterior tongue
o CN XII – motor
106
Development of extraocular nerves
mm. derive from three cranial somites, each supplied by separate cranial n.
o CN III – LPS, SR, MR, IR, IO
o CN IV – SO
o CN VI – LR
107
Fracture of dens
forceful flexion or extension places stress on dens >> posterior displacement of dens can cause impingement of spinal cord
o Fracture at base (thinner to accept the transverse ligament) may be asymptomatic
108
Anesthesia of laryngeal mucosa
comprising sensory nerves to larynx causes difficulty preventing fluids from entering trachea while swallowing; affected laryngeal mm. can make person unable to cough to expel substances
o Sensory superior to vocal cord = internal division of superior laryngeal n.
o Sensory inferior to vocal cord = inferior laryngeal n.
109
Paralysis of laryngeal mm.
damage to recurrent laryngeal n. >> de-innervate laryngeal mm. on affected side
o Posterior cricoarytenoid mm. – only muscles that ABDUCT the vocal folds
-Unilateral damage prevents speaking clearly
-Bilateral paralysis prevents breathing >> need emergency tracheotomy
110
OPP: atlanto-occipital membrane tension
posterior atlanto-occipital membrane implicated in neck pain because of association with dura mater at the foramen magnum
o Suboccipital facilitated oscillatory release and occipitoatlantal MFR – techniques to relieve tension in membrane and muscles to reduce pull on dura
111
OPP: review of Fryette's vertebral mechanics
o Thoracic and lumbar vertebrae in neutral position >>sidebending and rotation of group vertebrae in opposite directions
o Extension and flexion of thoracic and lumbar regions >>vertebrae sidebend and rotate in same direction at single vertebral segment
o Initiating motion in vertebral segment will modify movement of segment in other planes
112
Hyperacusis
paralysis of stapedius m. (CN VII) or tensor tympani (CN V3) cause heightened sensitivity to noise
o Stapedius m. increases tone to prevent stapes from impacting the oval window too violently when auditory input becomes too intense
113
7 bones of the orbit
Roof: frontal and lesser wing of sphenoid
Medial: ethmoid, lacrimal, frontal, and maxilla
Lateral: zygomatic, frontal, greater wing of sphenoid
Floor: maxilla, zygomatic, small part of palatine
114
3 layers of the eyeball
1. Fibrous (corneoscleral) tunic
2. vascular (uveal) tunic
3. retinal (sensory) tunic
115
Palatoglossus
Innervation: CN X
Actions: elevates tongue and depresses palate
116
Styloglossus m.
Innervation: CN XII
| Action(s): elevates tongue
117
Intrinsic muscles of the tongue
Innervation: CN XII
Action: move tongue
118
CN XII lesion
tongue deviation to affected side (lick your wounds)
119
Course of CN XII
-Emerges from hypoglossal nucleus of medulla oblongata>>leaves cranial cavity via hypoglossal canal>>descends lateral to vagus>>travels deep to digastric, stylohyoid, and mylohyoid mm and superficial to hyoglossus m>>enter root of tongue above hyoid
120
Modality of CN XII
GSE (somatomotor innervation to muscles of tongue)
121
Lesion to CN XI
- Susceptible during surgical procedures
| - weakness in shrugging (trapezius) and atrophy, impairment of rotatory movements of neck (SCM)
122
CN XI course
Originates from ventral horn of C4-C5>>GSE fibers to SCM and trapezius>>motor fibers exit along spinal nerves but ascend through foramen magnum then jugular foramen
123
CN IX origin
Lateral aspect of medulla oblongata
124
SVE function of CN IX
Motor to stylopharyngeus
125
Lesion in SVE of CN IX
weakness in swallowing
126
GVE function of CN IX
Parasympathetics to parotid gland
127
GVE lesion of CN IX
decreased salivation>>dry mouth
128
GSA function of CN IX
somatosensory info from pharynx (posterior 1/3 tongue, naso, oro, and laryngopharynx), Eustachian tube, ear drum and middle ear, part of external ear canal
129
GSA lesion of CN IX
difficulty swallowing, absence of gag reflex on ipsilateral side
130
GVA function of CN IX
- Chemoreceptors in carotid body (monitors O2 and CO2)
| - Pressure receptors in carotid sinus (monitors blood pressure)
131
GVA lesion of CN IX
difficulty maintaining body homeostasis, serious if bilateral
132
SVA function of CN IX
-taste input from posterior 1/3
133
SVA lesion of CN IX
loss of taste
134
CN X origin
rootlets from lateral aspect of medulla
135
SVE function of CN X
-majority of motor fibers to pharynx, larynx, and upper esophagus
136
inferior laryngeal nerve innervates...
all internal muscles of larynx
137
External branch of superior laryngeal nerve innervates...
cricothyroid
138
Internal branch of superior laryngeal nerve innervates...
Sensory to larynx
139
Lesion in SVE of CN X
loss of gag reflex, dysphagia, dysphonia, aphonia
140
Cricothyroid
Function: tense vocal fold, raise pitch
Innervation: external laryngeal n.
141
Thyroarytenoid and vocalis
Function: relax vocal fold, lower pitch
Innervation: inferior laryngeal n.
142
Posterior cricoarytenoid
Function: abduct vocal fold, raise volume
Innervation: inferior laryngeal n.
143
Lateral cricoarytenoid and arytenoids
Function: adduct vocal fold, lower volume
Innervation: inferior laryngeal n.
144
Pharyngeal gag reflex arc
CN IX mediates afferent limb
| CN X mediates efferent limb
145
Palatal reflex
CN V2 mediates sensory, CN X mediates motor
146
Unilateral lesion in palatal reflex
Uvula deviation to normal side
147
GVE function of CN X
Parasympathetics to thoracic and abdominal viscera
148
GVE lesion in CN X
increased HR, decreased gut peristalsis and sounds, decreased secretions from digestive glands (sympathetics take over)
149
GSA function of CN X
Somatosensory info from portions of dura mater, larynx and epiglottis region, part of external auditory canal
150
Arnold's reflex
- Ear-cough reflex
- When auricular branch of vagus is stimulated it can trigger a cough reflex
- Example: someone using a q-tip
151
GSA lesion in CN X
loss of conscious perception of these areas
152
GVA function of CN X
non-painful viscerosensory info from thoracic and abdominal viscera and baroreceptors or pressure sensors of aortic arch
153
GVA lesion of CN X
loss of visceral reflexes>>decreased visceral function
154
SVA function of CN X
special taste buds on epiglottis
155
SVE lesion of CN X
loss of taste sensation from epiglottis (not noticeable)
156
Anterior cavity of eye
From cornea to back of lens; filled with aqueous humor
- Anterior chamber - cornea to iris
- Posterior chamber - iris to lens
157
Posterior cavity of eye
From lens to back of eye; filled with vitreous humor
158
Characterization of Horner syndrome having to do with the eyelid muscles
Ptosis
159
Eyelid structures
- tarsal plates (dense bands of CT, contain tarsal glands)
- medial palpebral lig. (attachment of orbicularis oculi)
- lateral palpebral lig.
- orbital septum (continuous with periosteum, boundary for orbital fat and can limit spread of infection)
160
Orbital cellulitis
- Less common
- Infection posterior to the orbital septum
- More serious- can involve nerves, muscles, vision, etc.
- Usually secondary to infection of paranasal sinuses
161
Preseptal cellulitis
- More common
- Infection anterior to the orbital septum
- Less serious- typically no vision or oculomotor involvement
- Usually secondary to skin trauma, insect bite, etc.
162
Innervation to lacrimal gland
Preganglionic parasympathetic from CN VII>>pterygopalatine ganglion>>postganglionic fibers to zygomatic n.>>lacrimal n.>>lacrimal gland
163
CN III superior and inferior division
Superior: somatic motor to SR and levator palpebrae superioris
Inferior: somatic motor to MR, IR, and IO; preganglionic parasympathetic to ciliary ganglion (post-synaptic fibers via short ciliary nn. to sphincter pupillae and ciliary mm.)
164
CN VI (abducent) palsy
- LR paralyzed, MR unopposed
| - Patient would be unable to abduct eye (affected eye fixed in adduction)
165
CN IV (trochlear) palsy
- SO paralyzed, IO unopposed
| - patient unable to look in and down, affected eye is up and in
166
CN III (oculomotor) palsy
SR, IR, MR, IO all paralyzed, LR and SO work unopposed
| -affected eye down and out (often will be ptosis and pupillary involvement)
167
Facial vein thrombophlebitis
- facial v. communicates with superior ophthalmic vein>>drains to cavernous sinus
- infection/clot in face can travel to cavernous sinus (VEINS ARE VALVELESS)>>cavernous sinus thrombosis
