Week 1 - Severson Flashcards
(144 cards)
1
Q
What layers make up the scalp?
A
S: Skin C: Connective tissue (superificial fascia) A: Aponeurosis L: Loose connective tissue P: Pericranium/Periosteum
1
Q
In what layer are the major blood vessels and nerves of the scalp?
A
Connective tissue layer (superficial fascia)
2
Q
Why is bleeding so perfuse with scalp injuries?
A
Because they are tethered open by surrounding connective tissue. The blood vessels also anastomose freely and hemorrhage cannot be controlled by compressing any single vessel.
3
Q
What are the major dangers of scalp wounds?
A
Infectious processes may arise subcutaneously in the scalp and progress intracranially via the Diploic/Emissary veins that drain into the dural venous sinuses (eventually could involve the meninges –> meningitis).
4
Q
What do the areas of the fontanelles become later in life?
A
Anterior fontanelle –> Bregma Posterior fontanelle –> Lambda
5
Q
The superficial veins of the scalp connect to the dural sinuses by means of the _______?
A
Emissary veins
6
Q
What layer of the scalp are the diploic veins are located in?
A
Between the two bony layers of the skull.
7
Q
The superficial temporal arter is a terminal branch of the ______?
A
External carotid artery
8
Q
The auriculotemporal nerve supplying the temporal region of the head is a sensory branch of the _________ nerve.
A
Mandibular division (V3) of the Trigeminal nerve
9
Q
What is the pericranium and endocranium?
A
Pericranium = outer periosteum Endocranium = inner periosteum (periosteal layer of dura)
10
Q
What are the paranasal sinuses and where are they located?
A
- Frontal sinuses - above bilateral eyebrows 2. Ethmoid sinuses - under frontal lobe/below cristal galli area 3. Sphenoid sinuses - under sella turcica 4. Maxillary sinuses - above teeth/below nose bilaterally
11
Q
Define the 3 cranial fossae and their contents.
A
- Anterior cranial fossa - frontal lobe –> lesser wings 2. Middle cranial fossa - greater wings –> petrous part (ridge) 3. Posterior cranial fossa - jugular foramen –> occipital lobe/cerebellum
12
Q
Where are the ventricles of the brain located?
A
- Lateral ventricles - under Corpus Callosum 2. Third ventricle - Thalamus & Hypothalamus 3. Fourth ventricle - Anterior to Cerebellum
13
Q
What are the two major blood vessels supplying the brain?
A
- Internal Carotid Arteries 2. Vertebral arteries
14
Q
How does the newborn skull differ from that of the adult?
A
-Cranium larger than face -No dipole or mastoid process -Fontanelles where fibrous tissue and cartilage connect the frontal, parietal, and occipital skull bones (fuse ~2yoa)
15
Q
What are the major divisions of the brain?
A
- Cerebral hemispheres 2. Brainstem 3. Cerebellum
16
Q
The middle meningeal artery enters the cranial cavity through the _____?
A
Foramen Spinosum
17
Q
The arachnoid granulations that extend into the dural sinuses are formed by the _____ layer.
A
Arachnoid layer of the meninges
18
Q
Which layer of the dura is responsible for the formation of the dural reflexions?
A
Meningeal layer
19
Q
Where are the dural sinuses are located?
A
in or between the meningeal and the periosteal layers of the dura
20
Q
Where are the cerebral veins located?
A
Pial membrane
21
Q
What vessel is usually ruptured in a patient that has a subarachnoid hemorrhage?
A
Cerebral artery
22
Q
What dural reflexion separates supratentorial structures from posterior fossa structures?
A
Tentorium cerebelli
24
Q
CN I
Name
Sensory/Motor –> Innervation
Cell body location
Course
A
Olfactory - sensory - Olfactory epithelium
Cell body –> Olfactory epithelium
Through cribiform plate of ethmoid.
25
CN II
Name
Sensory/Motor --\> Innervation
Cell body location
Course
Optic - sensory - retina (bipolar cells)
Cell body --\> ganglionic layer of retina
From orbit through optic canal to optic chiasm, optic tract
26
CN III
Name
Sensory/Motor --\> Innervation
Cell body location
Course
Oculomotor - motor - 4 eye muscles
Cell body --\> oculomotor nucleus
Superior Orbital fissure.
27
CN IV
Name
Sensory/Motor --\> Innervation
Cell body location
Course
Trochlear - motor - superior oblique eye muscle
Cell body --\> trochlear nucleus
Superior orbital fissure.
28
CN V
Name
Sensory/Motor --\> Innervation
Cell body location
Course
Trigeminal - sensory/motor
V1 - Ophthalmic - sensory - face, nose, mouth, supratentorial dura
V2 - Maxillary - sensory - proprioception from head, TMJ, and tooth sockets
V3 - Mandibular - motor - muscles of mastication, tensors tympani and veli palatini, mylohyoid, anterior digastric
29
CN VI
Name
Sensory/Motor --\> Innervation
Cell body location
Course
Abducens - motor - lateral rectus eye muscle
Cell body --\> abducens nucleus
Superior orbital fissure.
30
CN VII
Name
Sensory/Motor --\> Innervation
Cell body location
Course
Facial - motor/sensory - muscles of facial expression, stylohyoid, posterior digastric, stapedius, glands of nose, palate, lacrimal gland, submandibular sublingual glands, taste buds, external auditory meatus, and skin on back of ear.
Course: Internal acoustic meatus to exit stylomastoid foramen, greater petrosal to pterygopalatine ganglion, chorda tympani to submandibular ganglion.
31
Through what passageway does the facial nerve exit the skull?
Stylomastoid foramen
31
Through what passageway does the facial nerve exit the cranial cavity?
Internal auditory (acoustic) meatus
32
Which of the following structures is NOT found in the posterior fossa? A. Cerebellum B. Cerebrum C. Facial nerve D. Midbrain E. Pons
B. Cerebrum
33
What blood vessel is most likely to produce an epidural or extradural hematoma?
Rupture of meningeal artery.
34
Between what two structures is an epidural hematoma confined?
bone and dura (lens shape on radiography).
35
What blood vessel is most likely to produce a subdural hemorrhage?
Rupture of a cerebral vein.
36
Between what two structures is an subdural hematoma confined?
dura & arachnoid membranes (blood accumulates in subdural space on radiography)
37
What blood vessel is most likely to produce a subarachnoid hemorrhage?
Rupture of a cerebral artery.
38
Between what two structures is an subarachnoid hematoma confined?
arachnoid membrane & the pia
40
What is the pterion? What is it's significance?
-region where frontal, parietal, temporal and spenoid join together -considered weakest part of the skull
41
Where is the location of the limbic lobe?
Medial aspect of each hemisphere, completely surrounding the corpus callosum and diencephalon.
42
What does the limbic lobe consist of?
-Septal or subcallosal area -Clingulate gyrus -Isthmas of the cingulate gyrus -Parahippocampal gyrus -Hippocampal formation (Subiculum, Dentate gyrus, & Hippocampus)
43
What is the function of the limbic lobe?
-Anterior part: Involved in emotional behavior & homeostasis -Posterior part: Involved in the cortical processes of learning and memory (consolidation of memories - declarative)
44
Where is the Olfactory cortex located?
Piriform cortex (area covering part of amygdaloid nucleus) + Lateral entorhinal cortex (small anterior region of the anterior parahippocampal gyrus)
45
What is the function of the Olfactory Cortex?
-Perception of odors -Discrimination and identification of odors
46
Where is the Insular cortex?
Buried in the depths of the lateral sulcus; covered by the frontal, parietal, and temporal opercula; lateral to the basal ganglia (lentiform nucleus); continuous with the anterior perforated substance on the ventral surface of the brain in the area known as the limen insulae.
47
What is the function of the Insular Cortex?
Serves to integrate visceral input: -olfactory, gustatory, and general sensory info -AKA: smell, taste, pain, thermal
48
What is the major blood supply of the Internal Capsule?
-Central/ganglionic branches of the middle cerebral artery
49
What are projection neurons?
Axons projecting TO or FROM the cerebral hemispheres.
50
What are the two terminal branches of the external carotid artery?
1. Facial artery 2. Superficial temporal artery
51
What are several major branches of the maxillary artery and through what foramina do they pass?
1. Inferior alveolar artery 2. Middle (and accessory) Meningeal artery - enters through foramen spinosum 3. Infraorbital and posterior superior alveolar arteries 4. Muscular branches (e.g. masseteric, temporal, pterygoid)
52
Through which fissure does the maxillary artery pass?
Pterygomaxillary fissure
53
Where does the maxillary artery terminate?
Pterygopalatine fossa (whereafter it divides)
54
What are the two terminal branches of the maxillary artery?
Sphenopalatine & Descending palatine branches
55
Where is the pterygoid plexus of veins located?
Surrounds the lateral pterygoid muscle
56
What anastomotic connections does the pterygoid plexus of veins have with the facial vein and the cavernous sinus?
Communicates with the facial vein via the deep facial vein and with the cavernous sinus through the foramen ovale (spread of infection).
57
With what bone does the mandible articulate?
Articular surface of the temporal bone
58
How does the TMJ joint differ from most synovial joints?
An articular disc divides the joint into upper and lower cavities. Upper cavity = gliding movement Lower cavity = hinge movement
59
What ligaments are associated with the TMJ?
-Lateral ligament (temporomandibular ligament) -Sphenomandibular -Stylomandibular
60
What happens with dislocation of the TMJ?
Anterior dislocations (subluxations) are most common where the head passes anterior to the tubercle of the temporal bone. Results in difficulty closing the mouth.
61
What is the nerve supply of the TMJ?
Mandibular branch (V3) of the Trigeminal Nerve
62
What branches of the trigeminal nerve are sensory to the face?
V1 - Ophthalmic Nerve --\> Supraorbital nerve
V2 - Maxillary Nerve --\> Infraorbital nerve
V3 - Mandibular Nerve --\> Mental Nerve
63
What is Trigeminal Neuralgia or *tie douloureux*?
* Sensory disorder of the sensory root of CN V
* Most often V2\>V3\>V1
* Sudden paroxysmal attacks of excruciating facial pain like lightning jabs
* Pain is often initiated by touching a sensitive trigger zone of the skin
64
What are the major arteries of the face?
* External Carotid branches:
* **Facial artery**
* **Superficial temporal artery**
* **Transverse facial artery**
* ****Ophthalmic Artery branches
* **Supraorbital artery**
* **Supratrochlear artery**
65
What is significant about the veins of the face?
The veins of the face are ***valveless***.
66
How can infections from the face spread into the dural venous sinuses?
Connections with deeper venous plexus
(pterygoid and cavernous sinus collections).
Infectious processes in superficial veins draining the upper lip and nose may often end up in deeper veins and cause concern for involvement with such structures as the brain.
67
Where are the lymph nodes associated with the head located?
Lymph from the lateral part of the face and scalp drains into the **Superficial Parotid Lymph Nodes**.
68
What are the four muscles of facial expression that we need to recognize?
1. Orbicularis oculi
2. Orbicularis oris
3. Buccinator
4. Platysma
69
Where do the four muscles of facial expression originate and insert?
Arise from bones of the skull
Insert into the skin
70
What nerve innervates the Orbicularis oculi?
CN VII Facial Nerve
| (Zygomatic branch)
71
What nerve innervates the Orbicularis oris?
CN VII Facial Nerve
72
What nerve innervates the Buccinator?
CN VII Facial Nerve
| (buccal branch)
73
What nerve innervates the Platysma?
CN VII Facial Nerve
| (cervical branch)
74
What foramen does the facial nerve enter upon leaving the cranial cavity?
Internal Auditory (Acoustic) Meatus
75
From what foramen does the Facial Nerve exit the cranial cavity?
Stylomastoid Foramen
76
What are the five branches of the facial nerve?
1. Temporal
2. Zygomatic
3. Buccal
4. Marginal Mandibular
5. Cervical
77
What *structure* does the Facial Nerve enter upon leaving the skull?
Parotid Gland
78
In addition to the muscles of facial expression, what other muscles are innervated by the facial nerve?
* Auricular muscles (wiggle ears)
* Occipitofrontalis (scalp muscles)
* Stapedius (inner ear)
* Stylohyoid (muscle below chin)
* Posterior belly of the digastric (muscle off of Stylus)
79
What type of nerve fibers are found in the Chorda tympani?
Sensory fibers
| (special visceral afferent - SVA)
80
How does the chorda tympani reach its destination?
The chorda tympani travels with the Lingual nerve (branch of Mandibular Nerve V3) to reach the base of the tongue.
81
What is Bell's Palsy?
* Paralysis of the facial muscles (does not spare the eyebrows and forehead).
* Inability to close the lips, eyes, or chew effectively.
* Due to interruption of CN VII - Facial Nerve.
* Can be associated with exposure to the cold or tumor of the parotid gland.
82
What nerve supplies the Masseter Muscle?
V3 - Mandibular Division of
CN V (Trigeminal Nerve)
83
What is the function of the Masseter Muscle?
Raises the mandible,
Mastication
84
Through what foramen does the Mandibular Division (V3) of the Trigeminal Nerve (CN V) exit the cranial cavity?
Foramen Ovale
85
How does the Mandibular Division (V3) of the Trigeminal Nerve (CN V) reach its destination in the masseter muscle?
Masseteric Nerve - motor branch of V3 Mandibular Division (Trigeminal Nerve - CN V)
86
What is the relationship of the parotid gland to the ramus of the mandible?
Location.
The parotid gland is wedged between the ramus of the mandible and the mastoid process.
87
What nerve and blood vessels are found within the parotid gland?
* Nerve - deep portion of the facial nerve CN VII and its branches
* Blood Vessels
* Retromandibular vein
* External carotid artery
88
What are the boundaries of the temporal fossa?
1. Superior temporal line
2. Frontal process of zygomatic bone
3. Zygomatic arch
89
What is the function of the Temporalis muscle?
Elevates and retracts the mandible
Mastication
90
What nerve innervates the Temporalis Muscle?
Deep Temporal Nerve (CN V3)
Mandibular Division (V3) of the Trigeminal Nerve (CN V)
91
What are the boundaries of the infratemporal fossa?
1. Posterior suface of the maxilla
2. Styloid process
3. Greater wing
4. Lateral pterygoid plate of sphenoid
5. Ramus of the mandible
92
What are the two muscles in the infratemporal fossa?
1. Lateral pterygoid muscle
2. Medial pterygoid muscle
93
What is the origin and insertion of the Lateral pterygoid muscle?
Origin: Infratemporal surface of greater wing of sphenoid and lateral surface of the lateral pterygoid plate
Insertion: capsule of the TMJ, neck of mandible, and articular disc of TMJ
94
What is the origin and insertion of the Medial pterygoid muscle?
Origin: Medial surface of the lateral pterygoid plate and maxillary tuberosity
Insertion: Medial surface of the angle of the mandible
95
How does the Lateral pterygoid muscle function in jaw movements?
Protrudes and depresses the mandible
| (mastication)
96
How does the Medial pterygoid muscle function in jaw movements?
Protrudes and elevates the mandible
97
What nerve innervates the Lateral and Medial pterygoid muscles?
CN V3
98
What are the four major sensory branches of the mandibular nerve?
1. Auriculotemporal
2. Lingual
3. Inferior alveolar
4. Buccal
99
The auriculotemporal nerve is sensory to what area of the head?
* Skin of the temple
* External auditory meatus
* TMs
* TMJ
100
What is the relationship of the auriculotemporal nerve to the zygomatic arch?
Passes superifical to Zygomatic arch
101
What viseral motor fibers are found in the Auriculotemporal nerve?
Postganglionic parasympathetic fibers from the
Otic Ganglion
102
What area is supplied by the lingual nerve for general sensation?
Anterior 2/3 of the tongue, floor of the mouth, and gums
103
Where do the preganglionic parasympathetic fibers of the chorda tympani terminate?
Submandibular ganglion
104
What do the postganglionic fibers of the Submandibular Ganglion innervate?
Submandibular Glands
&
Sublingual Salivary Glands
105
What area do the special visceral afferent fibers (taste fibers) of the Chorda Tympani innervate?
anterior 2/3 of the tongue
106
What are the cell bodies of the special visceral afferent fibers (taste fibers) of the Chorda Tympani?
Geniculate Ganglion
107
Through which foramen does the inferior alveolar nerve ENTER the mandible?
Mandibular foramen
108
Through which foramen does the inferior alveolar nerve EXIT the mandible?
Mental foramen
109
What is the terminal sensory branch of the inferior alveolar nerve?
Mental Nerve
110
What motor nerve arises from the inferior alveolar nerve?
Mylohyoid Nerve
111
What muscles are innervated by the Mylohyoid Nerve?
* Mylohyoid muscle
* Anterior belly of the Digastric Muscle
112
What area is supplied by the Buccal Nerve?
Cutaneous surface of the cheek and
mucous membranes
113
What nerve supplies the buccinator muscle?
Facial nerve
114
What are the motor nerves of the mandibular division - V3 of the Trigeminal Nerve (CN V)
1. Masseteric Nerve (masseter muscle)
2. Deep Temporal Nerves (2, temporalis muscle)
3. Medial Pterygoid Nerve (medial pterygoid msk)
4. Lateral Pterygoid Nerve (lateral pterygoid msk)
5. Nerves to Tensor Tympani
6. Nerves to Tensor Veli Palatini
115
What muscles are innervated by the Trigeminal Nerve?
* Muscles of mastication
* Tensors tympani
* Tensor Veli Palatini
* Mylohyoid
* Anterior Digastric
116
Do the Ophthalmic and Maxillary Divisions of the Trigeminal Nerve (CN V) have motor fibers?
NO
117
What cranial nerve and specific peripheral nerve carry preganglionic fibers to the Otic Ganglion?
The ganglion receives preganglionic parasympathetic fibers via the lesser petrosal nerve (branch of CN IX - Glossopharyngeal Nerve).
118
How do the postganglionic fibers reach the parotid gland?
Postganglionic fibers travel with the Auriculotemporal nerve (branch of CN V3) to the parotid gland.
119
Why do facial lacerations tend to gape?
The face does not have a distinct layer of deep fascia and the subcutaneous tissue is loose between the attachments of the facial muscles.
120
What are the two major arterial supplies to the brain?
1. Internal carotid artery
2. Vertebral arteries
121
How does the Internal carotid artery enter the skull?
Enters the base of the skull through the
**Carotid Canal**.
122
What artery does the Vertebral artery originate from?
Subclavian artery
123
What does the Vertebral artery travel through in the neck?
Transverse Foramen of cervical vertebrae 1-6
124
How does the Vertebral Artery enter the skull?
Foramen Magnum
125
What are the two terminal branches of the Internal carotid artery?
1. Middle Cerebral artery (insular cortex --\> lateral fissure)
2. Anterior Cerebral artery (longitudinal fissure)
126
What are the collateral branches of the internal carotid arteries?
1. Hypophyseal arteries (supply pituitary/hypothalamus)
2. Ophthalmic arteries (supply orbit/optic nerve)
3. Posterior communicating arteries (joins the vertebral & carotid systems)
4. Anterior choroidal arteries (supply choroid plexus)
127
What are the collateral branches of the Vertebral artery?
1. Anterior spinal artery (supplies medulla)
2. Posterior spinal artery (supplies medulla)
3. Posterior inferior cerebellar arteries (PICA - supplies cerebellum)
4. Basilar artery (union of the two vertebral arteries)
128
What are the collateral branches of the Basilar artery?
1. Anterior inferior cerebellar arteries (cerebellum, medulla, pons)
2. Internal auditory (labyrinthine) arteries (inner ear)
3. Pontine arteries (pons)
4. Superior cerebellar arteries (cerebellum, pons, midbrain)
129
What are the terminal branches of the Basilar artery?
Posterior cerebral arteries
130
What do the Posterior Cerebral arteries supply?
1. Inferior temporal lobe
2. Medial parietal lobe
3. Medial occipital lobe
131
What are the Calcarine branches and why are they important?
* Branches of the Posterior Cerebral Arteries
* Supply visual cortex at the occipital pole and along the calcarine fissure.
* Occlusion produces blindness in contralateral visual field.
132
What artery do most strokes involve?
Distribution of the MIDDLE CEREBRAL ARTERIES
133
What are the major cerebral arteries that make up the Circle of Willis?
From Noon-6 Bilaterally:
* Anterior communicating artery
* Anterior cerebral artery
* Internal carotid artery --\> middle cerebral artery
* Posterior communicating artery
* Posterior cerebral artery
* Basillar artery
134
What structures does the Circle of Willis incircle?
* Optic chiasm
* Pituitary
* Cranial nerves
* Cavernous sinus
135
What do the cortical branches of the Circle of Willis supply?
* Circumferential
* travel over the brain surface in the subarachnoid space to supply outer surface of the brain
136
What do the central branches of the Circle of Willis supply?
* Ganglionic or Perforating
* Penetrate deep into the hemispheres from the ventral surface
137
What is the clinical significance of the Middle cerebral artery?
* Carries 80% of the blood to the cerebral hemispheres
* Interruption may produce contralateral paralysis and sensory deficits
* primarily in: head, arm, and UPPER body
* if damage is in the left hemisphere, there is usually difficulty with speech and/or understanding
138
What is the clinical significance of the Anterior cerebral arteries?
* If the pre- and postcentral gyri of the paracentral lobule are affected, there will be paralysis and sensory loss in the contralateral LOWER extremity
139
Occlusion of what produces Lateral Medullary Syndrome?
Posterior Inferior Cerebral Artery (PICA)
140
Where do cerebral veins drain?
venous sinuses --\> internal jugular veins
141
What are four major features of cerebral veins?
1. Very thin walls
2. No valves
3. Cross the subarachnoid space after they emerge from the brain
4. Pierce the arachnoid and the meningeal layer of the dura to drain into the dural venous sinuses
142
Where do Superficial cerebral veins travel?
* Located in the subarachnoid space
* Generally travel over and in the fissures/sulci of the cerebral hemispheres
* Tend to empty into the nearest sinus
143
Where do Deep (Internal) cerebral veins travel?
* Collect from venous tributaries in the choroid plexus and various brain interior
* Begin at interventricular foramina as a pair of vessels
* Travel in a caudal direction beneath the corpus callosum and within the transverse cerebral fissure
144
Where does the Great cerebral vein travel?
Collects from the Deep (Internal) venis and empties into the straight sinus.
