Head Anatomy Flashcards
(169 cards)
1
Q
Muscular contributions of the first pharyngeal arch
A
- Muscles of mastication
- Anterior belly of digastric
- Mylohyoid
- Tensor tympani
- Tensor veli palatani
2
Q
Skeletal contributions of the first pharyngeal arch
A
- Maxilla
- Meckels cartilage
- Incus
- Malleus
3
Q
Vascular contributions of the first pharyngeal arch
A
- Maxillary
- External carotid
4
Q
Nervous contributions of the first pharyngeal arch
A
- Mandibular nerve
5
Q
Muscular contributions of the second pharyngeal arch
A
- Buccinator
- Platysma
- Muscles of facial expression
- Stylohyoid
- Posterior belly of digastric
- Stapedius
6
Q
Skeletal contributions of the second pharyngeal arch
A
- Stapes
- Styloid process
- Lesser horn and upper body of hyoid
7
Q
Vascular contributions of the second pharyngeal arch
A
- Inferior branch of superior thyroid artery
- Stapedial artery
8
Q
Nervous contributions of the second pharyngeal arch
A
- Facial
9
Q
Muscular contributions of the third pharyngeal arch
A
- Stylopharyngeus
10
Q
Skeletal contributions of the third pharyngeal arch
A
- Greater horn and lower part of body of hyoid
11
Q
Endocrine contributions of the third pharyngeal arch
A
- Thymus
- Inferior parathyroids
12
Q
Vascular contributions of the third pharyngeal arch
A
- Common carotid
- Internal carotid
13
Q
Nervous contributions of the third pharyngeal arch
A
- Glossopharyngeal
14
Q
Muscular contributions of the fourth pharyngeal arch
A
- Cricothyroid
- All intrinsic muscles of the soft palate
15
Q
Skeletal contributions of the fourth pharyngeal arch
A
- Thyroid cartilage
- Epiglottic cartilage
16
Q
Endocrine contributions of the fourth pharyngeal arch
A
- Superior parathyroids
17
Q
Vascular contributions of the fourth pharyngeal arch
A
- Right subclavian
- Left aortic arch
18
Q
Muscular contributions of the sixth pharyngeal arch
A
- All intrinsic muscles of the larynx (except cricothyroid)
19
Q
Skeletal contributions of the sixth pharyngeal arch
A
- Cricoid cartilage
- Arytenoid cartilage
- Corniculate cartilage
20
Q
Vascular contributions of the sixth pharyngeal arch
A
- Right pulmonary artery
- Left pulmonary artery
- Ductus arteriosus
21
Q
Nervous contributions of the sixth pharyngeal arch
A
- Vagus nerve
- Recurrent laryngeal nerve
22
Q
From which pharyngeal arches is the tongue derived from
A
1, 2, 3
23
Q
What embryological structures form the anterior 2/3rds of the tongue
A
Two lingual swellings arising from the tuberculum impar in the floor of the pharynx
24
Q
What nerve gives general sensation to the anterior 2/3rd of the tongue
A
Trigeminal nerve
25
What nerve transmits taste sensation from the anterior 2/3rd of the tongue
Chorda tympani - CN 7
26
Sensory and taste innervation from the posterior 1/3rd of the tongue
Both glossopharyngeal
27
Cause of cleft lip
Failure of fusion of the **maxillary** and **frontonasal** processes
28
Cause of cleft palate
Failure of fusion between **primary** and **secondary** palate
29
Where does the spine initially fuse embryologically
Thoracic region
30
Define meningocele
Meninges herniate through the bony defect and are covered by skin
31
Define meningomyelocele
Failure of closure of the neural tube. Defect formed by exposed neural tissue. Frequently accompanied by hydrocephalus.
32
Two parts of the cranium
1. Neurocranium
2. Viscerocranium
33
List the bones of the facial skeleton
- Mandible
- Ethmoid
- Vomer
- Maxillae
- Inferior nasal conchae
- Zygomatic
- Palatine
- Nasal
- Lacrimal
34
List the central bones of the neurocranium
- Frontal
- Ethmoidal
- Sphenoidal
- Occipital
35
List the lateral bones of the nuerocranium
- Paired temporal - Paired parietal
36
Describe the zygomatic bones
- 2 - Form the cheek bones - Articulate with the frontal, sphenoidal, temporal, and maxilla bones
37
Describe the lacrimal bones
- 2 - Smallest facial bones - Form the medial wall of the orbit
38
Describe the nasal bones
- 2 - Located on the bridge of the nose - Intersection between frontal and nasal bones = nasion
39
Describe the inferior nasal conchae
- 2 - Located within the nasal cavity - Increase the surface area of the nasal cavity
40
Describe the maxillae
- 2 - Comprise part of the upper jaw and hard palate - Unite at the intermaxillary suture - Contain the infraorbital foramen
41
Describe the Vomer
Forms the posterior aspect of the nasal septum
42
Describe the mandible and the nerves that course through it
- Ramus is the vertical part - Mandibular foramen lies on the medial aspect of the ramus and transmits the inferior alveolar nerve - Travels through canal in the body of the mandible to emerge through the mental foramen as the mental nerve
43
Describe the coronal suture
Fuses the frontal bone with the two parietal bones
44
Describe the sagittal suture
Fuses both parietal bones
45
Describe the lambdoid suture
Fuses the occipital bone to the two parietal bones
46
Describe the cranial vault
- Roof of the cranial cavity - Formed by frontal bone, parietal bones, occipital bones
47
What is the glabella
Prominence of the nasion, which is the depression between the two supraorbital margins
48
What is the pterion
- Thin part of the skull - Junction between parietal, temporal, frontal bones and greater wing of sphenoid
49
Describe the anterior cranial fossa
- Overlies the orbit and nasal cavities - Formed by the orbital plate of the frontal bones supplemented posteriorly by the lesser wing of sphenoid
50
What occupies the space between the orbital plates
Ethmoid bone with its cribriform plate and crista galli
51
What separates the anterior cranial fossa from the orbit
Orbital plates
52
What occupies the anterior cranial fossa
Frontal lobe of the brain
53
What passes between the anterior cranial fossa and the nasal cavity
- Olfactory nerves via cribriform plate
- Emissary veins via cribriform plate
- Anterior ethmoidal nerves, arteries, and veins via anterior part of cribriform plate
54
What sensation can be affected when the cribriform plate is fractured
Sense of smell
55
What bone contains the inner and middle ear
Petrous part of the temporal bone
56
Where is the pituitary gland located
Within the sella turcica within the sphenoid bone in the middle cranial fossa
57
Describe the bounds of the pituitary fossa
- Anterior = anterior clinoid process - Posterior = posterior clinoid process - Lateral = greater wing of sphenoid and squamous temporal - Floor = body of sphenoid
58
Fracture of what causes bleeding into the middle ear
Tegmen tympani
59
List the foramina contained within the middle cranial fossa
- Optic canal - Superior orbital fissure - Foramen rotundum - Foramen ovale - Foramen spinosum - Foramen lacerum
60
Bounds of the posterior cranial fossa
- Anterior wall = petrous temporal laterally and body of sphenoid medially - Floor and walls = occipital bone
61
List the foramen contained within the posterior cranial fossa
- Jugular foramen - Hypoglossal foramen - Foramen magnum - Internal acoustic meatus
62
Where can bleeding develop in fractures involving the posterior cranial fossa
Pharynx
63
Optic canal contents
- Optic nerve - Ophthalmic artery
64
Superior orbital fissure contents
- Oculomotor nerve - Trochlear nerve - Abducens nerve - Ophthalmic division of trigeminal - Ophthalmic veins - Sympathetic nerves
65
Foramen rotundum contents
- Maxillary division of trigeminal
66
Foramen ovale contents
- Mandibular division of trigeminal - Accessory meningeal artery
67
Foramen spinosum contents
- Middle meningeal artery - Meningeal branch of mandibular nerve
68
Foramen lacerum contents
- Internal carotid artery
69
Foramen magnum contents
- Medulla oblongata (continuing into spinal cord) - Accessory nerves - Vertebral arteries
70
Jugular foramen contents
- Internal jugular vein (continuation of sigmoid sinus) - Glossopharyngeal nerve - Vagus nerve - Inferior petrosal sinus
71
Hypoglossal canal contents
- Hypoglossal nerve - Meningeal branch of ascending pharyngeal artery
72
Internal auditory meatus contents
- Facial nerve - Vestibulocochlear nerve - Labyrinthine artery
73
Stylomastoid foramen
Site where facial nerve exits the skull
74
Site of the foramen spinosum
Greater wing of the sphenoid
75
List the 5 layers of the scalp
S-C-A-L-P 1. Skin 2. Connective tissue 3. Aponeurosis 4. Loose areolar tissue 5. Pericranium
76
Describe the role of the scalp aponeurosis
Tendinous sheet that serves as attachment for muscles converging from the forehead and occipitut and from the temporal bones
77
How are the muscles of the face divided
1. Muscles of mastication 2. Muscles of facial expression
78
Innervation of muscles of mastication
Mandibular division of the trigeminal nerve
79
Innervation of the muscles of facial expression
Facial nerve
80
Cutaneous innervation of the face and anterosuperior part of the scalp
Trigeminal nerve
81
Innervation of the inferior aspect of the auricle
Great auricular nerve
82
Innervation of the skin overlying the parotid and angle of jaw
Great auricular nerve
83
3 divisions of the mandibular nerve
1. Ophthalmic 2. Maxillary 3. Mandibular
84
Course of the ophthalmic nerve
- Superior most division
- Arises from trigeminal ganglion as wholly sensory nerve
- Enters orbit via supraorbital fissue
- Trifurcates into frontal, nasocilliary, lacrimal nerves
- Reach the skin of the face via the orbital opening
85
Divisions of the ophthalmic nerve
1. Frontal 2. Nasociliary 3. Lacrimal
86
Course of the maxillary nerve
- Arises as wholly sensory nerve - Leaves cranium via foramen rotundum - Enters pterygopalatine fossa giving branches to the ganglion - Enters orbit via inferior orbital fissure - Gives of zygomatic nerve and continues as the infraorbital nerve
87
Describe the course of the mandibular nerve
- Largest division - Formed by the union of motor and sensory fibres in the foramen ovale - Auriculotemporal branch of V3 conveys secretomotor fibres to the parotid gland
88
Outline the innervation of the scalp
- Anterior to the auricles = all 3 divisions of the mandibular - Posterior to the auricles = spinal cutaneous nerves C2 and C3
89
Describe the course of the facial nerve
- Origin: motor = pons, sensory = nervus intermedius - Passes through petrous temporal bone to internal auditory meatus - Passes superior to vestibule of inner ear - Contain geniculate ganglion -Exits cranium via stylomastoid foramen - Immediately gives off posterior auricular nerve and branch to posterior belly of digastric and stylohyoid - Main trunk runs through the parotid gland and gives off five branches
90
3 facial nerve branches prior to exiting cranium via stylomastoid foramen
1. Greater petrosal nerve 2. Nerve to stapedius 3. Chorda tympani
91
5 divisions of the facial nerve within the parotid plexus (The Zebra Buggered My Cat)
1. Temporal 2. Zygomatic 3. Buccal 4. Marginal mandibular 5. Cervical
92
Function of chorda tympani
1. Sensory innervation to the anterior 2/3rd of the tongue via the lingual nerve 2. Presynaptic parasympathetic fibres to the submandibular ganglion providing secretomotor innervation to submandibular and sublingual glands
93
Course of chorda tympani
- Exits cranial cavity via internal acoustic meatus - Travels through middles ear - Runs medial to pars flaccida as it travels across tympanic membrane - Emerges into infratemporal fossa
94
Course of the lingual nerve
- Arises from posterior trunk of mandibular nerve - Passes tensor veli palatani and lateral pterygoid where it is joined by chorda tympani - Lies close to medial aspect of mandibular ramus - At junction between horizontal and vertical rami it is anterior to inferior alveolar nerve - Lies on periosteum of 3rd molar tooth - Wraps around wharton's duct
95
Describe the course and distribution of the temporal nerve
- Emerges from superior border of parotid - Crosses zygomatic arch - Supplies auricularis superior and anterior - Supplies belly of occipital frontalis and superior part of orbicularis oculi
96
Describe the course and distribution of the zygomatic nerve
- Supplies inferior part of orbicularis oculi - Supplies facial muscles inferior to orbit
97
Describe the course and distribution of the buccal branch of the facial nerve
- Passes external to buccinator to supply it
- Supplies other muscles of upper lip
98
Describe the course and distribution of the marginal mandibular nerve
- Emerges from inferior border of parotid - Crosses inferior border of mandible - Supplies risorius and muscles of lower lip and chin
99
Describe the course and distribution of the cervical branch of the facial nerve
- Passes inferiorly from inferior border of parotid - Runs posterior to mandible - Supplies platysma
100
Describe the course and distribution of the facial artery
- Branch of external carotid - Passes over lower border of mandible with anterior border of masseter - Closely related to submandibular gland (at risk during surgery)
101
Where is the vascular layer of the scalp
Between the subcutaneous connective tissue and epicranial aponeurosis
102
Arterial supply to the neurocranium
Middle meningeal artery
103
What forms the retromandibular vein
Union of: - Superficial temporal vein - Maxillary vein
104
What vein drains the pterygoid venous plexus
Maxillary vein
105
Describe the course of the course of the retromandibular vein
- Runs posterior to ramus of mandible within the parotid - Superficial to external carotid - Deep to facial nerve - Emerges from inferior pole of parotid - Divides into anterior and posterior branches - Anterior unites with facial vein - Posterior forms EJV with posterior auricular vein
106
What forms the EJV
1. Posterior branch of retromandibular vein 2. Posterior auricular vein
107
What drains the sigmoid sinus
Internal jugular vein
108
Outline the lymphatic drainage of the face
- Lateral face and scalp, including eyelids, to superficial parotid nodes - Deep parotid nodes to deep cervical nodes - Upper lip and lateral lower lip to submandibular nodes - Chin and central lower lip to submental nodes
109
Outline the 3 layers of the cranial meninges
1. Dura mater - thick external fibrous layer 2. Arachnoid mater - thin intermediate layer 3. Pia mater - delicate vascular layer
110
What forms the leptomeninx
Arachnoid and pia mater - they are continuous membranes
111
Describe the strucutre of the dura mater
Two layers: 1. External periosteal layer - adheres to calvaria, NOT continuous with dura of spinal cord 2. Internal meningeal layer - continues at foramen magnum
112
What are the dural reflections (infoldings)
Internal meningeal layer reflects away from the external periosteal layer
113
List the 4 dural septa
1. Falx cerebri 2. Tentorium cerebelli 3. Falx cerebelli 4. Diaphragma sellae
114
Significance of the diaphragma sellae
Covers the pituitary gland in the hypophysial fossa in the sphenoid
115
Where are the dural venous sinuses generally situated
Between the periosteal and meningeal layers of the dura mater
116
How does CSF enter the venous system
Via arachnoid granulations
117
Describe the superior sagital sinus
- Lies in the border of falx cerebri - Begins at crista galli - Ends at the confluence of sinuses
118
Outline the components of the confluence of sinuses
1. Superior sagittal 2. Straight 3. Occipital 4. Transverse
119
What forms the straight sinus
Formed by the union of the inferior sagittal sinus with the great cerebral vein
120
Where is the inferior sagital sinus situated
Inferior free edge of the falx cerebri
121
Fate of the transverse sinuses
Sigmoid sinuses
122
Where is the cavernous sinus situated
Located on each side of the sella turica on the upper surface of the body of the sphenoid
123
List the tributaries of the cavernous sinus
1. Superior and inferior ophthalmic veins 2. Superficial middle cerebral vein 3. Sphenoparietal sinus
124
Where does the cavernous sinus drain
Basilar and pterygoid plexuses via superior and inferior petrosal sinuses and emissary veins
125
What is contained within the cavernous sinus
1. Internal carotid artery 2. Carotid plexus of sympathetic nerves 3. Abducens nerve
126
What is embedded within the walls of the cavernous sinus
1. CN 3 2. CN 4 3. CN 5
127
What connects the dural venous sinuses to veins outside of the cranium
Emissary veins
128
Primary blood supply to the dura
Middle meningeal artery
129
Describe the extradural space
- Not a natural space
- Pathological space between cranium and external periosteal layer of dura
- Typically arises from rupture of the middle meningeal artery
130
Describe the subdural space
- Not natural
- Pathological as a result of trauma
- Between dura and arachnoid
131
Describe the subarachnoid space
- Natural space
- Between arachnoid and pia mater
132
What is the contents of the subarachnoid space
Only naturally occurring space
- CSF
- Trabecular cells
- Arteries and veins
133
List the lobes of each hemisphere
1. Parietal
2. Frontal
3. Temporal
4. Occipital
134
What separates the frontal and parietal lobes
Central sulcus
135
What separates the occipital lobe from the parietal and temporal lobes
Parieto-occipital sulcus
136
What constitutes the diencephalon
- Epithalamus
- Thalamus
- Hypothalamus
137
Which cranial nerves are associated with the midbrain
- CN 3
- CN 4
138
Where is the pons located
- Part of the brainstem
- Between midbrain rostrally and the medulla oblongata caudally
139
Which cranial nerve is associated with the pons
CN 5
140
What constitutes the brainstem
- Midbrain
- Pons
- Medulla oblongata
141
Which cranial nerves are associated with the medulla oblongata
CN 9, 10, 12
142
What connects the lateral ventricles to the 3rd ventricle
Aqueduct of Monro
143
What connects the 3rd and 4th ventricles
Aqueduct of Sylvius
144
Where is the 3rd ventricle situated
Slit-like cavity between the right and left halves of the diencephalon
145
How does CSF reach the subarachnoid space from the 4th ventricle
Through a single median aperture and paired lateral apertures
146
How much CSF is produced per day
400-500ml/day
147
Where is CSF produced
Choroidal epithelial cells of the choroid plexus in the ventricles
148
What is the fate of the majority of the CSF leaving the 4th ventricle
- The majority enters the interpeduncular and quadrigeminal cisterns
- Then flows superiorly through the sulci and fissules on the medial and superolateral cerebral hemispheres
149
Where is the primary site of absorption of CSF into the venous system
Via arachnoid granulations into the dural venous sinuses
150
What proportion of cardiac output does the brain receive
1/6th
151
Where do the internal carotid arteries enter the cranium
Via carotid canal
152
What joins the internal carotid on its route through the cavernous sinus
CN 6 (Abducens nerve)
153
Terminal branches of the internal carotid
- Anterior cerebral artery
- Middle cerebral artery
154
What connects the anterior cerebral arteries
Anterior communicating artery
155
What connects the internal carotid arteries to the posterior cerebral arteries
Posterior communicating arteries
156
Clinically, what does the internal carotid artery and its branches make up
Anterior circulation of the brain
157
Origin of the vertebral arteries
- First branches of subclavian arteries
- Begin in the root of the neck
158
Which verterbral artery is bigger
Left
159
How do the vertebral arteries enter the cranium
Via foramen magnum
160
What is formed from the unity of the vertebral arteries at the caudal border of the pons
Basilar artery
161
What is the fate of the basilar artery
Ascends and divides into two posterior cerebral arteries
162
What part of the brain is supplied by the anterior cerebral artery
Cerebral hemispheres (except from occipital lobe)
163
What part of the brain is supplied by the middle cerebral artery
Lateral surface of the brain and temporal pole
164
What part of the brain is supplied by the posterior cerebral artery
Inferior surface of the brain and the occipital pole
165
What forms the circle of Willis
- Anterior communicating artery
- Anterior cerebral arteries
- Internal carotid arteries
- Posterior communicating arteries
- Posterior cerebral arteries
166
What is supplied by the vertebral arteries
Cranial meninges and the cerebellum
167
Where do the superior cerebral veins drain
Superior sagittal sinus
168
Describe the great cerebral vein (of Galen)
- Midline vein formed inside the brain
- Ends by merging with inferior sagittal sinus to form the straight sinus
169
Outline the venous drainage of the cerebellum
- Superior and inferior cerebellar veins
- Drain into the transverse and sigmoid sinuses
