Anatomy theme 8 Flashcards
1
Q
What does the external ear consist of ?
A
auricle , ext. auditory meatus and tympanic membrane
2
Q
What does the middle ear consist of ?
A
ossicles and the muscles (stapedius and tensor tympani)
3
Q
What is the epitympanic recess ?
A
small part of of the inner ear extends above the tympanic membrane as the epitympanic recess
4
Q
Where is the tensor tympani muscle ?
A
in part of the pharyngotympanic tube
5
Q
What are the ossicles ?
A
malleus , incus and stapes
6
Q
Where is the inner ear found ?
A
medial to the tympanic cavity in the petrous temporal bone
7
Q
What is the embryonic derivation of the tubotympanic recess ?
A
1st pouch
8
Q
What is the embryonic derivation of malleus and incus ?
A
meckels cartilage - 1st pharyngeal, arch
9
Q
What is the embryonic derivation of stapes ?
A
reicherts bar - 2nd pharyngeal arch
10
Q
What are the 4 parts of the temporal bone ?
A
petromastoid part
squamous part
tympanic ring
styloid process
11
Q
What is contained in the petromastoid portion ?
A
middle and inner ear
12
Q
Where is the tympanic ring ?
A
the external part of the ext.auditory tibe
13
Q
What are the formaina in the temporal bone ?
A
jugular fo carotid canal stylomastoid fo internal auditory meatus greater and lesser petrosal hiatus
14
Q
What are the 4 walls of the middle ear ?
A
anterior
posterior
lateral
medial
15
Q
What are the 2 openings on the anterior wall ?
A
pharyngotympanic tube - bigger
opening for the tensor tympani
16
Q
What are the features of the medial wall of middle ear ?
A
promantory - formed from the undelrying cochlea
round window
oval window
17
Q
Which opening is occupied by the footplate of the stapes ?
A
oval window (fenestra vestibuli)
18
Q
What are the features of the posterior wall of the middle ear ?
A
the pyramid - contains the stapedius - attached the Stapes
19
Q
What are the features of the lateral wall of the middle ear ?
A
tympanic membrane and the epitympanic recess
20
Q
What are the features of the malleus ?
A
Consists of a round head in the epitympanic recess
long process in the tympanic membrane
facet for the incus
21
Q
Where does the tensor tympani insert ?
A
into the long process (manubrium) of the malleus
22
Q
What are the features of the incus ?
A
long process
short process
facets for malleus and incus
23
Q
What are the features of the stapes ?
A
head - facet for the incus
arch and flat oval base which occupies the oval window
24
Q
Where does the stapedius muscle insert ?
A
tendon for the stapedius muscle inserts into the neck of the stapes
25
How do the ossicles enable us to hear ?
sound is funneled by the auricle and the external auditory meatus.
increases air pressure over the tympanic membrane
manubrium moves medially
head moves in antero-posterior direction
base of stapes pushes on the oval window
26
What are the functions of the ossicles ?
act as an impedance matching device
apply pressure to the oval window
work in a lever action
protect against loud sounds
27
What are the functions of tensor tympani and stapedius ?
modulate the frequency response
| protect against loud sounds
28
The facial nerve leaves the brainstem as which 2 branches ?
nervus intermedius
| motor root
29
How do the 2 roots enter the skull ?
they fuse and enter the petrous temporal bone through the internal auditory meatus
30
What does the facial nerve do in the petrous temporal bone ?
it travels in the facial canal
| and bends at the epitympanic recess to give the geniculate ganglion
31
What are the branches of the geniculate ganglion ?
greater petrosal nerve
32
What does the greater petrosal nerve do ?
contains parasympathetic secretomotor axons to the pterygopalatine ganglion
33
What does the pterygopalatine ganglion supply ?
nasal lacrimal and palatine mucous glands
34
What does the greater petrosal nerve do ?
travels in the hiatus of the greater petrosal nerve and joins the deep petrosal nerve to form the nerve of the pterygoid canal which enters the pterygopalatine fossa
35
What is the deep petrosal nerve a branch of ?
the superior cervical ganglion
36
What is the lesser petrosal nerve a branch of ?
glossopharyngeal
37
What does the lesser petrosal nerve do ?
joined by the tympanic branch of the IX to supply parasympathetic secretomotor axons to the parotid gland
38
What joins the lesser petrosal nerve at the tympanic plexus ?
a small branch from the geniculate ganglion joins the LPN at the promantory
39
How does the lesser petrosal nerve travel ?
in the petrous temporal bone and emerges at the hiatus of the lesser petrosal nerve to enter the FO.Ovale to provide preganglionic axons to the otic ganglion
40
Where does the nerve to stapedius emerge ?
arises distal to the geniculate ganglion and travels to stapedius
41
Where is the chorda tympani given off ?
in the petrous temporal bone
42
Where does the chorda tympani pass ?
over the tympanic membrane and ossicles to the infratemporal fossa
joins the lingual nerve
43
How does the chorda tympani enter the infratemporal fossa ?
through the petrotympanic fissure
44
What does the chorda tympani contain ?
parasympathetic preganglionic secretomotor axons to the submandibular ganglion
taste fibres for the anterior two thirds of the tongue
45
Where does the facial nerve emerge from the skull ?
the stylomastoid foramen
46
What branches does the facial nerve give off before passing into the parotid gland ?
branches to Post. Digastric and Stylohyoid
47
What does the facial nerve do in the parotid gland ?
gives off the temporal , zygomatic , buccal , mandibular and cervical branches to the muscles of facial expression
48
What does the inner ear do ?
concerned with reception of sound and balance
49
Where is the inner ear found ?
medial to the middle ear in the petrous temporal bone
50
What does the inner ear consist of ?
bony (osseous) labyrinth and a membranous labyrinth
51
What is the bony labyrinth ?
an interconnecting system of twisted canals filled with peri-lymph
52
What does the bony labyrinth do ?
consists of the vestibule , cochlea and the semilunar canals
53
What does the vestibule do ?
communicates with the round and oval windows
54
What is the cochlea ?
hearing organ
55
What are the semi-lunar canals ?
anterior , posterior and lateral
56
What is the membranous labyrinth ?
suspended in peri-lymph
57
What is the superior margin of the orbit made of ?
orbital plate of the frontal bone
58
What are the lateral margins of the orbit made of ?
zygomatic bone
59
What are the inferior margins of the orbit made of ?
zygomatic bone and maxilla
60
What are the medial margins of the orbit made of ?
frontal process of the maxilla and posteriorly the lacrimal bone
61
Which bone is the optic canal in ?
lesser wing of sphenoid
62
What does the optic canal transmit ?
optic nerve and the opthalmic artery
63
What is the superior orbital fissure ?
a cleft between the greater and lesser wings of sphenoid
64
What structures are transmitted by the superior orbital fissure ?
```
lacrimal nerve
frontal nerve
trochlear nerve
superior oculomotor
nasociliary
inferior oculomotor
abducent
```
65
What is the inferior orbital fissure a cleft between ?
the greater wing of sphenoid
| maxilla
66
What does the inferior orbital fissure transmit ?
opthalmic vein
| orbital branch of the middle meningeal
67
What do the anterior and posterior ethmoidal foramina do ?
transmit the anterior and posterior ethmoidal nerves to the ethmoidal air sinuses
68
What are the attachments of levator palpebrae superioris ?
attaches to the roof of the orbit and the skin of the upper eyelid
69
What is the action of LPS ?
elevation of the upper eyelid
70
What muscle opposes the action of LPS ?
orbicularis oculi
71
What is the innervation of LPS ?
oculomotor
72
What are the attachments of superior rectus ?
arises from the tendinous ring and and inserts into the superior aspect of the eyeball
73
What are the actions of superior rectus ?
elevation
adduction
inward rotation at extreme adduction
74
What is the innervation of superior rectus ?
oculomotor
75
What are the attachments of inferior rectus ?
Arises from the tendinous ring and inserts into the posteroinferior aspect of the eyeball
76
What are the actions of inferior rectus ?
depression
adduction - towards the midline
outward rotation at extreme adduction
77
What is the innervation of inferior rectus ?
oculomotor
78
What are the attachments of lateral rectus ?
Arises from the tendinous ring and inserts into the lateral aspect of the eyeball
79
What are the actions of lateral rectus ?
abduction - away from the midline
80
What is the innervation of lateral rectus ?
abducens
81
What is the attachments of superior oblique ?
Doesn't arise from the common tendinous ring - comes from a tendon above the common tendinous ring
passes through the trochlea
inserts into superoposterolateral aspect of eyeball
82
What are the actions of superior oblique ?
depression
abduction
inward rotation at extreme abduction
83
What is the innervation of superior oblique ?
trochlear
84
What are the attachments of inferior oblique ?
arises from the floor of the orbit and inserts into the psoteroinferolateral aspect of they eyeball
85
What are the actions of inferior oblique ?
elevation
abduction
outward rotation at extreme abduction
86
What is the innervation of inferior oblique ?
oculomotor
87
What are the 3 terminal branches of the opthalmic divsion of the trigeminal ?
nasociliary
lacrimal
frontal
88
What does the lacrimal nerve do ?
passes to the lateral wall of the orbit and picks up postsynaptic fibres from the pterygopalatine ganglion and the zygomatic nerve.
goes to the lacrimal gland
89
What does the frontal nerve do ?
It lies on LPS and divides into the supraorbital and the supratrochlear nerves
90
How does the nasociliary nerve pass ?
passes anteromedially
91
What are the branches of the nasociliary nerve ?
```
ganglionic branches
long ciliary nerve
posterior ethmoidal nerve
infratrochlear nerve
anterior ethmoidal nerve
```
92
What are the terminal branches of the nasociliairy nerve ?
infratrochlear and anterior ethmoidal nerves
93
What does the anterior ethmoidal nerve do ?
supply the anterior ethmoidal cells
| emerges as the external nasal nerve
94
What are the 3 coats of the eyeball ?
fibrous coat
vascular coat
neural coat
95
What does the fibrous coat consist of ?
sclera and the cornea
96
What does the vascular coat consist of ?
choroid- venous/arterial
ciliary body- suspends the lens via the suspensory ligament and contains the ciliary muscle
iris
97
What are the muscles found in the irris ?
constrictor pupillae
| dilator pupillae
98
What is the innervation of the constrictor pupillae ?
parasympathetic fibres of Oculomotor - from ciliary ganglion
99
What is the innervation of dilator pupillae ?
sympathetic fibres
100
What does the neural coat consist of ?
nervous layer - macula
101
What is the lacrimal gland ?
a serous gland wrapped around the free border of the LPS creating 2 lobes
102
How do tears wash over the eyelid and where do they go ?
tears drain medially and into the lacrimal sac and then the nasolacrimal duct and the inferior meatus
103
Where does the parasympathetic supply to the lacrimal gland come from ?
from the pterygopalatine ganglion
the greater petrosal nerve and the deep petrosal nerve fuse to form the nerve of the pterygoid canal. Postganglionuc fibres enter the orbit though the inferior orbital fissure as the zygomatic nerve
104
Where does the zygomatic nerve pass ?
through the inferior orbital fissure
105
What does the ciliary ganglion do ?
provides innervation to the dilator and constrictor pupillae
106
What is the parasympathetic root of the ciliary ganglion ?
from the oculomotor nerve to the constrictor pupillae
107
What is the sympathetic root of the ciliary ganglion ?
arises from the internal carotid and opthalmic artery plexus and supplies the dilator pupilale muscle
108
What is the sensory root of the ciliary ganglion ?
from the nasociliary nerve and the iris and the cornea and the long ciliary nerves
109
What are the branches of distribution of the ciliary ganglion ?
short ciliary nerves
110
What is intramembranous ossification ?
mesoderm to bone
111
What is endochondral ossification ?
cartilage to bone
112
How does the cranial vault form ?
intramembraneous ossification
113
How does the cranial base form ?
endochondral ossification
114
What is the boundary between the anterior and middle cranial fossa ?
lesser wings of sphenoid
anterior clinoid processes
jugum sphenoidale
115
What are the boundary between the middle and posterior cranial fossae ?
superior border of the petrous temporal bone
posterior clinoid processes
dorsum sellae
116
What are the features of the anterior cranial fossa ?
crista galli
cribriform plate
orbital plate of frontal bone
117
What are the features of the middle cranial fossa ?
```
Jugum sphenoidale
sella turcica
pituitary fossa
optic canal
Fo. Lacerum
Superior orbital fissure
Fo.Rotundum
Fo. Ovale
Fo.Spinosum
Hiatus for the greater and lesser petrosal nerves
```
118
What are the features of the posterior clinoid fossa ?
```
Clivus
Fo. Magnum
Hypoglossal canal
jugular Fo
Internal auditory meatus
Internal occipital protuberance
```
119
Which cranial nerves emerge in the anterior cranial fossa ?
olfactory
120
Which cranial nerves emerge in the middle cranial fossa ?
```
optic
oculomotor
trochlear
trigeminal
abducens
```
121
Which cranial nerves emerge from the posterior cranial fossa ?
```
Facial
vestibulocochlear
glossopharyngeal
vagus
spinal accessory
hypoglossal
```
122
What are the 3 layers of the meninges ?
dura mater
arachnoid mater
pia mater
123
What are the 4 parts of the dura mater ?
falx cerebri
falx cerebelli
diaphragma sella
tentorium cerebelli
124
What does the falx cerebri do ?
hangs down into the cranial cavity and separates the 2 cerebral hemispheres
125
What does the falx cerebelli do ?
separates the right and left cerebellar hemispheres
126
What is the diaphragma sellae do ?
a small fold between the anterior and posterior clinoid processes
127
What are the 2 spaces between the meningeal layers ?
extradural space
| subarachnoid space
128
What is the extradural space ?
space between the dura and the bone
129
What is the subarachnoid space ?
below the arachnoid mater and is filled with CSF
130
Do venous sinuses contain valves?
no
131
What do the dural venous sinuses do ?
drain blood from the brain into the internal jugular vein and the jugualr foramen
132
What does the superior sagittal sinus drain into ?
the confluence
133
What does the inferior sagittal sinus do ?
turns into the straight sinus as it approaches the tentorium cerebelli
134
What is the transverse sinus ?
passes laterally from the confluence and becomes the sigmoid sinus as it passes to the petrous temporal bone
135
What is the sigmoid sinus ?
continues medially from the petrous ridge to the jugular fo. All blood drains into the sigmoid sinus
136
What are the cavernous sinuses ?
lie in the body of the sphenoid on either side of the sella tursica - draineed by the superior and inferior petrosal sinuses
137
What does the superior petrosal sinus do ?
drains into the cavernous sinus
138
What does the inferior petrosal sinus do ?
drains directly into the internal jugular vein
139
What is the arterial supply of the brain ?
vertebral and the internal carotid arteries
140
How does the internal carotid artery enter the posterior cranial fossa ?
through the carotid canal
141
How does the vertebral artery enter the posterior cranial fossa ?
foramen magnum
142
What are the structural buttresses of the skull ?
ares of bone that are the most structurally stable and are the least likely to break
143
What does the buttress system do ?
absorbs and transmits forces applied to the facial skeleton to protect fragile bony areas
144
What does the CSF do ?
supports the brain and absorbs the energy of impact
145
What do the dural reflections do ?
support the brain and transmit the wieght of the rbain to the skull
146
What do the dural venous sinuses do ?
involved in temperature regulation by cooling arterial blood and protects against transient changes in venous pressure
147
What are the 4 types of haemorrhages ?
extradural
subarachnoid
subdural
intracerebral
148
What are extradural haemorrhages ?
between the dura mater and the bone - rupturing of the middle meningeal artery
149
What are subdural haemorrhages ?
bleeding into the subdural space - rupturing of the superior cerebral veins
150
What are subarachnoid haemorrhages ?
bleeding into the subarachnoid space such as aneurysms and angiomas
151
What are intracerebral haemorrhages ?
bleeding into the brain itself - eg . middle cerebral artery
152
What are typical routes of infection spread ?
tissue planes
venous
lymphatic
direct erosion
153
What are some of the spaces that infection either intraoral or extraoral can spread to from a 3rd man molar ?
```
sublingual space
submental space
submandibular space
pterygomandibular space
peritonsillar space
parotid space
```
154
Describe the route of infection spread from a 3rd mandibular molar ?
periapical abcess - in the roots of molar
breaks through on the lingual side
enters the sublingual space
spread backward - ludwigs angina
155
What can infections erode ?
basiocciput
| enter the mediastinum
156
What is the second route of infection spread ?
from submandibular space
into lateral pharyngeal space
retropharyngeal space
157
What are the severe consequences of infection if left untreated ?
airways obstruction
intracranial spread
septicaemia
158
Describe a route of infection spread from the cavernous sinus ?
from the cavernous sinus into the emissary veins and the into the infraorbital vein into the facial vein
159
Describe a second route of infection from the cavernous sinus ?
from the cavernous sinus into the pterygoid plexus of veins and into the RM vein
160
What bones does the orbital plate of the zygomatic bone articulate with ?
frontal bone
zygomatic process of the temporal bone
maxilla
greater wing of sphenoid
161
Name the foramina located in the greater wing of sphenoid ?
foramen ovale , rotundum and spinosum
162
What bones does the maxilla articulate with ?
```
zygomatic bone
palatine bone
ethmoid bone
inferior concha
frontal bone
lacrimal bone
nasal bone
```
163
Which extraocular muscles dont arise from the common tendinous ring ?
LPS and superior oblique
164
Why does swallowing help reduce pressure difference?
pain develops on either side of the tympanic membrane
swallowing is accompanied by contraction of salpingopharyngeus
this opens the auditory tube
equalises the pressure on either side of the tympanic membrane
165
What are the functions of the mandibular division of the trigeminal nerve ?
```
motor to the muscles of mastication
tensor veli palatini
tensor tympani
anterior belly of digastric
mylohyoid.
Sensory to the skin over the cheek and parotid gland and the lingual gingivae
```
166
What does the superior sagittal sinus drain into ?
transverse sinus and the confluence of sinuses
167
Where is the cavernous sinus located ?
in a groove in the body of sphenoid
168
What artery passes medial to the cavernous sinus ?
internal carotid artery
169
Which cranial nerves run close to the internal carotid artery ?
```
oculomotor
abducens
opthalmic
maxillary
trochlear
```
170
What would damage to the facial nerve cause ?
facial paralysis
loss of taste sensation in the anterior 2/3 of the tongue
loss of the stapedius relfex
loss of lacrimal gland secretion
171
Between which meningeal layers does CSF flow ?
between the arachnoid and the pia mater
172
What are the roles of the CSF ?
transmit some of the weight of the brain to the skull
| shock absorber
173
What do the posterior ethmoidal air cells drain into ?
superior meatus
174
Where does the frontal sinus drain into ?
superior meatus
175
What blood vessels does the superior orbital fissure transmit ?
orbital branch of the middle meningeal
| superior opthalmic vein
176
What are the boundaries between the anterior and middle cranial fossa ?
lesser wings of sphenoid
anterior clinoid prcoesses
jugum sphenoidale
177
What are the boundaries between the middle and posterior cranial fossa ?
superior borders of the petrous ridge
posterior clinoid processes
dorsum sellae
178
What bones forms the floor of the middle cranial fossa ?
temporal and sphenoid
179
What is medial to the cavernous sinus ?
internal carootid artery
| abducnets
180
What is lateral to the cavernous sinus ?
oculomotor
trochlear
opthalmic
v2
181
What is superior to the tentorium cerebelli ?
occipital lobe
| cerebellum
182
What is inferior to the tentorium cerebelli ?
brainstem
183
What are the 4 types of intracranial haemorrhage ?
extra dural
sub dural
sub arachnoid
intra cerebral
184
What forms the superior margin of the orbit ?
orbital plate of the frontal bone
| lesser win og sphenoid
185
What forms the inferior margin of the orbit ?
orbital plate of the maxilla
zygomatic bone
small part of paaltine bone
186
What forms the medial margin of the orbit ?
lacrimal bone
ethmoid bone
body of sphenoid
187
What is the posterior wall of the orbit made from ?
body and greater wing of sphenoid
188
What is the action of LPS ?
closes the upper eyelid
189
What is the action of superior rectus ?
Elevation
adduction
inward rotation at extreme adduction
190
What is the action of inferior oblique ?
Elevation
abduction
outward rotation at extreme abduction
191
What is the action of superior oblique ?
depression
abduction
inward rotation at extreme abduction
192
What is the action of superior oblique ?
depression
abduction
inward rotation at extreme abduction
193
What is the action of laterla rectus ?
abduction
194
What is the action of superior rectus ?
elevation
adduction
inward rotation at extreme adduction
195
What is the action of inferior rectus ?
deprssion
adduction
outward rotation at extreme adduction
196
Which of the branches of V1 is medial ?
nasocilairy
197
Obliques tend to ?
abduct
198
Rectuses tend to ?
adduct except LR- abduction
199
How can infection spread to the cranium from a maxillary canine ?
erode maxilla
superior opthalmic vein
cavernous sinus
200
What do the parasympathetic postganglionic axons of the ciliairy ganglion supply ?
constrictor pupillae
| ciliary muscle- alter the shape of the lens
