ANATOMY - Head part 2 Flashcards
1
Q
embryological origin pons
A
embryonic metencephalon
2
Q
what structure separates the pons and the cerebellum posteriorly
A
4th ventricle
3
Q
what structure is inferior to the pons
A
medulla oblongata
4
Q
what structure is superior to the pons
A
midbrain
5
Q
what is the pontomedullary junction
A
angle between the lower border of the pons and the superior border of the medulla
6
Q
which 4 cranial nerves originate from the ventral pons surface
A
V
VI
VII
VIII
7
Q
draw circle of Willis
A
8
Q
where are the lateral ventricles of the brain
A
located within the hemispheres of the cerebrum
9
Q
where do the horns of the lateral ventricles project into
A
frontal, occipital and temporal lobes
10
Q
what happens to the volume of the lateral ventricles with age
A
increases
11
Q
lateral ventricles drain into the 3rd ventricles via
A
Foramen of monroe
12
Q
where are the 3rd ventricles
A
between the R+L thalamus
13
Q
what are the 3 protrusions on the anterior surface of the 3rd ventricle
A
supra-optic recess (above optic chiasm)
infundibular recess (above optic stalk)
14
Q
what connects the 3rd and 4th ventricles
A
cerebral aqueducts
15
Q
where is the 4th ventricles?
A
within brainstem at jct pons of medulla
16
Q
names of the lateral and medial foramen connecting the 4th ventricle to the subarachnoid space
A
foramen of Magendie (medial)
foramen of Lushka (lateral)
17
Q
what 2 spaces does the 4th ventricle drain into
A
central spinal canal (bathes SC)
sub-arachnoid cisterns (baths brain between arachnoid + pia)
18
Q
where is CSF reabsorbed back into the circulation?
A
at the subarachnoid cisterns (then via the dural venous sinuses)
19
Q
what is CSF produced. by
A
choroid plexus
20
Q
what is the choroid plexus
A
capillaries + loose CT, surrounded by cuboid epithelial cells
21
Q
what 2 paired arteries make up the circle of Willis
A
vertebral and ICA
22
Q
what spinal level does the ICA originate from
A
C4
23
Q
what structure does the ICA move upwards in to entry the brain ?
A
carotid sheath
24
Q
where is the carotid canal
A
in the temporal bone of the middle crfanial fossa
25
before giving rise to its branches in the cranial cavity, through which area does the ICA pass anteriorly through?
cavernous sinus
26
4 branches of the ICA in the cranium
ophthlamic aa
post communicating aa
ant choroidal aa
ant cerebral aa
27
post communicating aa supplies
connects vessels in circle of willis
28
ant choroidal aa supplies
brain structures important for vision + motor control
29
what aa does the ICA continue as
middle cerebral aa
30
origin of the vertebral aa
SCA, medial to the anterior scalene
31
how does the vertebral aa travel up the spine
through foramen strasversarium of the transverse processes of the C spine
32
via which foramen do the vertebral aa enter the cranium
foramen magnum
33
after the foramen magnum, what 3 branches does the vertebral aa give rise to
meningeal branch (falx cerebelli)
ant/post spinal aa
post infer cerebellar aa
34
after giving off its branches in the brain, what do the vertebral aa converge to become
basillar aa
35
anterior cerebral aa supplies
anteromedial part of the cerebellum
36
middle cerebral aa supplies
lateral part of the brain
37
posterior cerebral aa supplies
medial/lateral post parts of the brain
38
where do the posterior spinal aa anastomose with eachother
pia mater
39
aa supplying the spinal cord
ant + post spinal aa (^ vertebral aa)
also support via the segmental + radicular aa
40
where does the dural vv drainage of the brain lie?
between the periosteal + meningeal layers of the duramater
41
does the dural venous system have valves?
no
42
how many veins make up the dural venous system?
11
43
drainage of dural venous system to the IJV
straight, sup saggital + inf saggital converge at the confluence
--> transverse --> sigmoid --> IJV
44
journey of venous blood from the cerebrum to the dural venous sinuses
superficial and deep systems --> exit parenchyma --> SA space --> pierce meninges --> dural sinuses
45
what are the 5 main vv in the superficial cerebrum system
sup cerebral vv
sup middle cerebral vv
inf cerebral cc
sup anastomotic vv of Trolard
Inf anastomotic vv of Labbe
46
what does the sup anastomotic vv of Trolard connect?
sup middle cerebral vv to sup saggital sinus
47
what does the inf anastomotic vv of Labbe connect
connects sup middle cerebral vv to transverse sinus
48
what are the deep vv system of the cerebrum (2)
subependymal vv + medullary vv
49
vv drainage of the cerebellum
sup + inf cerebellar vv --> sup petrosal, transverse + straight sinuses
50
vv drainage spinal cord
3 x ant + 3 x post spinal vv --> form anastomotic network along spinal cord --> vertebral plexus --> systemic segmental vv
51
name of glands which secrete ear wax
ceruminous glads
52
blood supply to the ext auditory canal
auricotemporal branch of the sup temporal aa
post auricular branch of eca
53
sensory inn ext auditory canal
auricotemporal branch of CN X
54
which bone is the middle ear within>
temporal
55
inn of the tympanic membrane
auricotemporal + auricular branch of CN X
56
what is the name of the weakest point of the tympanic membrane
pars flaccida
57
what pathology can occur in the pars flaccida of the ear?
cholesteatoma
58
what is the largest ossicle of the ear
malleus
59
what part of the malleus is attached to the tympanic membrane?
lateral process
60
what part of the incus is associated with the malleus
body
61
what part of the stapes is associated with the incus
head
62
which 2 muscles are attached to the ossicles?
tensor tympani
stapedius
63
which 2 nerves run through the middle ear
chorda tympani
facial nn
64
what bone is the inner ear in?
petrous part temporal bone
65
base of cochlear transmits..
low frequency sounds
66
apex of cochlear transmis ...
high frequency sounds
67
where is the pterygopalatine fossa?
from infratemporal fossa to nasal cavity
betewen the maxilla, phenoid + palatine bone
68
borders pterygopalatine fossa
ant - post wall maxillary sinus
post - pterygoid process sphenoid bone
inf - palatine bone, palatine canals
sup - inf orbital fissure
med - perpendicular plate palatine bone
lat - pteryogmaxillary process
69
nn contents ptergopalatine fossa
CN V2 + here it branches:
infraorbital nn
zygomatic nn
nasopalatine nn
sup alveolar nn
pharyngeal nn
greater/lesser palatine nn
70
through which foramen for CN V2 enter into the ptergopalatine fossa?
foramen rotundum
71
what is the predominant innervation of the pterygopalatine ganglion
greater petrosal branch of CN VII
72
name the 7 foramina of the ptergopalatine fossa
pterogmaxillary fissure
foramen rotundum
2 x pterygoid + pharyngeal arches
infra orbital fissure
greater palatine canal
sphenopalatine foramen
73
contents pterygomaxillary fissur e(2)
post sup alveolar nn
maxillary aa
74
pterygoid canal transmits aa/vv/nn from the pterygopalatine fossa to the
nasopharynx
75
pharyngeal canal transmits the pharyngel branch of CN V2 to the
nasopharynx
76
contents of infraorbital fissure (3)
zygomatic branch CN V2
infra orbital aa/vv
to the orbit, lacrimal gland + eye mm
77
greater palatine canal tranmits aa/vv/nn from the ptergopalatine fossa to the
oral cavity - hard and soft palate
78
contents of the greater palatine canal (4)
descending palatine aa
descending palatine vv
greater palatine nn
lesser palatine nn
79
sphenopalatine formaen transmits aa/vv/nn from the pterygopalatine fossa to the
nasal cavity
80
contents sphenopalatine foramen (3)
sphenopalatine aa
sphenopalatine vv
nasopalatine nn
81
where is the infratemporal fossa
at the base of the skull, deep to the masseter muscle and zygomatic arch
82
shape of infratemporal fossa
wedge shaped
83
boundaries of the infratemporal fossa
lateral: condylar process + ramus mandible
medial: lat pterygoid plate, TVP, TLP, sup constrictor mm
anterior: post border maxillary sinus
post: carotid sheath
roof: greater wing sphenoid - prov passageways to the foramen ovale + spinosum
floor: medial pterygoid
84
contents infratemporal foramen (8)
mm mastication specifically the pterygoids
CN V3 + branches - auricotemporal, buccal, lingual, inf anveolar
chorda tympani (follows lingual nn)
otic ganglion (hitchhikes along auricotemporal to parotid)
maxillary aa
pteerygoid vv plexus
maxillary vv
middle mengingeal vv
85
what does the maxillary aa branch into in the infratemporal fossa?
MMA (then goes through foramen spinosum)
86
where is the mastoid fossa?
triangular shape depression in the external surface of the temporal bone
87
borders of the mastoid fossa
sup: supramastoid crest (extension of the zygomatic process)
ant: suprameatal spine of henle
post: hypothetical vertical line at the midpoint of the post border of the ext auditory canal
88
contents mastoid fossa
NOTHING except mastoid air cells
89
importance mastoid fossa
safe zone in mastoidectomy to start drilling
90
where is the cavernous sinus?
within the middle cranial fossa, eitherside of the sella turcica of the sphenoid
91
borders of the cavernous sinus
roof: meningeal layer attaching to ant + middle clinoid process sphenoid
ant - sup orbital fissure
post - petrous part temporal bone
medial - body sphenoid
lateral - meningeal layer dura mater of middle cranial fossa
floor - endosteal layer dura mater overlying greater wing sphenoid
92
structures travelling through the cavernous sinus (3)
CN VI
carotid plexus
ICA
93
structures travelling through lateral wall cavernous sinus (4)
CN III
CN IV
CN V1
CN V2
94
what is cavernous sinus thrombosis
clot within cavernous sinus
95
what is cavernous sinus thrombosis usually due to
infection
96
Sx cavernous sinus thrombosis
periorbital oedema
CN VI palsy
97
Tx cavernous sinus thrombosis
ABx
98
which vv does each dural venous sinus receive blood form (5)
ophthalmic vv
central vv retina
spenparietal sinus
superficial middle cerberal vv
pterygoid plexus
99
route of cavernous vv sinus to IJV
cavernous sinus --> sup + inf petrosal sinus --> IJV
