1. Neuroanatomy Flashcards
1
Q
How to distinguish ICA and ECA in the neck?
A
ECA has multiple branches in the neck
2
Q
Major Branches of ECA
A
SALFOPSI Superior thyroid Ascending pharyngeal Lingual Facial Occipital Posterior auricular Superficial temporal Internal maxillary
3
Q
Where do common carotid arteries arise?
A
Right: brachiocephalic trunk
Left: aortic arch
Bovine arch vs true cattle arch (which is very rare)
Matters when trying to catheterize left common carotid
4
Q
What is the carotid siphon?
A
Intracavernous and supraclinoid segment of ICA
5
Q
Findings in occlusion of anterior choroidal artery?
A
Hemiparesis, hemianesthesia, hemiopsia
6
Q
Posterior cerebral artery divides into which two arteries?
A
Parietooccipital and Calcarine aa
7
Q
What artery supplies the choroid plexus of temporal horn?
A
Posterior cerebral artery gives rise to posterior choroidal arteries, anastamose with anterior choroidal arteries
8
Q
Virchow-Robin spaces
A
Spaces between blood vessels and arachnoid/pia within brain and spinal cord, perivascular spaces
9
Q
Which large anastomotic vein joins the superior sagittal sinus?
A
Vein of Trolard
10
Q
Which large anastomotic vein joins veins of sylvian fissure with transverse sinus
A
Vein of Labbe
11
Q
What is the largest branch of the intracavernous portion of carotid artery?
A
Meningohypophyseal trunk
12
Q
Three main superficial cerebral veins
A
Vein of Trolard
Vein of Labbe
Superficial middle cerebral vein
13
Q
Clinical symptom of large unruptured cavernous sinus carotid aneurysm
A
Ipsilateral 6th nerve palsy (most proximal spatial relationship to carotid artery)
14
Q
Wallenberg syndrome (lateral medullary syndrome) - artery
A
Occlusion of ipsilateral vertebral artery. Infarct supplied by PICA
15
Q
What artery supply the thalamus?
A
Posterior communicating and perimesencephalic portion of posterior cerebral artery
16
Q
What artery supply the lateral geniculate nucleus?
A
Anterior choroidal and lateral posterior choroidal (dual supply)
17
Q
Artery involved in trigeminal neuralgia
A
SCA
18
Q
Artery involved in hemifacial spasm
A
AICA
19
Q
Artery involved in glossopharyngeal neuralgia
A
PICA
20
Q
Artery supply of internal capsule
A
Lateral lenticulostriate branches from MCA
Medial striate from ACA (Huebner)
Direct branch from ICA
21
Q
Which vessel has highest risk of injury in Chiari decompression surgery?
A
PICA
22
Q
Vessels supply superior, middle, and inferior cerebellar peduncles?
A
SCA, AICA and PICA respectively
23
Q
Where is motor strip in relation to the skull?
A
~5 cm behind coronal suture
24
Q
What external landmark on skull marks the lateral margin of sphenoid ridge and sylvian fissure?
A
Pterion, confluence of frontal, parietal, squamous temporal, and greater wing of the sphenoid bones in the skull
25
What part of mandible does the temporalis muscle attaches to?
Coronoid process of mandible
26
Which muscle of mastication does the parotid duct cross
Masseter muscle
27
Which cranial fossa is the largest and deepest?
Posterior
28
Suboccipital triangle bounded by which 3 muscles?
Rectus capitis posterior major
Superior oblique
Inferior oblique
29
What sutures make up the asterion?
Lambdoid, parietomastoid, occipitaomastoid
It defines lower half of junction of transverse and sigmoid sinuses
Adult, 4cm posterior and 12mm superior to ear canal
30
Which bones make up the osseous nasal septum?
Ethmoid and vomer
31
Compartments of jugular foramen
Pars venosa (posterolateral): sigmoid sinus, jugular bulb, CN X, XI
Pars nervosa (anteromedial): CN IX and Jacobson's nerve (tympanic branch of IX)
32
What structure does abducens nerve go through to enter the cavernous sinus?
Dorello's canal
33
What structures go through internal acoustic meatus
CNVII (facial), CNVIII (vestibulocochlear) and labyrinthine artery (internal auditory)
34
Major parts of temporal bone
Squamous and petrous parts
35
cribriform plate is part of what bone?
Ethmoid bone
36
What goes through the jugular foramen?
Nerves: CNIX (glossopharyngeal), CNX (vagus), CN XI (accessory)
Artery: posterior meningeal artery
Vein: internal jugular vein
Sinus: inferior petrosal sinus
37
What are the bones that form the orbit?
```
Frontal
Sphenoid
Zygomatic
Ethmoid
Lacrimal
Maxilla
Palatine
```
38
What structures pass through the annulus of zinn?
Tendinous ring of 4 rectus muscle
CNII (Optic), CNIII (Oculomotor), CNVI (Abducens), nasociliary nerve (branch of opthalmic V1 nerve)
Opthalmic artery
39
What pass through pterygopalatine fossa?
Maxillary artery
Maxillary nerve
Pterygopalatine ganglion
40
What bones make up the clivus
41
What pass through the inferior orbital fissure?
```
Infraorbital nerve (maxillary) - innervate lower eyelid/upper lip
Zygomatic nerve (maxillary) - skin over zygomatic/temporal bone (sensory)
```
42
What bones are approximated at pterion?
Frontal, parietal, temporal, sphenoid
43
What structure separates optic canal from superior orbital fissure?
Optic strut
44
5 parts of lateral ventricle?
```
Frontal horn
Temporal horn
Occipital horn
Body
Atrium
```
45
Choroid plexus and flocculus protrude from which foramen?
Foramen of Luschka
46
Which cranial nerve nuclei positioned in lateral recess near foramen of luschka?
Dorsal/ventral cochlear nuclei of CNVIII
47
Where is BBB absent?
```
Pineal gland
Subforniceal organ
Organum vasculosum of lamina terminalis
Median eminence of hypothalamus
Neurohypophysis (posterior pituitary)
Area postrema
Subcommissural organ
```
48
What forms lateral walls of frontal horns of lateral ventricle? Medial wall? Roof?
Caudate nucleus, septum pellucidum, corpus callosum
Caudate injury causes abulia and psychic akinesia, neglect, frontal
49
Outlet of 4th ventricle
2 lateral foramina of luschka
1 medial foramen of magendie
50
What separates chiasmatic cistern from interpeduncular cistern?
Liliequist membrane
51
Where do sympathetic fibers of head originate from?
Hypothalamus, Through brainstem and cervical spinal cord to T1-L2
52
Where in brain are cholinergic neurons found?
Basal nucleus of Meynert
53
Norepinephrine-containing neurons
Locus cereuleus
54
Sympathetic innervation to head and neck?
Stellate ganglion
55
What ganglions form the stellate ganglion
Inferior cervical ganglion fuse with first thoracic ganglion to form cervical thoracic (stellate) ganglion
56
Type of nerve fiber of vidian nerve
Parasympathetic fibers from greater superficial petrosal nerve (lacrimal nasal palatine glands)
Sympathetic fibers from deep petrosal nerve around ICA (sympathetic innervation to lacrimal, and blood vessels)
Nerve passes in the pterygoid canal with vidian artery
57
Type of nerve fiber of intermediate nerve (nervus intermedius)
Sensory and parasympathetic division of facial nerve
Preganglionic parasympathetic fiber from superior salivary nucleus that synapse in pterygopalatine and submandibular ganglia
Taste from anterior 2/3 of tongue
58
What provides the parasympathetics of parotid glands?
Glossopharyngeal nerve - originate from inferior salivatory nucleus and travels through CN IX -> synapse at otic ganglion -> parotid gland
59
What are leptomeninges?
Arachnoid and pia mater
60
What are pachymeninges
dura mater
61
How much CSF is produced each day
450mL
| ~150mL in average body at a time.
62
Brodmann's area for Broca
Area 44
63
Brodman's area for Wernicke
Area 22
64
Brodman's area for primary auditory cortex
Area 41
65
Which area of hippocampus is most vulnerable to hypoxia?
CA1 (Sommer's ector)
| CA3 is resistant
66
What is the indusium griseum?
Remnant of hippocampus that courses over the dorsal surface of corpus callosum (supracallosal gyrus) - medial and lateral longitudinal striae
67
What makes up the neostriatum?
Caudate and putamen
68
What white matter projects from Wernicke to Broca?
Arcuate fasciculus
69
Gustatory area receives input from which nucleus?
Ipsilateral nucleus solitarius
70
What is ischemic penumbra?
Decreased blood flow where neurons survive but not function. Gray matter require more blood supply than white matter
* prolonged (increased) T-max, typically >6 seconds (or other measures of delayed arrival of contrast such as mean transit time (MTT) or time to peak (TTP)), and...
*normal or increased cerebral blood volume (CBV) due to autoregulation
Mismatch ratio 1.8 or greater is common cutoff
Mismatch volume 10-15mL often cutoff
71
Lesion to right Meyer's loop
Left upper quadrantanopia
72
Lesion of posterior part of middle frontal gyrus
Cortical lateral conjugate gaze center - causes conjugate eye deviation toward ipsilateral side
73
Hypothalamus receives fibers from amygdala through which bundle?
Stria terminalis
74
Classic syndrome from dominant parietal lobe lesion
Gertsmann - agraphia without alexia, L/R confusion, finger agnosia, acalculia
inferior parietal lobule
75
Where is lesion for patient with hemineglect
Posterior parietal association cortex
Most often from lesion in nondominant lobe, i.e. right parietal lesion causes left hemispatial neglect
76
Where in internal capsule do corticobulbar fibers run
Genu
77
Where in internal capsule are corticospinal tract located
Posterior limb
78
Main neurotransmitter of corticothalamic tract
Glutamate
79
Satiety center
```
Medial hypothalamus VMH (stimulation causes decreased food intake)
Hunger in lateral LHA
```
80
Where is ADH made?
Supraoptic and paraventricular nuclei of hypothalamus
81
Which part of hypothalamus lowers body temperature
Anterior (stimulation causes dilation of blood vessels/sweating)
82
Where does corticospinal tract originates?
Layer 5 of cerebral cortex -> corona radiata -> posterior limb of internal capsule -> cerebral peduncles and pyramids of medulla -> lamina 7 in spinal cord
83
What makes up inferior parietal lobule
Angular and supramarginal gyri
| Parietal lobe is divided into superior and inferior lobules by the interparietal sulcus.
84
Prosopagnosia - which part is damaged?
Temporal association cortex - impairment in visual processing - recognize voice (auditory) but not recognize familiar faces
85
Papez circuit of the brain
hippocampus -> fornix -> mamillary bodies -> mammillothalamic tract -> anterior thalamic nucleus -> cingulate gyrus -> parahippocampal gyrus -> entorhinal gyrus -> hippocampus
86
Afferent fibers of pupillary light reflex cross the contralateral edinger-westfall nucleus through which structure?
Posterior commissure
87
Sensation from face - which thalamic nucleus
VPM (VPL for body)
M for Mandible
L for Leg
88
Which layer of cerebral cortex receives thalamocortical afferents?
Layer IV (internal granular)
89
Which layer of cerebral cortex has the main efferent neurons
V (internal pyramidal layer) - send axons through white matter to internal capsule
90
Layers of cerebral neocortex
I (molecular): most superficial, synaptic area
II (external granular): densely packed neurons
III (external pyramidal)
IV (internal granular): primary receiving station of cerebral cortex
V (internal pyramidal): send axon to internal capsule
VI (fusiform): primary origin of corticothalamic fibers
91
Primary reason for macular sparing in occipital cortex lesion
Macula has dual supply from MCA and PCA to occipital poles
92
Occipital (striate) cortex has dominance columns, except which 2 areas?
1. where blind spot is located
| 2. monocular temporal crescent of both eyes
93
of cortical layers of cerebellum
3
1. molecular
2. purkinje
3. granular
94
Only output cells of cerebellar cortex
Purkinje cells (inhibitory)
95
Cerebellar glomeruli consist of?
Mossy fibers stimulate granule cells
| Golgi type 2 cells inhibit them
96
Where do climbing fibers originate from
Contralateral inferior olive - cross to inferior cerebellar peduncle and ascend olecular layer -> stimulate dendrites of purkinje cells
97
Which cerebellar peduncle contains only afferent fibers
Middle
98
Another name for superior, middle and inferior peduncles
Brachium conjunctivum, brachium pontis, restiform body
99
Only afferent tract that runs through superior cerebellar peduncle
Ventral spinocerebellar tract (proprioceptive info to cerebellum from lower extremities/trunk)
100
2nd order neuron of olfactory
Mitral cells -> lateral olfactory area -> lateral/intermediate/medial olfactory areas
101
Pineal region tumor - syndrome
Parinaud syndrome: upper gaze palsy, dissociated light near response, retraction nystagmus, absence of convergence
102
Weber syndrome
CN3 palsy and contralateral hemiparesis. Infarct of medial midbrain.
103
Millard-Gubler syndrome lesion
At base of pons - 6/7 nerve palsy and contralateral hemiplegia
104
Function of red nucleus
Maintains flexor muscle tone
105
What are at level of midbrain
Red nucleus
pyramidal tract (corticonuclear/spinal fibers), oculomotor nerve
106
Input of red nucleus
Deep cerebellar nuclei and cerebral cortex
107
What are internal arcuate fibers
Crossing fibers of dorsal column fibers
Dorsal column (gracile fasciculus/cuneate) -> medulla synapse at nuclei -> migrate ventrally around central gray matter of medulla and cross midline -> ascend as medial lemniscus to reach VPL of thalamus.
108
Where is vertical gaze center
Rostral interstitial nucleus on medial longitudinal fasciculus, interstitial nucleus of Cajal INC, and posterior commissure nucleus, center gets input from FEFs and parietal lobes
109
Crossed nasal retinal visual fibers go to which layers of LGN
Layer 1,4,6
| Ipsilateral to 2,3,5
110
Which trigeminal nucleus receives pain/temp of face
Spinal trigeminal nucleus. Extends from ponds to C2 and merges caudally with substantia gelatinosa.
111
Which trigeminal nucleus receives prorioception from face
Mesencephalic nucleus
112
Lateral lemniscus carry?
2nd order neuron of auditory pathway -> ascends to inferior colliculus
113
Sensation from external auditory canal carried by vagus nerve arrives at which nucleus
Travel through Arnold's nerve to superior (jugular) ganglion of CN10 -> spinal trigeminal tract -> spinal trigeminal nucleus
114
General visceral sensation of vagus nerve arrives at which nucleus
Travel to inferior ganglion of 10 -> solitary tract to solitary nucleus in medulla.
115
Which CN most susceptible during carotid endarterectomy
CN11 (hypoglossal)
116
Hypoglossal nerve palsy in skull base tumor
Tumor infiltration into anterior portion of ipsilateral occipital condyle
117
Optic chiasm nml anatomic location?
Above diaphragma sellae
| May be prefixed and lie over tuberculum sellae or post fixed over dorsum sellae
118
Which CN carry general visceral efferent?
3, 7, 9, 10
119
Where does trochlear nerve decussate
Within superior medullary velum
120
What triggers a glossopharyngeal neuralgia attack?
Swallowing, talking, chewing
121
Hering's nerve
Branch of CN9 (sensory limb of carotid body)
| Detects changes in blood O2 and CO2 concentration
122
Digastric muscle innervation
Anterior - CN5
| Posterior - CN7
123
Which CNs pass through foramen magnum
Accessory
124
Unilateral vagal injury - symptoms
Hoarseness, dyspnea, dysphagia, ipsilateral decreased cough reflex, uvular deviation
125
Hypoglossal nerve innervates?
All intrinsic/extrinsic muscles of tongue except palatoglossus (CN10)
126
CN most often involved with tumors of upper cervical canal
Spinal accessory (torticollis/weakness of trapezius and SCM muscles)
127
Largest avascular organ in body
Intervertebral disk
128
Most common dermatome syndrome with craniocervical dx
C2
129
Where does pyramidal decussation begin and complete decussation?
Just below obex -> below exit of first cervical nerve root
130
Foramen magnum tumor with hand weakness - which spinal tract?
Cortical spinal tract
131
Enalrged intervertebral foramen on radiography
Nerve root tumor
132
What ligament important to divide for proper visualization of ventral spinal tumor after dural opening in posterior appraoch
Dentate ligament
133
Perioral tingling/numbness in syringobulbia is compression of which tract
Spinal trigeminal tract
134
Which ligament is primary restraint against atlantoaxial anteroposterior translation
Transverse ligament
135
What supplies sympathetic innervation to arm
T2 and T3 ganglia
136
Dorsal ramus of the C1 nerve root
Suboccipital nerve
137
What innervates cervical disk
Plexus formed by sinuvertebral nerve dorsally and plexus by cervical symp trunk ventrally
138
Level of aortic bifurcation
midbody of L3
139
What level spinal cord ends in adults
L1-L2
140
Loss of sensation over webspace of 1-2 toes
Injury to deep fibular nerve
141
Nerve root - loss of achilles reflex
S1
142
Nerve roots with biceps reflex
C5-C6
143
L5 nerve root - which reflex
None
144
Pain and temp first order neurons synapse?
-> DRG -> dorsolateral tract and synapse at substantia gelatinosa
145
XR of acute transverse myelitis
Usually normal; may have increased T2 weighted MR
146
Pott dx
Tuberculous vertebral osteomyelitis - affects body rather than disks
147
XR of infx vs tumor in spine
Destruction of disk space (infxn)
| Destruction of body and not cross disk space (tumor)
148
2 most common herniated disks
L4-L5
| L5-S1
149
Immunologically priviledged site of intervertebral disk
Nucleus pulposus - isolated from vascular/immune
150
Spurling/s sign
radicular pain when exert downward pressure on vertex while tilting head to symptomatic side - narrowing of intervertebral foramen
151
How do sympathetic fibers exit spinal cord
Ventral roots by white rami communicantes
152
Sensory loss in axillary nerve injury
Lateral aspect of shoulder
153
Posterior interosseous neuropathy - symptoms
Finger extension weakness including thumb with no wrist drop/sensory loss.
May be entrapped at arcade of Frohse (into supinator muscle)
154
Meralgia paresthetica
Bernhardt-Roth syndrome
Entrapment of lateral femoral cutaneous nerve of thigh - purely sensory nerve and compression causing burning dysesthesia in lateral upper thigh
155
Which muscle of thumb has dual innervation
Flexor pollicis brevis
| - median and ulner nerves
156
Site of entrapment of suprascapular nerve
Suprascapular notch beneath transverse scapular ligament
157
True neurogenic thoracic outlet syndrome - which nerve roots
C8 and T1
| Commonly due to cervical rib or elongated C7 transverse process
158
Symptoms of anterior interosseous syndrome
Weakness of flexion of distal phalanges of thumb, index, middle fingers - "pinch sign"
No sensory loss (pure motor branch of median nerve)
159
Wrist drop - what must be ruled out
Lead poisoning
160
Nociceptive vs neuropathic pain
Nociceptors: well localized pain, constant, aching or throbbing; time-limited usually, respond well to opioids
Neuropathic - longstanding, triggered by injury, infiltrative/tumor compression/scar strangulation/inflammation by infxn - burning, lancinating, electric shock qualities
161
Why is extensor carpi radialis muscle unique?
Innervated solely by C6 nerve root
162
Ligament of Struthers?
Present in small % of people
Crossing cubital fossa above medial intermuscular septum - can compress median nerve and mimic carpal tunnel.
Thenar numbness more pronounced
163
Arcade of Struthers
At elbow near medial head of triceps - may compress ulnar nerve
