Vasculature of Brain - Henkel - Exam 1

Question 1

Segments of Internal Carotid

• Cervical (extracranial) – ___
• Petrous – __
• Cavernous – __
• Supraclinoid– __

Answer 1

Segments:

• Cervical (extracranial) – C1
• Petrous – C2
• Cavernous – C3
• Supraclinoid– C4

Question 2

Segments/Relationships of Vertebral Artery:

• Prevertebral (V_)
• Cervical (V_)
• Suboccipital (V_)
• Posterior cranial fossa (V_) – supplies brainstem and cerebellum
• The left and right vertebral arteries merge to form the ___ artery completing formation of the posterior circulation to the brain

Answer 2

Segments/Relationships

• Prevertebral (V1)
• Cervical (V2)
• Suboccipital (V3)
• Posterior cranial fossa (V4) – supplies brainstem and cerebellum
• The left and right vertebral arteries merge to form the basilar artery completing formation of the posterior circulation to the brain

Question 3

Two types of strokes are:

_____ strokes are from inadequate blood supply to a region of the brain, often caused by thrombosis, embolism, or hypoxia.

The thrombotic type of ischemic stroke occurs when a ___ forms directly at the site of infarction, often over an ____ plaque. The most common location is the ___ ___ artery.

The embolic type of ischemic stroke occurs when an ____ from elsewhere in the body obstructs a cerebral vessel. This type of ischemic stroke can affect multiple cerebral vascular territories. This type is associated with cardiogenic causes and deep vein thrombosis (DVT) in the presence of a patent foramen ovale.

The hypoxic type of ischemic stroke is due to hypoperfusion or hypoxemia. This type tends to affect ____ areas and is common during cardiovascular surgical procedures.

Watershed areas/zones are areas of the brain between major ____ arteries, for example between anterior/middle cerebral arteries or middle/posterior cerebral arteries. Watershed infarcts can occur in these brain areas due to hypoxic ischemic stroke and often present with disturbances in visual processing with upper leg/arm weakness.

___ strokes occur due to rupture of cerebral blood vessel leading to intracerebral bleeding

Answer 3

Two types of strokes are:

Ischemic strokes are from inadequate blood supply to a region of the brain, often caused by thrombosis, embolism, or hypoxia.

The thrombotic type of ischemic stroke occurs when a clot forms directly at the site of infarction, often over an atherosclerotic plaque. The most common location is the middle cerebral artery.

The embolic type of ischemic stroke occurs when an clot from elsewhere in the body obstructs a cerebral vessel. This type of ischemic stroke can affect multiple cerebral vascular territories. This type is associated with cardiogenic causes and deep vein thrombosis (DVT) in the presence of a patent foramen ovale.

The hypoxic type of ischemic stroke is due to hypoperfusion or hypoxemia. This type tends to affect watershed areas and is common during cardiovascular surgical procedures.

Watershed areas/zones are areas of the brain between major cerebral arteries, for example between anterior/middle cerebral arteries or middle/posterior cerebral arteries. Watershed infarcts can occur in these brain areas due to hypoxic ischemic stroke and often present with disturbances in visual processing with upper leg/arm weakness.

Hemorrhagic strokes occur due to rupture of cerebral blood vessel leading to intracerebral bleeding

Question 4

Two sources of blood supply:

___ ____ system – gives major branches to lateral and medial surfaces of cerebral cortex and perforating arteries to deep cerebral nuclei

___ ____ system - supplies the brainstem, cerebellum, occipital cortex, inferior part of temporal lobe, and spinal cord

Answer 4

Two sources of blood supply:

Internal carotid system – gives major branches to lateral and medial surfaces of cerebral cortex and perforating arteries to deep cerebral nuclei

Vertebrobasilar system - supplies the brainstem, cerebellum, occipital cortex, inferior part of temporal lobe, and spinal cord

Question 5

The brain receives its blood supply from the ___ arteries and the ___ system which provide input to the Circle of Willis.

Answer 5

The brain receives its blood supply from the carotid arteries and the vertebrobasilar system which provide input to the Circle of Willis.

Question 6

The branches of the internal carotid artery is:

A VIP’S COMMA

Answer 6

A: anterior choroidal artery (C7)

V: Vidian artery (C2)

I: inferolateral trunk (C4)

P: posterior communicating artery (C7)

S: superior hypophyseal artery (C6)

C: caroticotympanic artery (C2)

O: ophthalmic artery (C6)

M: meningohypophyseal trunk (C4)

M: middle cerebral artery (C7)

A: anterior cerebral artery (C7)

Question 7

Superficial branches of the ____

Medial cortical branches supply:

•Primary motor and somatosensory cortex

–Lower limb, foot representation

•Anterior corpus callosum

Answer 7

Superficial branches of the ACA

Medial cortical branches

•Primary motor and somatosensory cortex

–Lower limb, foot representation

•Anterior corpus callosum

Question 8

____ artery:

Lateral cortical branches

•Superior branches

–Primary motor areas

–Face, hand, upper limb representation

MCA

–Broca’s area

–Prefrontal cortex

•Inferior branches

–Primary somatosensory cortex

–Parietal integrative areas

–Wernicke’s area

–Meyer’s loop of optic radiations

Answer 8

MCA

Lateral cortical branches

•Superior branches

–Primary motor areas

–Face, hand, upper limb representation

–Broca’s area

–Prefrontal cortex

•Inferior branches

–Primary somatosensory cortex

–Parietal integrative areas

–Wernicke’s area

–Meyer’s loop of optic radiations

**Deep branches to subcortical regions to be described below

Question 9

____ divides in the Sylvian fissure into superior and inferior divisions and stroke may be localized to one or both divisions. More superior branches radiate onto the lateral surface of frontal and anterior part of parietal cortex including ___ area.

Inferior branches supply posterior parietal, and primary and secondary auditory cortices including ____ area, Myers loop (superior quadrantanopia).

___ division infarcts may result in paralysis of face and upper limb as well as motor speech deficits (Broca’s aphasia)

____ division infarcts may result in Wernicke’s or more global aphasia, hemineglect, some somatosensory loss from face and upper limb, and visual field deficits

Answer 9

MCA divides in the Sylvian fissure into superior and inferior divisions and stroke may be localized to one or both divisions. More superior branches radiate onto the lateral surface of frontal and anterior part of parietal cortex including Broca’s area.

Inferior branches supply posterior parietal, and primary and secondary auditory cortices including Wernicke’s area, Myers loop (superior quadrantanopia).

Superior division infarcts may result in paralysis of face and upper limb as well as motor speech deficits (Broca’s aphasia)

Inferior division infarcts may result in Wernicke’s or more global aphasia, hemineglect, some somatosensory loss from face and upper limb, and visual field deficits

Question 10

___ artery:

Posterior cortical branches

–Occipital cortex

•Visual areas

–Inferior temporal lobe

–Orbital surface of frontal lobe

–Parietal association areas

–Posterior corpus callosum

Answer 10

PCA

•Posterior cortical branches

–Occipital cortex

•Visual areas

–Inferior temporal lobe

–Orbital surface of frontal lobe

–Parietal association areas

–Posterior corpus callosum

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Question 11

____ arteries are penetrating branches of the MCA that supply the internal capsule and structures of the basal ganglia.

Answer 11

Lenticulostriate arteries are penetrating branches of the MCA that supply the internal capsule and structures of the basal ganglia.

Question 12

___ arteries are often common in lacunar strokes.

Answer 12

Lenticulostriate arteries

Question 13

Deep Cerebral Arteries:

___ ___ from the MCA

___ ___ from the ACA

___ ___ ___ from the ICA

____ from the PCA

Answer 13

Deep Cerebral Arteries:

Lenticulostriate branches rom the MCA

Striate branches from the ACA

Anterior choroidal arteries from the ICA

Thalamoperforators from the PCA

Question 14

The terminal segment of ICA and initial segments ACA, MCA, and PCA give rise to deep cerebral branches that perforate the ___ ___ , ___ ____ and thalamus and related fiber tracts. These are common sites of small, lacunar infarcts and are distinct from more superficial strokes in the cortical fields of these vessels. Four named groups are:

1. MCA (lenticulostriate branches)
2. ACA(____)
3. ICA (____)
4. PCA (____)

Answer 14

The terminal segment of ICA and initial segments ACA, MCA, and PCA give rise to deep cerebral branches that perforate the basal ganglia, internal capsule, and thalamus and related fiber tracts. These are common sites of small, lacunar infarcts and are distinct from more superficial strokes in the cortical fields of these vessels. Four named groups are:

MCA (lenticulostriate branches)

ACA (striate branches)

ICA (Anterior choroidal branches)

PCA (Thalamoperforators)

Question 15

____ – ____ branches supply putamen and globus pallidus, and upper part of the internal capsule.

___ – branches of ___ ____ ___ supply mostly posterior limb of internal capsule

___ - ___ ___ ___ such as recurrent branch of Hubner supply parts of caudate, lower region of anterior limb of internal capsule

___ - ___ ____ ____ supply thalamus and posterior limb internal capsule

Answer 15

• MCA – lenticulostriate branches supply putamen and globus pallidus, and upper part of the internal capsule.
• ICA – branches of anterior choroidal artery supply mostly posterior limb of internal capsule
• ACA – medial striate arteries such as recurrent branch of Hubner supply parts of caudate, lower region of anterior limb of internal capsule
• PCA – thalamo perforating branches supply thalamus and posterior limb internal capsule

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Question 16

• ____ arteries are deep branches of the M1 segment of ____. Globus pallidus and putamen are mainly supplied by these vessels along with upper part of the anterior and posterior limbs and genu of internal capsule (overlaps ACA in anterior limb and anterior choroidal artery in posterior limb) . Lenticulostriate lacunar infarcts are most common.
• Other deep, striate branches (like the recurrent artery of Heubner) are branches of the A1 segment of ___. The head of the basal ganglia and anterior limb of internal capsule are supplied mainly by these vessels.

_____ arteries are branches of P1 (PCA). The thalamus as well as the posterior limb of internal capsule are mainly supplied by these vessels.

•Before giving off the posterior communicating branch and after the ophthalmic, the internal carotid artery gives rise to the __ ___ artery. This artery along with other choroidal arteries supplies choroidal plexus. In addition it also supplies the ___ limb of the internal capsule.

Answer 16

• Lenticulostriate arteries are deep branches of the M1 segment of MCA. Globus pallidus and putamen are mainly supplied by these vessels along with upper part of the anterior and posterior limbs and genu of internal capsule (overlaps ACA in anterior limb and anterior choroidal artery in posterior limb) . Lenticulostriate lacunar infarcts are most common.
• Other deep, striate branches (like the recurrent artery of Heubner) are branches of the A1 segment of ACA. The head of the basal ganglia and anterior limb of internal capsule are supplied mainly by these vessels.
• Thalamoperforating arteries are branches of P1. The thalamus as well as the posterior limb of internal capsule are mainly supplied by these vessels.
• Before giving off the posterior communicating branch and after the ophthalmic, the internal carotid artery gives rise to the anterior choroidal artery. The anterior choroidal artery along with other choroidal arteries supplies choroidal plexus. In addition it also supplies the posterior limb of the internal capsule.

Question 17

Answer 17

Question 18

Answer 18

Question 19

Answer 19

Question 20

A ‘classic’ teaching lesion is PICA infarct in the dorsolateral medulla (and, of course, posterior inferior cerebellum) – This is called ____ syndrome

Answer 20

Another ‘classic’ teaching lesion is PICA infarct in the dorsolateral medulla (and, of course, posterior inferior cerebellum) – Wallenberg’s syndrome

• Ataxia – cerebellar or inferior cerebellar peduncle damage
• Loss of pain and temperature on ipsilateral side of the face- spinal trigeminal tract and nucleus (there may be some contralateral loss given possible inclusion of cross trigeminothalamic fibers)
• To varying degrees loss of pain and temperature on contralateral side of the body – depending on extent of anterolateral spinothalamic tract involved
• Vertigo – vestibular nucleus
• Swallowing – CN X or nucleus ambiguus
• Hoarseness – CN X or nucleus ambiguus
• Changes in taste – nucleus solitarius and CN IX
• Autonomic signs – mostly due to medullary sympathetic centers, but also vagus and vagal nuclei

Question 21

___ ___ syndrome – infarcts of paramedian branches

oContralateral hemiparalysis and paralysis of contralateral face – corticospinal and corticobulbar fibers

oIpsilateral weakness of the face – damage to the internal genu of the facial nerve

oContralateral loss of vibration sense (touch) and conscious proprioception – medial lemniscus

oInability to abduct ipsilateral eye beyond the midpoint – abducens nerve and nucleus

Answer 21

·Medial pontine syndrome – infarcts of paramedian branches

oContralateral hemiparalysis and paralysis of contralateral face – corticospinal and corticobulbar fibers

oIpsilateral weakness of the face – damage to the internal genu of the facial nerve

oContralateral loss of vibration sense (touch) and conscious proprioception – medial lemniscus

oInability to abduct ipsilateral eye beyond the midpoint – abducens nerve and nucleus

Question 22

____ syndrome is a ‘classic’ teaching lesion for caudal, lateral pontine strokes

oIpsilateral ataxia – damage to cerebellum and middle cerebellar peduncle

oVertigo – damage to vestibular nuclei

oIpsilateral loss or decrease of pain and temperature sensation on the face – damage to spinal trigeminal tract

oContralateral loss or decrease of pain and temperature sensation on body and face – damage to anterolateral system

oIpsilateral hearing loss – this may result from damage to cochlear nuclei or involvment of the labyrinthine artery that branches from AICA and supplies the cochlea

Answer 22

·AICA syndrome is a ‘classic’ teaching lesion for caudal, lateral pontine strokes

oIpsilateral ataxia – damage to cerebellum and middle cerebellar peduncle

oVertigo – damage to vestibular nuclei

oIpsilateral loss or decrease of pain and temperature sensation on the face – damage to spinal trigeminal tract

oContralateral loss or decrease of pain and temperature sensation on body and face – damage to anterolateral system

oIpsilateral hearing loss – this may result from damage to cochlear nuclei or involvment of the labyrinthine artery that branches from AICA and supplies the cochlea

Question 23

·Lateral pontine syndromes can differ from this depending involvement of other short and long circumferential lesions. For instance __ ___ artery strokes involve the trigeminal motor and chief sensory nucleus whereas AICA syndrome does not.

Answer 23

·Lateral pontine syndromes can differ from this depending involvement of other short and long circumferential lesions. For instance superior cerebellar artery strokes involve the trigeminal motor and chief sensory nucleus whereas AICA syndrome does not.

Question 24

___ ___ syndrome – infarcts of paramedian branches

oContralateral hemiparalysis and paralysis of contralateral face – corticospinal and corticobulbar fibers

oIpsilateral weakness of the face – damage to the internal genu of the facial nerve

oContralateral loss of vibration sense (touch) and conscious proprioception – medial lemniscus

oInability to abduct ipsilateral eye beyond the midpoint – abducens nerve and nucleus

Answer 24

·Medial pontine syndrome – infarcts of paramedian branches

oContralateral hemiparalysis and paralysis of contralateral face – corticospinal and corticobulbar fibers

oIpsilateral weakness of the face – damage to the internal genu of the facial nerve

oContralateral loss of vibration sense (touch) and conscious proprioception – medial lemniscus

oInability to abduct ipsilateral eye beyond the midpoint – abducens nerve and nucleus

Question 25

Arterial Supply of Midbrain: \_\_\_\_ branches supplies: –CN III –Parts of cerebral peduncle and SN –Red nucleus –Superior cerebellar peduncle \_\_\_\_\_l branches of basilar or ____ \_\_\_\_ artery supplies: * Medial lemniscus * Anterolateral system * Parts of cerebral peduncle and SN \_\_ ___ artery supplies the: –Tectum

Answer 25

Arterial Supply of Midbrain: •Paramedian branches –CN III –Parts of cerebral peduncle and SN –Red nucleus –Superior cerebellar peduncle * Circumferential branches of basilar or PCA * Medial lemniscus * Anterolateral system * Parts of cerebral peduncle and SN * e.g., superior cerebellar artery –Tectum -\>

Question 26

\_\_\_\_ syndromes: basal lesions involving paramedian branches to the midbrain arise from the P1 segment of the posterior cerebral artery. Infarcts involve the cerebral peduncle and CN III along with parts of the substantia nigra and red nucleus. Neurological deficits include a) contralateral hemiparalysis b) oculomotor palsy (the eye is in down and out position) and mydriatic (dilated) pupil. * Other basal midbrain lesions may include loss or decreased somatosensation (medial lemniscus and anterolateral system) and tremor or other involuntary movements (\_\_\_ ___ is the region important for movement). * As mentioned above, berry aneurysm is common at distal branch points of the basilar artery. Infarct or ischemia may result at base of the midbrain and/or damage to the oculomotor nerve. Berry aneurysm: A small aneurysm that looks like a berry and classically occurs at the point at which a cerebral artery departs from the circular artery (the circle of Willis) at the base of the brain.

Answer 26

basal midbrain syndromes: basal lesions involving paramedian branches to the midbrain arise from the P1 segment of the posterior cerebral artery. Infarcts involve the cerebral peduncle and CN III along with parts of the substantia nigra and red nucleus. Neurological deficits include a) contralateral hemiparalysis b) oculomotor palsy (the eye is in down and out position) and mydriatic (dilated) pupil. * Other basal midbrain lesions may include loss or decreased somatosensation (medial lemniscus and anterolateral system) and tremor or other involuntary movements (\_\_\_ ___ is the region important for movement). * As mentioned above, berry aneurysm is common at distal branch points of the basilar artery. Infarct or ischemia may result at base of the midbrain and/or damage to the oculomotor nerve. Berry aneurysm: A small aneurysm that looks like a berry and classically occurs at the point at which a cerebral artery departs from the circular artery (the circle of Willis) at the base of the brain.

Question 27

What kind of syndrome?

Answer 27

Weber's Syndrome Paramedian branches are occluded. * Weber’s syndrome (another classic teaching lesion): basal lesions involving paramedian branches to the midbrain arise from the P1 segment of the posterior cerebral artery. Infarcts involve the cerebral peduncle and CN III along with parts of the substantia nigra and red nucleus. Neurological deficits include a) contralateral hemiparalysis and b) oculomotor palsy (the eye is in down and out position) and mydriatic (dilated) pupil. * Other basal midbrain lesions may include loss or decreased somatosensation (medial lemniscus and anterolateral system) and tremor or other involuntary movements (substantia nigra).

Question 28

The anterior choroidal artery is a branch of the internal carotid. It contributes blood supply to the lateral ___ body, __ \_\_, and posterior limb of the ___ \_\_\_.

Answer 28

The anterior choroidal artery is a branch of the internal carotid. It contributes blood supply to the lateral geniculate body, globus pallidus, and posterior limb of the internal capsule.

Question 29

A patient who suffered a stroke presents with a paralysis of the right side of the lower face, right spastic paralysis of the limbs, deviation of the tongue to the right with no atrophy, and no loss of taste from any region of the tongue. Which of the following structures was most likely affected by the stroke?

Answer 29

Internal capsule of the left side

Question 30

The ___ areas plays an important role in the programming or sequencing of responses that compose complex, learned movements. They receive significant inputs for this process from the posterior parietal lobule, and in turn, signal appropriate neurons in the brain stem and spinal cord (both flexors and extensors).

Question 31

A 74 year old female was brought to the hospital after she suffered a stroke. Several days later, she was unable to perform certain types of learned, complex movements (referred to as apraxia). Which of the following regions of the cerebral cortex was most likely affected by the stroke?

Answer 31

Pre-motor cortex.