Anatomy and Physiology XI

Question 1

What four arteries compose the posterior circulation of the brain?

Answer 1

ASA, PICA, AICA, PCA (p.422)

Question 2

What three functional areas does the ASA supply?

Answer 2

Lateral corticospinal tract, medial lemniscus, caudal medulla (CN XII) (p.422)

Question 3

What symptoms are associated with an infarction of the ASA?

Answer 3

Contralateral hemiparesis of the lower limbs; decreased proprioception; ipsilateral hypoglossal dysfunction (tongue deviates ipsilaterally) (p.422)

Question 4

What type of stroke is typically seen in infarction to the ASA?

Answer 4

Bilateral stroke (p.422)

Question 5

What causes medial medullary syndrome?

Answer 5

Infarct of the paramedian branches of the ASA and vertebral arteries (p.422)

Question 6

What functional area is supplied by PICA?

Answer 6

The lateral medulla (p.422)

Question 7

What important structures of the lateral medulla are supplied by PICA?

Answer 7

Vestibular nuclei, lateral spinothalamic tract, spinal trigeminal nucleus, nucleus ambiguus, sympathetic fibers, inferior cerebellar peduncle (p.422)

Question 8

What symptoms are associated with an infarction of PICA?

Answer 8

Vomiting, vertigo, nystagmus; decreased pain and temperature sensation to limbs and face; DYSPHAGIA,HOARSENESS, decreased gag reflex; ipsilateral Horner’s syndrome; ataxia, dysmetria (p.422)

Question 9

What is Lateral Medullary (Wallenberg’s) Syndrome?

Answer 9

A PICA lesion causing nucleus ambiguus effects (p.422)

Question 10

What artery is infarcted in Wallenberg’s syndrome?

Answer 10

PICA (p.422)

Question 11

What three important structures are supplied by AICA?

Answer 11

Lateral pons; Middle and Inferior cerebellar peduncles (p.422)

Question 12

What important structures of the lateral pons are supplied by AICA?

Answer 12

Cranial nerve nuclei, vestibular nuclei, facial nucleus, spinal trigeminal nucleus, cochlear nuclei, sympathetic fibers (p.422)

Question 13

What symptoms are associated with an infarction of AICA?

Answer 13

Vomiting, vertigo, nystagmus, PARALYSIS of face, decreased lacrimation, salivation, decreased taste from anterior 2/3 of tongue, decreased corneal reflex. Decreased pain and temperature sensation of the face; ipsilateral decrease in hearing; ipsilateral Horner’s syndrome, ataxia, dysmetria (p.422)

Question 14

What syndrome is caused by an infarct in AICA?

Answer 14

Lateral pontine syndrome (p.422)

Question 15

Lesions of what artery cause facial nucleus effects?

Answer 15

AICA (p.422)

Question 16

What is a common clinical finding in AICA infarct?

Answer 16

Facial droop (p.422)

Question 17

What two important areas are affected by PICA infarct?

Answer 17

Occipital cortex; visual cortex (p.422)

Question 18

What symptoms are associated with an infarction of the PCA?

Answer 18

Contralateral hemianopia with macular sparing (p.422)

Question 19

Name the two communicating arteries.

Answer 19

Anterior and posterior communicating arteries (p.422)

Question 20

Which two sites are commonly associated with saccular (berry) aneurysms?

Answer 20

The Anterior and Posterior communicating arteries (p.422)

Question 21

Lesion to the anterior communicating artery has what effect?

Answer 21

Impingement on cranial nerves (p.422)

Question 22

What deficits are associated with lesion to the anterior communicating arteries?

Answer 22

Visual field defects (p.422)

Question 23

What deficits are associated with lesion to the posterior communicating arteries?

Answer 23

CN III palsy (eye is down and out) with ptosis and pupil dilation (p.422)

Question 24

What type of lesion commonly affects the anterior communicating arteries?

Answer 24

Aneurysms; typically not strokes (p.422)

Question 25

What type of lesion commonly affects the posterior communicating arteries?

Answer 25

Aneurysms; typically not strokes (p.422)