B7.028/029 Prework: Brainstem Lesions

Question 1

why are CNs different than spinal nerves

Answer 1

1. exit at regular intervals
2. components of each nerve vary more than spinal nerves
3. brainstem structure and function varies by level more than the spinal cord

Question 2

common brainstem lesion etiology

Answer 2

stroke

Question 3

anterior spinal artery

Answer 3

midline artery of medulla

Question 4

vertebral arteries

Answer 4

lateral arteries of medulla

Question 5

posterior inferior cerebellar artery (PICA)

Answer 5

wraps around middle of the medulla

Question 6

anterior inferior cerebellar artery (AICA)

Answer 6

wraps around bottom of pons

Question 7

what are motor nuclei in the brainstem

Answer 7

• motor neurons that live in the brainstem; axons exit in cranial nerves and innervate head and neck muscle
• analogous to ventral horn
• includes parasympathetic preganglionics

Question 8

what are sensory nuclei in the brainstem

Answer 8

• receive sensory information from primary receptor neurons
• analogous to dorsal column nuclei, substantia gelatinosa for body sensation
• may receive autonomic afferent information