The Stalk-Like: Brainstem Neuroanatomy!
Andreas Vesalius (1514-1564)
Anatomist born in Brussels
Vesalius' and Valverde's drawings of the posterior view of the human brainstem and deep gray matter of the brain.
2) Rule of 4x4
1st) 4 CNs above pons, 4 CNs in pons, and 4 CNs below pons
2nd) 4 midline CNs: 3, 4, 6, 12
3rd) 4 Mid structures: Motor pathway (CST), Medial lemniscus, MLF, Medial CNs
4th) Side structures: Spinothalamic, Spinocerebellar, Sensory portion CN V, Sympathetic fibers
3) The brainstem is mainly divided into
Midbrain Upper – sup collicular level
Midbrain Lower – inf collicular level
Pons
Medulla Upper – inf olivary nucleus level;
Medulla Lower – pyramidal decussation level
4) Midbrain Upper
First, draw the heads, arms, and then the legs of the gingerbread man.
After drawing the CST, substantia nigra, red nucleus, aqueduct, CN 3, medial lemniscus, and lastly, the spinothalamic tract.
5) Midbrain Lower
First, draw the head and the legs.
After drawing the CST, substantia nigra, decussation of sup cerebellar peduncle, aqueduct, CN4, medial lemniscus, and lastly, the spinothalamic tract.
6) Generally, CNs exit relatively ant to ventricular system and don't cross to opposite side. The exception is dumb CN 4, which crosses and passes over the brainstem roof. No wonder the lord delegated the most insignificant of all the CNs functions to this untrustworthy nerve.
7) Pons
First, draw a buttock, and place the 4th ventricle.
After, draw the CST, 6 CN, 7 CN, 5 CN, 8 CN.
Also, draw the PPRF. Also, draw ML medially, and spinothalamic, and spinocerebellar tracts.
8) CN7 is naughty and heard there was some sex over the 4th ventricle, on arriving there it realized that it was misunderstood. It was six, not sex, and he traveled around the nucleus of CN 6 to exit anterolaterally.
9) Medulla Upper
Draw three bumps anterior and posterior.
Draw CN 12, 7, 10, 8, and 5.
After, place the ML, solitarius, and ambiguous.
Also, spinothalamic and spinocerebellar.
Lastly, inferior olivary nucleus
10) Medullar Lower
Resembles spinal cord.
Draw pyramidal decussation.
Draw nucleus gracilis and cuneatus, and CN 5.
After draw ML decussation.
11) Summary
12) Tectum, tegmentum, basis
Think that the brainstem is a house!
13) Histology sections
Midbrain Upper – sup collicular level
Midbrain Lower – inf collicular level
Pons
Medulla Upper – inf olivary nucleus level;
Medulla Lower – pyramidal decussation level
14) Midbrain Upper
15) Midbrain Lower
16) Pons
17) Medulla Upper
18) Medulla Lower
19) Brainstem landmarks
“CRUS, PONTS, DICTA”
20) Brainstem vascularization
Midbrain: PCA & SCA
Pons: Basilar and AICA
Medulla: ASA & PICA
21) Cranial Nerves exit
22) Frontal view of brainstem
23) Posterior view of brainstem
24) Figure legend
