Brainstem

Question 1

Caudal medulla landmarks

Answer 1

Fused baby feet
Central canal
Pyramids - corticospinal tract
Internal arcuate fibers forming the medial lemniscus (decussation of the dorsal column pathway)
Nucleus gracilis
Nucleus cuneatus
Spinal tract (descends from the face, through the semilunar ganglion, into the pons and then down to the spinal cord to synaps with spinal nuc.. of V) and nucleus of V

Less noticeable:
Nuc. solitary tract
Lat. cuneate nuc

Question 2

Rostral (open) medulla landmarks

Answer 2

4th ventricle (wide open)
Inferior cerebellar peduncle (very posterior and lateral)
Inferior olivary nucleus
Medial longitudinal fasciculus (eye reflexes)

Less noticeable:
nuc. solitarius, motor nuc. of XII, cochlear nuclei (also post. and lateral)

Question 3

Caudal pons landmarks

Answer 3

Deep cerebellar nuclei (fastigial, globose, emboliform, dentate)
Basal pons
Ponto-cerebellar (mossy) fibers
Huge middle cerebellar peduncle (between pons and cerebellum)

Less noticeable

6th and 7th nuclei

Question 4

Rostral pons landmarks

Answer 4

“Flipped” medial lemniscus ready to enter thalamus feet first
Huge basal pons
Spinothalamic tract enters VPL also
Bit of PAG

Question 5

Caudal midbrain landmarks

Answer 5

Decussation of the superior cerebellar peduncle (efferent, will synapse on red nucleus)
Clear cerebral aqueduct
Inferior colliculus (auditory, vdSLIM, medial geniculate nuc.)
Cerebral peduncles (corticospinal tract runs down center)
Level of CN IV

Question 6

Rostral midbrain landmarks

Answer 6

Substantia nigra - dopamine, loss of is associated with Parkinson’s disease
Red nucleus - communicates with thalamus (and cerebellum) re: movement
CN III
Well defined cerebral peduncles