Brainstem 3 Flashcards
Medial rectus innervation
CN 3
Lateral rectus innervation
CN 6
What the roof of the mid brain called?
Tectum
Name the commisure anterior to the pre tectal area where left and right MLBs join
Posterior commisure
What are the 2 bumps on the tectum called?
Superior colliculli (little hill in Latin)
Visual reflexes (not pathway) occur here
Which nerve constricts pupils?
CN 3
Describe the pupillary construction reflex
Retina ➡️ pretectal area ➡️ CN3 ➡️ ciliary ganglion ➡️ constrictor pupillae
Describe the pupillary dilation reflex
Retina ➡️ dorsolateral brainstem ➡️ T1 cord ➡️ sympathetic chain ➡️ sup cervical ganglion ➡️ dilator pupillae
What is the consensual reflex?
Cover 1 eye- that pupil dilates
Pupil of uncovered we also dilates a pre tectal area connects the R & L eyes.
Shine light in uncovered eye- constricts- take hand away quickly and that pupil would have constricted!!
Describe the steps of the light reflex, from when light shines in the eye to shutting eyes and turning head away
Retina ➡️ sup colliculus ➡️ tectobulbar/spinal tracts ➡️ cervical cord ➡️ LMNs to NRC muscles ➡️ CN7 ➡️ orbicularis oculi
What are the 2 MAIN arteries that supply the brain stem?
Vertebral & basilar
‘Vertebro-basilar system’
Name the 3 groups of arteries that come of the v-b system to supply the brainstem
Paramedian branches
Short circumferentials
Long circumferentials
Which of the 3 groups of arteries that branch off the v-b system also supplies the cerebellum?
Long circumferentials
What artery is blocked in dorsolateral medullary syndrome (of Wallenberg)
PICA
What is Ageusia?
Loss if taste
