welcome redditors!to snoo-finity ... and beyond!

NBME 21 Answers

nbme21/Block 2/Question#41

A 75-year-old woman has the sudden onset of Horner ...

Posterior inferior cerebellar

Login to comment/vote.

This is lateral medullary/PICA/Wallenberg syndrome. The woman has damage in the sympathetic chain (sensory syndromes are lateral according to the rule of 4s) resulting in Horner syndrome, spinothalamic tract (pain/temp which are also sensory), and CN IX and CN X dysfunction resulting in the dysphagia/dysarthria (helps us localize to the medulla).

nala_ula  Also, just to add, FA specifies that Nucleus ambiguus effects (dysphagia, hoarseness, decreased gag reflex) are specific to PICA lesions. +1  
cienfuegos  Thanks for the input. I have always found this topic to be tricky and just came across this article that helped me out a ton regarding the rule of 4's hoscyamine mentions above. https://rdcu.be/bLjOB +1