This question is tricky. I used to always miss this presentation. This is laterally medullary syndrome- which most of us have memorizes is a PICA infarct. Fun fact, PICA comes off the vertebral artery.

This is how I remember the sx. If this helps at least one person I will be glad I am exposing my twisted brain.

3+5=8 & 9-11 & B-P.

3: Horner's syndrome 5:spinal trigeminal- ipsi face pain and temp loss 8: vestibular signs, vertigo diplopia

9-11: Nucleus ambiguous, diminshed gag, dysphagia B: Cerebellar - inferior cerebellar peduncle, ipsi ataxia P: Contra pain and temp, cuz this shit was so painful to memorize I throw it to the other side.

• Crossed signs of decreased pinprick sensation over opposite sides of face and body = Pathology in the brainstem IPSILATERAL to side where face pinprick sensation is lost
• Other aspects of patient’s presentation are consistent with Wallenberg syndrome (stroke of lateral medulla), including vertigo, ataxia and weakness of the palate
• Key idea: If patient with suspected brainstem stroke has symptoms that localize to nucleus ambiguus (motor vagal nucleus that when damaged can present as dysphagia, hoarseness, and dysarthria) then you are almost certainly dealing with a lateral medullary syndrome
• Although lateral medullary syndrome most often associated with stroke/hemorrhage involving the Posterior Inferior Cerebellar artery (PICA), important to remember that the PICA comes off the vertebral artery (reason why vertebral dissections can present with lateral medullary syndrome)

Clinical picture sounds a lot like Wallenberg syndrome, which is classically due to posterior inferior cerebellar artery involvement leading to lateral medullary ischemia.

HOWEVER, vertebral artery dissection is another cause of Wallenberg syndrome and was also covered in one of the UWORLD questions with a similar presentation.

From. the man, the myth, the legend - Dr. Ryan https://d1yboe6750e2cu.cloudfront.net/i/e9f7093da7ea75eafd19ab63669f9fc07d868e14 https://d1yboe6750e2cu.cloudfront.net/i/1e7ee9f42ffdeddfc37e0384006bf153c1a5788c