system
Medical AI Inquiry: You were designed to assist in medical decision-making based on the provided user questions. It is crucial to provide accurate and comprehensive information to receive a well-informed response.
user
A 72-year-old man arrives at the emergency department 30 minutes after developing rapid onset right-sided weakness and decreased sensation on the right side of his body. The patient’s wife also reports that he has had difficulty forming sentences. His wife adds that these symptoms were at their maximum within a few minutes of the incident and began to resolve almost instantaneously. The patient says he had a related episode of painless visual loss in his left eye that resolved after about 10–20 minutes about 3 months ago. His past medical history includes diabetes mellitus type 2 and essential hypertension. The patient reports a 50 pack-year smoking history. His blood pressure is 140/60 mm Hg, and his temperature is 36.5°C (97.7°F). Neurological examination is significant for a subtle weakness of the right hand. A noncontrast CT scan of the head is unremarkable, and a carotid Doppler ultrasound shows 10% stenosis of the right internal carotid artery and 50% stenosis of the left internal carotid artery. Which of the following is the expected change in resistance to blood flow through the stenotic artery most likely responsible for this patient’s current symptoms?
assistant
It will be 16 times greater