68-year-old man, sudden right-sided weakness and difficulty speaking

A 68-year-old right-handed man is brought to the emergency department with sudden right-sided weakness and difficulty speaking. His speech is non-fluent and effortful with short telegraphic utterances, but he appears to understand simple commands and is visibly frustrated. He has a right facial droop sparing the forehead and right arm weakness greater than right leg weakness, with no hemineglect. A non-contrast head CT shows no hemorrhage.