A 77 year old woman of Scandinavian descent presents with subacute fever, fatigue, and weight loss. She has been undergoing a workup for fever of unknown origin. She is finally referred to a neurologist because of a new headache. The characteristics of the headache, though, are nonspecific. She also has some jaw claudication with a rapid onset of pain once she starts chewing. Still, no diagnosis is made until she presents to the emergency room with transient monocular visual loss. There was a temporary partial field cut that returned when she was in the ER. The ophthalmologic exam was unremarkable.
Challenge: You better make the diagnosis before she has permanent visual loss; what is this?
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