A 75-year-old woman presented with horizontal binocular diplopia, right-sided ptosis, and a new headache that was progressive over 3 days. She reported difficulty opening her jaw, pain when chewing, and a 2.3-kg weight loss. The week prior, she experienced left-sided ptosis that persisted for 2 days and subsequently resolved. She denied vision changes, eye pain, scalp tenderness, and myalgias. Past medical history included schizophrenia, hypothyroidism, and supraventricular tachycardia.