A 53-year-old Caucasian male comes in with a 2-week history…
A 53-year-old Caucasian male comes in with a 2-week history of severe headaches mostly during the night. The patient is pacing while he is talking. During the history taking, he states that the symptoms of pain around one eye last for 30 to 90 minutes in duration. He also states that there is ipsilateral lacrimation, conjunctival injection, and nasal congestion during the attacks. The patient states that he has had these headaches two or more times in a day over a period of several weeks. He cannot point to one thing that triggers them. On examination, the patient has features of partial Horner’s syndrome. His vital signs are temp. 97.0 F, HR 80/min, RR 16/min, BP 126/80 mmHg. The patient’s headache is most likely: