A 45-year old woman presented with a twelve-month history of intense migraines. She described episodes of blurred vision in association with the headaches, during which she invariably found that one or other of her pupils became dilated with a degree of eyelid retraction on the affected side. These unusual symptoms resolved spontaneously with improvement of the headache.
After exclusion of a lesional cause with brain and neck imaging, we concluded that her symptoms were secondary to autonomic dysfunction in relation to her headache.
Horner's syndrome is due to paralysis of the ipsilateral cervical sympathetic chain and comprises ptosis, miosis, enopthalmos and anhidrosis. A Reverse Horner's syndrome, otherwise known as Pourfour du Petit, in theory, is the opposite, and comprises eyelid retraction, mydriasis and hyperhidrosis. Where documented, it is attributed to irritation, rather than complete deficiency of the ipsilateral sympathetic chain. Previous case reports have shown that Pourfour du Petit can occur due to the same mechanisms as a Horner's syndrome. In only one other case report has it been described as an autonomic feature in relation to headache.