Does mastoiditis cause chronic headaches?

Difficult question . True mastoiditis - a purulent infection of the mastoid bone - is ridiculously rare in this day. In my 22 years of practice I have never seen it. I have, however, had patients referred to me with pain around their ears who were told they had mastoiditis who had something else such as jaw spasm. Sometimes patients have a ct or MRI with benign swelling misdiagnosed as mastoiditis. See an ENT doctor.
No. Mastoiditis causes pain behind or around the ear and is usually associated with redness and swelling behind the ear as well as a history of ear disease. Acute or even chronic mastoiditis rarely is the cause of a generalized headache.