I'm pretty certain that she is referring to the mastoid bone, which is a part of the skull, just behind the ear, about where AN surgery is done.
Mastoiditis is often a consequence of a middle ear infection that spreads to the mastoid bone. One obvious symptom is when the skin behind the ear turns red and in some cases, the ear will 'drain'. Headaches are also common with this condition. A skull X-ray or CT scan is used to confirm a diagnosis of mastoiditis. The usual treatment is with antibiotics, which is generally successful. However, surgical drainage of the middle ear may sometimes be necessary. If untreated, mastoiditis can spread infection throughout the body and can have very dire consequences. It cannot be ignored.
Although she seems to be experiencing AN-like symptoms, a re-growth this quickly after surgery (6 months) is probably not the cause of this lady's problems. However, a case of mastoiditis might be the culprit. I almost hope so, for her sake.
Jim
