Unfortunately, results from this technique are nonspecific. Biopsy of the brain is the most direct means of making the diagnosis of CNS vasculitis. Obviously, such a procedure should never be taken lightly, but it may be vitally important to secure the diagnosis, since the treatment for this condition is long-term and may have significant risks. This biopsy is done under general anesthesia in the operating room where a small piece of brain is taken and studied under the microscope and evaluated for possible infection. The procedure can generally be done with minimal adverse effects and the information provided can at times be life-saving.
Many conditions can mimic vasculitis.
These mimics have completely different treatments e.g. antibiotics for infections or surgery or radiation therapy or chemotherapy for brain tumors. Thus it is essential to rule out such diagnoses before embarking upon therapy for CNS vasculitis. Not surprisingly, patients are often reluctant to have a brain biopsy unless the reasons are adequately explained. The diagnosis and care of patients with CNS vasculitis is a team effort. This team needs to include a physician such as a rheumatologist or immunologist who is expert in vasculitic diseases of the nervous system.