If you have the symptoms of
giant cell arteritis (GCA) and your doctor believes
you may have it, he or she may order a temporal artery biopsy to make
sure.
Giant cell arteritis can occur at various points along an
artery 
. To test for giant cell arteritis, your doctor
may have a surgeon take a sample of a blood vessel on your temple and test it
for
inflammation.
If a temporal artery biopsy shows no signs of inflammation but your
symptoms strongly suggest giant cell arteritis, your doctor may:
- Order another biopsy on the other side of your
head.
- Proceed with treatment without further biopsy
testing.
If you are taking high-dose corticosteroids, the biopsy result may
not be accurate. In this case, any biopsy testing must be performed as soon as
possible, preferably within 2 to 5 days. Biopsies done more than 7 days after
the start of high-dose corticosteroids may be falsely normal (false-negative).
