The Mastoid AP View X-Ray is a medical imaging test that allows doctors to visualize the mastoid bone, which is located behind the ear. This test is typically ordered to evaluate for inflammation, infection, or other abnormalities affecting the mastoid bone.Why get tested?A Mastoid AP View X-Ray may be ordered by a healthcare provider to evaluate for mastoiditis (inflammation of the mastoid bone), middle ear infections, or other conditions that may affect the mastoid bone. The test can help the doctor visualize the bone and identify any signs of inflammation, fluid accumulation, or other abnormalities.