Diagnostic Tests for Metastatic Tumors of the Brain and Spine

Diagnosing a metastic tumor to the brain or spinal cord involves several steps. Your doctor typically starts by asking about your medical history, including any previous illnesses that might have weakened your immune system or involved radiation therapy. Your doctor will also ask about your family history, your habits, and your lifestyle.

Doctors use a neurological exam to diagnose the tumor. During this exam, your doctor looks for changes to your vision, hearing, balance, coordination, strength, and reflexes. These changes can identify which part of your brain may be affected by a tumor.

Imaging tests that take pictures of your brain also help diagnose a tumor. Doctors use a variety of imaging technologies, each offering different insights to confirm the presence, location, and type of tumor that may be present.

MRI to diagnose glioblastoma
Magnetic resonance imaging (MRI) is the most common imaging doctors use to diagnose glioblastomas. This test uses radio waves and magnets to create images of brain structures. A technologist or nurse may perform this scan by injecting contrast dye into your arm to illuminate the tumor’s location. Doctors use 2 main types of MRI to diagnose glioblastoma:

• Functional MRI: Maps brain activity by evaluating the structures of the brain and detecting changes in blood flow
• Perfusion MRI: Identifies parts of the brain with less blood flow, a potential sign of a tumor blocking the path
• Tractography: Visualizes white matter tracts which carry electric signals and sensory information for the central nervous system. These images are uploaded to neurosurgical navigation system in the operating room to guide the surgeon around critical pathways as the tumor is removed.

CT scan to diagnose brain tumors
Some people cannot have an MRI because the magnets interfere with implanted medical devices such as pacemakers and cochlear implants. Computed tomography (CT) scans take combine multiple X-rays and provide doctors with another way to see structures in the brain.

Your doctor may order a spinal tap to rule out the presence of infection like meningitis. Infections may produce symptoms similar to tumors of the brain and spine.