Diagnosis

Your doctor will run tests to pinpoint where your peripheral nerve tumor is situated and what type of tumor it is.

Tests

You might undergo one or more of the following tests.

• MRI. This is the preferred method for imaging peripheral nerve tumors. This scan uses a magnet and radio waves to produce a detailed 3D view of your nerves and surrounding tissue. It can help determine whether you have a tumor and whether the tumor is inside or outside the nerve.
• CT scan. A CT scanner rotates around your body to record a series of images. Although this test is not as useful as an MRI in diagnosing a peripheral nerve tumor, your doctor might recommend it if you can't have an MRI.
• Electromyogram (EMG). For this test, your doctor places small needles in your muscles so an electromyography instrument can record the electrical activity in your muscle as you try to move it.
• Nerve conduction study. You're likely to have this test along with your EMG. It measures how quickly your nerves carry electrical signals to your muscles.
• Tumor biopsy. If imaging tests identify a nerve tumor, your doctor might remove and analyze a small sample of cells (biopsy) from your tumor. Depending on the tumor's size and location, you might need local or general anesthesia during the biopsy.
• Nerve biopsy. If you have a condition such as a progressive peripheral neuropathy or enlarged nerves that mimic nerve tumors, your doctor may take a nerve biopsy.