CT Scan – Also known as a CAT scan, computed tomography uses xrays and computers to take images of your body. CT scans are most often used to take pictures of bone, blood vessels, check for cancer, blood clots, and to see if there is internal bleeding. Sometimes dyes are injected into the blood stream so that it is easier to see a contrast between different types of tissues. CT scans are very useful, but they do use radiation, so that is a precaution for CT scans.
EMG – Electromyography is used to measure the electrical activity of the muscle. Muscles and nerves have an electrical signal that can be measured when they are contracting. By recording these signals, trained personnell can determine if there is something going on at the muscle, the nerve, or the junction of the muscle and the nerve. EMG is often done together with a nerve conduction velocity test (NCS- see below) to gain more complete information.
MRI – Magnetic resonance imaging is a safe and noninvasive way to take pictures of the inside of the body. Strong magnetic pulses cause the hydrogen atoms in the body to line up in the same direction (like a needle on a compass). The signal that they give as they return to their regular position gives the technician a picture of the soft tissues of the body. There is no ionizing radiation with an MRI like there is with an xray or a CT scan, so MRI is often a preferred test.
NCS, or nerve conduction study – This is a test that’s done to see how well the nerve is conducting a signal. If the impulses are not transmitting as quickly as they should, it indicates that there is something abnormal about the nerve. There are a number of different problems that this could indicate. The test is done using electrodes on the skin and using mild electric shock. This test is also known as a nerve velocity test, or NCV.
Xray – Xrays are one of the most common types of imaging that is used. Electromagnetic radiation is used to capture pictures of the body. Bones absorb the most radiation, so they appear white on the xray. Soft tissues absorb less, so they appear gray on an xray. Xrays are most typically used to diagnose problems with the skeleton, because soft tissue is not well seen on an xray. Xrays are fairly cheap and easily obtained, but amount of radiation is a precaution.