Medical Imaging
What is an MRI?
Magnetic resonance imaging (MRI) is a medical imaging technique used to produce high quality images of the inside of the human body. A scanner emits a strong magnetic field inside the brain (or elsewhere in the body) and produce signals that are analyzed by a computer to produce detailed images.
Purpose of an MRI
Different organs can be studied with MRI imaging. MRI neurography is a technique that specifically images the peripheral nerves. This technique can be a complement to electrodiagnostic testing. MRI neurography can detect abnormalities earlier than electrodiagnostic testing after nerve injury and can also help your doctor differentiate between different types of peripheral neuropathy.
Other MRI techniques can be performed to exclude other disorders that produce similar symptoms.
How is an MRI Done?
Typically, the patient is placed into a tube-like cylinder (scanner) while lying on a mobile table. The patient is asked to lie very still. Usually, the fit is quite tight and sometimes claustrophobia (fear of enclosed/small places) can be a problem.
Due to the use of a magnetic field, there are patients that cannot undergo MRI. Patients with a pacemaker (or any metal implant) are not able to undergo an MRI. Some modern orthopedic implants are inert and do not react with the magnetic field of the MRI.
Does an MRI Hurt?
For most people, the procedure is painless. However, sometimes claustrophobia can be a problem, and the patient is given a medication for relaxation.
What is a CT Scan?
A CT scan is an x-ray procedure that combines many x-ray images with the aid of a computer to generate cross-sectional views and, if needed, three-dimensional images of the internal organs and structures of the body. A CT scan is used to define normal and abnormal structures in the body and/or assist in procedures by helping to accurately guide the placement of instruments or treatments.
Purpose of a CT Scan
A CT scan is not a test for peripheral neuropathy, but is performed to exclude other disorders that produce similar symptoms. CT scans are performed to analyze the internal structures of various parts of the body.
How is a CT Scan Done?
Prior to a CT scan, patients are often asked to avoid food, especially when contrast material is to be used. Contrast material may be injected intravenously, or administered by mouth or by an enema in order to increase the distinction between the signal of various organs or areas of the body.
Patients are placed on a movable table, and the table is slipped into the center of a large donut-shaped machine, which takes the x-ray images around the body. The procedure usually takes around half an hour.
Do CT Scans Hurt?
A CT scan is painless, but requires some patience, as the patient must remain still. Patients who are claustrophobic (fear of enclosed/small places) may need a medication for relaxation.