Cardiothoracic Surgery Patient Care – Esophageal Cancer

Chest MRI – A non-invasive procedure that uses powerful magnets and radio waves to construct pictures of the body.

Unlike conventional radiography and Computed Tomographic (CT) imaging which make use of ionizing, and hence, potentially harmful, radiation (X-rays) passing through a patient to generate images, MRI imaging is based on the magnetic properties of atoms.

A powerful magnet generates a magnetic field roughly 10,000 times stronger than the Earth’s. A very small percentage of hydrogen atoms within the body will align with this field. The “nuclear” in the original, and now seldom used, name refers to the proton in the nucleus of the hydrogen atom and does not imply radioactivity.

When focused, short radio wave pulses are broadcast towards the aligned hydrogen atoms in tissues of interest, they will return a signal of their own. The subtle differing characteristics of that signal from dissimilar tissues combined with complex mathematical formulas solved on modern computers is what enables MRI to differentiate between various organs, and potentially, provide contrast between benign and malignant tissue.

Any imaging plane, or “slice”, can be projected, and then stored in a computer or printed on film. MRI can easily be performed through clothing and bones, however, certain types of metal in or around the area of interest can cause significant errors in
the reconstructed images (artifact).

During magnetic resonance imaging (MRI) scan, a narrow table
moves the patient through a tunnel-like structure which creates a magnetic field
through which radio waves are sent, creating a 3-D image of the internal structures.

MRI stands for magnetic resonance
imaging. It is a relatively new
technology that allows imaging
of the interior of the body without
using X-rays or other types of
ionizing radiation. An MRI scan
is capable of showing fine detail
of different tissues. Its use is
rapidly increasing while the
use of standard X-rays is
decreasing.