Preventative Health

Magnetic Resonance Imaging (MRI)

MRI is a non-invasive imaging technology that produces three dimensional detailed anatomical images without the use of X-rays. It is often used for disease detection, diagnosis, and treatment monitoring. It is based on technology that excites and detects the change in the direction of the rotational axis of protons found in the water and fat that make up living tissues.


MRI scanners are particularly well suited to image the soft tissues of the body. They differ from computerized tomography (CT), in that they do not use any x-radiation. The brain, spinal cord, nerves, muscles, ligaments, tendons and joint spaces are seen more clearly with MRI than with CT; for this reason MRI is the diagnostic modality of choice to image soft tissue and joint spaces. MRI is also exceptional when evaluating bones; the non-calcific tissue of bone (water and fat) is visualized while the calcific component is transparent. In the brain, MRI can differentiate between white matter and grey matter and can also be used to diagnose bleeds, aneurysms and tumors. Because MRI does not use x-rays, it is the imaging modality of choice when frequent imaging is required for making a diagnosis or monitoring therapeutic response and progression of disease.


All MRI machines are NOT the same. A High Field MRI machine employs a powerful magnet which produces a strong magnetic field 1.5T or greater that forces protons (Hydrogen Atoms) in the body to align with that field. When a radiofrequency current is then pulsed through the patient, the protons are stimulated, and spin out of equilibrium, straining against the pull of the magnetic field. When the radiofrequency field is turned off, the sensors in the MRI coils are able to detect the energy released as the protons realign with the magnetic field. The time it takes for the protons to realign with the magnetic field and the amount of energy released changes depending on the environment and the chemical nature of the water and fat molecules. Your doctors are able to tell the difference between various types of tissues based on these magnetic properties. Low Field MRI Machines, 1T or less will not produce the same image quality as a High Field MRI  and may make it more difficult for your doctor to make an accurate diagnosis.


To obtain an MRI image, the patient is placed inside the bore of a large magnet and is instructed to remain very still during the imaging process in order not to blur the image. Contrast agents (often containing the element Gadolinium) may be given to you intravenously before or during the MRI. This will allow your doctor to better differentiate tissue and structures.


Stacy Medical Center is the first and only exclusively industrial / occupational medical center in California to have a High Field MRI scanner located within their facility. Clinical studies show workers injured on the job that receive appropriate diagnostic tests and treatment without delay recover from their injury / illness sooner with less lost work time. Having a High Field MRI scanner within our facility allows us to adhere to our philosophy making it is possible to minimize our patients morbidity while reducing the overall cost of the workers' compensation claim.