A PET scan produces images of metabolic activity as opposed to images of the body's physical structures that are derived from these other imaging tests. This is important because functional changes often predates structural changes in tissues. PET images may therefore demonstrate changes long before they would be revealed by modalities like CT and MRI.

Both MRI and CT scans make cross-sectional images (slices) of pretty much any area of the body using a sophisticated computer system. The major difference is that an MRI uses a large magnet and radio waves to produce images while a CT scanner uses x-rays. Therefore, with the MRI studies, there is no exposure to x-rays.

Computed Tomography (CT) uses x-rays to create a cross-sectional image of the body part being examined. Magnetic Resonance Imaging (MRI) uses a high field strength magnet and radio waves to generate a cross-sectional image.

CT and MRI differ in two basic ways.CT uses x-rays to detect and record the radiation absorbed by different tissues, and sends the data to a computer to transform into images. MRI does not use x-rays. Instead, MRI employs a powerful magnetic field to monitor the nuclei of hydrogen atoms in water, the most abundant element in the body.

For the first time, doctors will be able to simultaneously combine images with precision. Instead of taking separate CT and PET exams (where the patient’s anatomy could change alignment in the hours, weeks or months between exams) doctors will be able to perform one exam on Discovery, enabling them to more quickly and accurately view the locations of lesions.

PET produces images of metabolic activity as opposed to images of the body's physical structures that are derived from these other imaging techniques. Note the following example:

The studies are read shortly after the PET scan is completed and patients can expect verbal reports to be available to their physicians on the day of the study. Most insurance companies pay for clinically indicated PET procedures. To be clinically indicated, the PET scan must be potentially beneficial in providing information supportive of a diagnosis or monitoring certain conditions.

CT and MRI provide different kinds of information. Your doctor determines which is the most appropriate test for you, and sometimes both are necessary. While both scanners are similar in appearance, CT scanners make images is by using x-rays to plot the difference in electron density of adjacent tissues, and MR scanners, as described above, make images based on differences in the density and behaviour of hydrogen protons.

CT and MRI scans are anatomic imaging modalities, which means they look at the size and shape of organs and body structures. A PET scan is a metabolic imaging modality, which means it looks at function. The information collected from a PET scan is different from any other test that is available.

MRI scan is excellent at showing soft tissue such as spinal cord, nerve roots and herniated discs. A CT scan shows bone detail and some soft tissue. When looking for herniated discs or tumors, an MRI image will usually reveal much more detail.

MRI stands for Magnetic Resonance Imaging and does not utilize radiation. Instead, a strong magnetic field and radio waves are combined to create high-quality images of soft tissue which cannot be detected by an X-ray.

All four are useful for non-invasive medical imaging. X-rays Conventional X-ray images are usually on photographic film or a fluorescent screen. X-rays from an X-ray tube pass through the body and the difference in absorption by different structures in the body is what produces contrast in the images. The images are 2D projections of a 3D object so they contain overlapping structures.

One of the most basic differences between the two tests is that CAT Scanning uses x-rays and MRI does not. In most situations, MRI is superior to CAT in the demonstration of soft tissue pathology. Your doctor can best advise which test would be most appropriate for you.

A modern imaging center comprises a variety of diagnostic equipments for example plain radiography, ultrasonography, computed tomography, magnetic resonance imaging, angiography, etc...Each of these modalities has its own characteristic nature, and unique physical principle for image production. Each has its advantages, and indications relevant tot the organ being examined, disease process under investigation and patient concerned.

CT stands for Computerized Tomography, which refers to the way this exam is performed. In actuality, a CT scan is an x-ray procedure which is enhanced by a computer. This results in a three-dimensional view (referred to as a "slice") of a particular part of the body. During a routine x-ray, dense tissues can block other areas.

CT imaging itself is painless. The patient is required to remain motionless during the examination (which is difficult for some people), but the actual scan causes no bodily sensation.

CT and MRI scans are anatomic imaging modalities, which means they look at the size and shape of organs and body structures. Therefore, they can be useful in determining the size and location of a tumor; however, neither of them can determine whether a tumor is still active. A PET or PET•CT scan is a metabolic imaging modality, which means it looks at function. The information collected from a PET or PET•CT scan is different from any other test that is available. Here at St.