Imaging Techniques - Chapter 3

For Your Reference - Box 3-5 - Chapter 3

cineradiography

making of a motion picture successive images appearing on a fluoroscopic screen

computed tomography (CT Scan)

use of a computer to generate an image from a large number of x-rays passed at different angles through the body; a three-dimensional image of a cross ection of the body is obtained; reveals more about soft tissues than does simple radiography

fluoroscopy

use of x-rays to examine deep structures; the shadows cast by x-rays passed through the body are observed on a fluorescent screen; the device used is called a fluoroscope

magnetic resonance imaging (MRI)

production of images through the use of a magnetic field and radio waves; the characteristics of soft tissue are revealed by differences in molecular properties; eliminates the need for x-rays and contrast media

positron emission tomography (PET)

production of sectional body images by administration of a natural substance, such as glucose, labeled with a positron-emitting isotope; the rays subsequently emitted are interpreted by a computer to show the internal distribution of the substance administered; PET has been used to follow blood flow through an organ and to measure metabolic activity within an organ, such as the brain, under different conditions

radiography

use of x-rays passed through the body to make a visual record (radiograph) of internal structures either on specially sensitized film or digitally; also called roentgenography after the developer of the technique

scintigraphy

imaging the radioactivity distribution in tissues after internal administration of a radioactive substance (radionuclide); the images are obtained with a scintillation camera; the record produced is a scintiscan and usually specifies the part examined or the isotope used for the test, as in bone scan, gallium scan

single-photon emission computed tomography (SPECT)

scintigraphic technique that permits visualization of a radioisotope’s cross-sectional distribution

ultrasonography

generation of a visual image from the echoes of high-frequency sound waves traveling back from different tissues; also called sonography and echography