Thoracic CT – Tomography is a method of body imaging in which
the X-ray source and/or detection device (e.g., film) rotate around the
patient. In computed tomography (CT), a thin X-ray beam rotates as small
detectors measure the amount of X-rays which make it through the patient
or particular area of interest.
By use of a complex algorithm, a computer analyzes the data to construct
a cross-sectional (axial) image. These images can be stored, viewed on a
monitor, or printed on film. In addition, three-dimensional models of
organs can be created by stacking the individual images, or “slices.”
Alternative Names: CAT scan; Computed axial tomography (CAT) scan
How the test is performed: The patient will be asked to lie on a
narrow table (gantry) that slides into the center of the scanner.
Depending on the study being performed, the patient may need to lie on
his/her stomach, back, or side. If contrast media (dye) is to be
administered, an IV will be placed in a small vein of a hand or arm.
Much like standard photographic cameras, subject motion causes blurred
images in CT. Therefore, the technologist operating the scanner and
supervising the patient will give instructions through an intercom when
to hold one’s breath and not move.
As the exam takes place, the gantry will advance small intervals through
the scanner. Modern “spiral” scanners can perform the examination in one
continuous motion of the gantry. Generally, complete scans will only
take a few minutes, however, additional contrast-enhanced or
higher-resolution scans will add to the scan time. The newest
multidetector scanners can image the entire body, head to toe, in less
than 30 seconds.
CT stands for computerized tomography. In this procedure, a thin X-ray beam is rotated around the area of the body to be visualized. Using very complicated mathematical processes called algorithms, the computer is able to generate a 3-D image of a section through the body. CT scans are very detailed and provide excellent information for the physician.
Back to patient care page |
Services |
Patient forms |
Diagnostic tools |
Glossary |
Web resources |
Support groups |
Top of Page