|
| |
CT scanning
Computed tomography
CT imaging uses X-rays in conjunction with computing algorithms to image the
body. In CT, an X-ray generating tube opposite an X-ray detector (or detectors)
in a ring shaped apparatus rotate around a patient producing a computer
generated cross-sectional image (tomogram). CT is acquired in the axial plane,
while coronal and sagittal images can be rendered by computer reconstruction.
Radiocontrast agents are often used with CT for enhanced delineation of anatomy.
Intravenous contrast can allow 3D reconstructions of arteries and veins.
Although radiographs provide higher spatial resolution, CT can detect more
subtle variations in attenuation of X-rays. CT exposes the patient to more
ionizing radiation than a radiograph. Spiral Multi-detector CT utilizes 8,16 or
64 detectors during continuous motion of the patient through the radiation beam
to obtain much finer detail images in a shorter exam time. With computer
manipulation these images can be reconstructed into 3D images of carotid,
cerebral and coronary arteries. Faster scanning times in modern equipment has
been associated with increased utilization.
| |
|
