A radiographic technique that employs motion to demonstrate anatomy lying in a plane of tissue while blurring or eliminating structures above and below the plane of interest
Method to overcome superimposition
Tomography
3 Elements
¤The x-ray tube
¤The patient (object/structure)
¤The image receptor
¨Based on the synchronous movement of two elements in a tomographic system
¤In opposite directions during exposure
¤Exposure produced from motion in 1 direction
Fulcrum
The object of interest is placed at the level of the fulcrum
Can be adjusted to different heights
Object at fulcrum will not be blurred
it hasn’t moved in relationship to tube and image receptor
The arrow remains at same position on image receptor
Circle and square streaked across entire length of image receptor
Tomographic Amplitude (ARC)
Also called tomographic arc or angle
¤the total distance the tube travels
The exposure does not need to be the entire tomographic amplitude