Tomographic Exposure Programs - Planmeca ProMax X-ray User Manual

PROGRAMS
5.4

Tomographic exposure programs

Tomography
5.4.1 Tomographic exposure programs
Cross-sectional tomographic exposure programs
4x CRS Manual
Manual, 1-4 cross-sectional images. The operator can make
manual adjustments between the exposures.
20 ProMax X-ray unit with Dimax3
Transtomography
NOTE
Layer thickness, mm
Layer separation
Exposure time/frame, (sec.)
Patient dose
There are two tomography methods available: digital
tomography and digital transtomography.
Digital tomography uses one sweep method. The narrow
X-ray beam makes one sweeping movement and the
rotation centre moves simultaneously along the image
layer. The layer thickness is always 6mm.
Digital transtomography uses multiple sweep method.
During the transitional movement along the image layer
the X-ray beam makes also pendular movement back and
forth. The layer thickness can be adjusted.
Vertical artefacts, caused by high contrast
anatomies outside the layer, may occur in
transtomography when 1mm layer thickness is
used. Select a thicker layer to avoid this.
Digital tomography
6
Worse
3
Lower
Patient positioning in both systems is exactly the same
but the recommended exposure values are different.
The tomographic programs produce exposures of any
part of the maxillo-facial region. The tomographic
exposures can be cross-sectional, longitudinal or mixed.
In each program the user can select target area, patient
size and movement between the layers. The layer
thickness is adjustable in transtomography mode. You
can select a layer thickness of 1, 3, 6, 9, 18 or 36mm.
Transtomography
1, 3, 6, 9, 18, 36
Better
24
~
Higher ( 2x)
4xCRS_Manual.eps
User's Manual