Length Calculation in 3D reconstructed Images .

I have a CT series.
with 2D and 3D-reconstructed images ,
I can trivially get the length calculation to work for 2D images.
However, for 3D, my calculation proves to be totally wrong.

Is there any specific Dicom tag that I need to look for?
Any specific length calculation for 3D images that I need to use?
--
kris

kris108 wrote:[color=blue]
> I have a CT series.
> with 2D and 3D-reconstructed images ,
> I can trivially get the length calculation to work for 2D images.
> However, for 3D, my calculation proves to be totally wrong.
>
> Is there any specific Dicom tag that I need to look for?
> Any specific length calculation for 3D images that I need to use?[/color]

For cross sectional images, you should only need Image Position
(Patient) and Image Orientation (Patient).

HTH
Mathieu