Editing Scanco Administration (section)

===Understand "New" DT functions in IPL v5.42===

This applies to:
<pre>/distance_map              /dt_ow_thickness           /dt_number                
/dt_thickness              /dt_spacing                /dt_cortical_thickness
</pre> 

XT1 (old dt) and XT2 (new dt) use 0.5 for assign_epsilon and 0.9 for
ridge_epsilon.

µCT uses 1.8 for assign_epsilon and 0.9 for ridge_epsilon (old dt).

Therefore I recommend to take 0.9 and 1.8 also for the new dt functions
for µCT/vivaCT measurements.

The <code>suppress_boundary</code> feature is new and works as follows:

0: The ridges and spheres are calculated on the full seg AIM, also
outside the gobj. At the end the gobj is applied.

1: The ridges that are on the AIM boundary are not used for the
calculation of the maximal spheres.

2: The ridges are calculated on the full seg aim but then the gobj is
applied to the ridges. This means that at the end there are only spheres
that have the center inside the structure (gobj). The maximal sphere
filling algorithm still accounts for the structure outside the gobj, but
only uses center points inside the gobj.


<code>dt_thickness</code> for example can be used in two different ways in a script:

1) cut out aim - apply threshold - apply gobj - dt_thickness
This way the suppress_boundary options do influence the results
because there are no ridges outside the gobj anyway.

2) cut out aim - apply threshold - dt_thickness (with corresponding gobj)
This calculates the dt on the full aim first and applies then the
gobj and suppress options.

If you examine for example trabecular bone only on a small area bounded
by a gobj then the most accurate way to calculate the dt is to cut out a
much larger area (still containing trabecular bone) and use way 2) above
with suppress_boundary 0.


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