[Mristudio-users] Mesure FA from middle cerebelar peduncles

[susumu mori]

In general (not just for the middle cerebellar peduncle), there are several
ways for quantification strategy.

1) 2D manual ROI drawing: RoiEditor has very powerful user-interface for ROI
drawing. You can define the boundary based on your subjective judgement or
using threshold and region growing tools. Please refer to our video tutorial
(
https://www.mristudio.org/documentation/video/MristudioTutorialVideo/ROIEditor.htm)
about how to use RoiEditor for ROI definition. From somewhere around from
3:30, regular ROI drawing is explained and from around 10:30, strategies to
use threshold and region growing tools for more objective definition are
explained.

2) 3D manual ROI drawing: The above 2D ROI approach can be easily extended
to 3D ROIs using RoiEditor. This is also explained in the video tutorial.

3) Tractography: There are several reasons why you want to use
tractography-based tract definition.  First, it may save time. Second, it
provides an objective way to define a tract, although there is still
dependency on ROIs for tract extraction. Third, it has a potential to
delineate a tract that can not be done by manual ROIs. For example, the
cortico-spinal tract can't be identified discretely at the internal capsule
level because it is buried inside it together with many other tracts such as
thalamic fibers. By using tractography, you may be able to delineate where
is the CST inside the internal capsule with some degree of accuracy.
 Downside of tractogrpahy is, it could be less reproducible for test-retest
and inter-subject, making the standard deviations of normal subjects larger.

For tractography-based quantification, please see;
https://www.mristudio.org/documentation/video/MristudioTutorialVideo/Fiber.htm
<https://www.mristudio.org/documentation/video/MristudioTutorialVideo/Fiber.htm>At
around 15 min, an example of "good protocol" is explained and at 18 min,
"CUT" operation is explained, which may be suitable for your quantification
purpose.

On Mon, Sep 27, 2010 at 1:02 PM, Lucas Lessa <lucas_lessa at yahoo.com.br>wrote:

> Good afternoon,
>
> I tried to mesure the FA from middle cerebelar peduncles, but I got a
> significant difference between right and left.
> Now I want to mesure the FA from the entire middle cerebelar peduncles, not
> using ROIs as I was doing, but the entire tract.
> Is it possible?
> Thank you.
>
> Lucas Lessa.
>
>
> _______________________________________________
> mristudio-users mailing list
> mristudio-users at mristudio.org
> http://lists.mristudio.org/mailman/listinfo/
> Unsubscribe, send a blank email to:
> mristudio-users-unsubscribe at mristudio.org
>
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: http://lists.mristudio.org/pipermail/mristudio-users/attachments/20100930/b58bc872/attachment.html