Hi,
Thank you very much for your comments.
I re-calculated the lesion volume using both FSL and MEDx. below, I used
only one data set as comparing data.
I compared the volume value by using same partial volume maps.
Using FSL avwstats program for partial volume maps(lesion)
(*_brain_pve_0.img) segmented by FSL.
volume= 152450.286 (mm*mm*mm) *
Using Medx measurement tool for partial volume maps(*_brain_pve_0.img)
segmented by FSL, adds up the volumes with higher pixel value.
volume(mm*mm*mm) Lthreshold:pixel(mm)
160932 0.40
155287 0.42
152650 0.43 *
147495 0.45
136155 0.495 **
134997 0.5
It shows that value(152650) with pixel value(0.43) is comparable with the
value(152450) from avwstats.
I wonder if there is a Lthreshold already in avwstats program. Otherwise it
could be very different.
I also tried using segmentation maps(*_brain_seg.img) that segmented by fsl
as 4 classes. The 4th class is considered as lesion class. Then add up only
the 4th class volumes by MEDx.
volume= 136255 (mm*mm*mm) **
This is also a very statiable value, it is not depends on person who did
the measurement. I think it's supposed to be the same as the avwstats
value. But why it is so different with it. Could you give me some idea on
it?
additional, I tried using the original brain volumes(E*S*Iall.img), adds up
the partial volumes with higher pixel value.
volume(mm*mm*mm) Lthresholds:pixel(mm)
168745 125
152176 127 *
137790 129 **
131050 130
Looking forward to hearing the idea from you. Thanks.
(If you need the data set that I used, please let me know. I will try to
send to you).
Best Regards,
QingYan Guan
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