dear All,
using SIENA, I am trying to figure out the impact of the use of the
options -f .
I have calculated one examination with default f (f=0.5), f=0.4 and
f=0.3 (019-003a.jpg). The objective was to better include cortical gyri
(a), which were not caught by the default.
The objective was reached, but in turn new problems arose (b): a sulcus,
which was initially tracked disappeared. Also, other non-brain areas as
bone marrow (c in 019-003b.jpg) and clivus were included into the
segmentation.
With the different f-options the PBVC changed markedly:
f=0.3: -1.2%
f=0.4: -1.4%
f=0.5: -2.05%
in other examinations we observed a similar trend: with smaller f the
PBVC got also smaller.
how can these changes in PBVC be explained?
why is the edge detection inside the areas covered by bet different ?
is there a recommendation for using options in between-subject
comparison, should it be always the same options?
thanks for your input!
Martin
Dr. Martin Hardmeier
Department of Neurology
University Hospital Basel
Petersgraben 4
4031 Basel
Switzerland
Tel: 0041-61-2652525; pager -2913
Fax: 0041-61-2654100
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