Why I would need Boundary Shift Integral or IPCA for computing whole-brain atrophy rates?
Hello all
I have seen in the articles:
-Freeborough, P.A., Fox, N.C., 1997. The boundary shift integral: an accurate and robust measure of cerebral volume changes from registered repeat MRI. IEEE Trans. Med. Imaging 16, 623- 629.
- Kewei Chen et. all. An automated algorithm for the computation of brain volume change from sequential MRIs using an iterative principal component analysis and its evaluation for the assessment of whole-brain atrophy rates in patients probable with Alzheimer's disease. NeuroImage 22 (2004)
That measures are obtained to estimate the whole-brain atrophy rates in patients with probable Alzheimer's disease and controls.
Can I get the same thing by using the calculated intracranial volume (whole-brain) obtained from freesurfer after Skull Streaping and computing the differences for these volumes for the sequential images?
Could these two analyses be equivalent in the sense that both they would give me whole-brain atrophy rates? So, if I have intracranial volume calculated why I would need BSI?.
I have the same doubt for hippocampus volume comparisons for sequential images. Can I use a volume calculated from freesurfer subcortical segmentation or again I will need BSI or some other measure?
In advance, thank you
Jorge
______________________________________________ LLama Gratis a cualquier PC del Mundo. Llamadas a fijos y móviles desde 1 céntimo por minuto. http://es.voice.yahoo.com
Hi Jorge,
probably not as the BSI is an intrinsicially longitudinal technique and so would have smaller error bars than treating the timepoints independently. We have some longitudinal tools (recon-all-long) that do something similar.
cheers, Bruce On Thu, 4 May 2006, jorge luis wrote:
Hello all
I have seen in the articles:
-Freeborough, P.A., Fox, N.C., 1997. The boundary shift integral: an accurate and robust measure of cerebral volume changes from registered repeat MRI. IEEE Trans. Med. Imaging 16, 623- 629.
- Kewei Chen et. all. An automated algorithm for the
computation of brain volume change from sequential MRIs using an iterative principal component analysis and its evaluation for the assessment of whole-brain atrophy rates in patients probable with Alzheimer's disease. NeuroImage 22 (2004)
That measures are obtained to estimate the whole-brain atrophy rates in patients with probable Alzheimer's disease and controls.
Can I get the same thing by using the calculated intracranial volume (whole-brain) obtained from freesurfer after Skull Streaping and computing the differences for these volumes for the sequential images?
Could these two analyses be equivalent in the sense that both they would give me whole-brain atrophy rates? So, if I have intracranial volume calculated why I would need BSI?.
I have the same doubt for hippocampus volume comparisons for sequential images. Can I use a volume calculated from freesurfer subcortical segmentation or again I will need BSI or some other measure?
In advance, thank you
Jorge
LLama Gratis a cualquier PC del Mundo. Llamadas a fijos y móviles desde 1 céntimo por minuto. http://es.voice.yahoo.com _______________________________________________ Freesurfer mailing list Freesurfer@nmr.mgh.harvard.edu https://mail.nmr.mgh.harvard.edu/mailman/listinfo/freesurfer
Hi, Pardon my stupidity, from what I understand of a previous email exchange by Jorge, I realised that one could obtain the values of TIV and TBV. May I know where will I be able to retrieve these values? Thanks! Kind regards, HweeLing
Hi, I was wondering where would I be able to find information regarding the longitudinal tools for freesurfer. I'm working on a dataset that was meant for a longitudinal study. For the first pass, we intend to report the cross-sectional results first. Would it be a good idea to start using the longitudinal tools even for the cross-sectional purpose and then proceed further to longitudinal report later? Thanks again. Kind regards, HweeLing
The longitudinal tools are still somewhat experimental and we are not distributing them yet. Check back in July.
doug
Lee HL wrote:
Hi, I was wondering where would I be able to find information regarding the longitudinal tools for freesurfer. I'm working on a dataset that was meant for a longitudinal study. For the first pass, we intend to report the cross-sectional results first. Would it be a good idea to start using the longitudinal tools even for the cross-sectional purpose and then proceed further to longitudinal report later? Thanks again. Kind regards, HweeLing
Freesurfer mailing list Freesurfer@nmr.mgh.harvard.edu https://mail.nmr.mgh.harvard.edu/mailman/listinfo/freesurfer
Hi HweeLing,
you can recon the first timepoint with the cross-sectional tools, as recon-all-long expects it.
Bruce On Thu, 4 May 2006, Lee HL wrote:
Hi, I was wondering where would I be able to find information regarding the longitudinal tools for freesurfer. I'm working on a dataset that was meant for a longitudinal study. For the first pass, we intend to report the cross-sectional results first. Would it be a good idea to start using the longitudinal tools even for the cross-sectional purpose and then proceed further to longitudinal report later? Thanks again. Kind regards, HweeLing
Freesurfer mailing list Freesurfer@nmr.mgh.harvard.edu https://mail.nmr.mgh.harvard.edu/mailman/listinfo/freesurfer
freesurfer@nmr.mgh.harvard.edu
-
Bruce Fischl -
Doug Greve -
jorge luis -
Lee HL