Hi Gonzalo,

it is possible to run those tools on that data. The problem is you will never know if the effect you find is due to anatomical changes or scanner / field strength differences. Maybe you could scan 10-20 controls on the 1.5 and 3 T scanner back to back , to estimate scanner effects (using the assumption that anatomical changes are close to zero, which of course could be wrong, as there will be motion and hydration effects. Both could be affected by the order of scans, so I would randomly select which scan is done first (1.5 or 3T). Anyway with that data you could compare your effect with the test-retest scanner effect to see if there are significant differences.

Best, Martin

On 11/03/2015 07:41 PM, Gonzalo Rojas Costa wrote:

Hi:

I have two timepoints of the same patient: the first is in 1.5T and the second in 3.0T... Is it possible to do the longitudinal study (subcortical volumes) using the Workflow Summary described in https://surfer.nmr.mgh.harvard.edu/fswiki/LongitudinalProcessing ?...

Sincerely,

Gonzalo Rojas Costa

--
Gonzalo Rojas Costa
Laboratory for Advanced Medical Image Processing
Department of Radiology
Clínica las Condes
Lo Fontecilla 441, Las Condes, Santiago, Chile.
Tel: 56-2-2105170
Cel: 56-9-97771785
www.clc.cl

------------------------------------
Gonzalo Rojas Costa
Laboratory for Advanced Medical Image Processing
Department of Radiology
Clinica las Condes
Lo Fontecilla 441, Las Condes, Santiago, Chile
Tel: 56-2-2105170
Cel: 56-9-97771785
www.clc.cl
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-- 
Martin Reuter, PhD
Assistant Professor of Radiology, Harvard Medical School
Assistant Professor of Neurology, Harvard Medical School
A.A.Martinos Center for Biomedical Imaging
Massachusetts General Hospital
Research Affiliate, CSAIL, MIT
Phone: +1-617-724-5652
Web  : http://reuter.mit.edu