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<DIV>Hi IPL Folks,</DIV>
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<DIV>Some of us have been left behind and are continuing to work while others are expanding their minds in Florence...</DIV>
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<DIV>We are working out parameters to achieve a high resolution scan for T1 and T2 for measuring brain structures. Our scanner is a Phillips 3T. I think we have a decent MPRAGE worked out, and the voxel size is .83 x .88 x 1.00. The best T2 we can acquire without artifact, however, has a voxel size of 1 x 1 x 1.5. We are acquiring in the sagittal plane (because it conforms with parameters of our concurrent fMRI study). </DIV>
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<DIV>My question is whether the T1 and T2 images must be of the same voxel size. If not, how different can they "safely" be and still achieve accurate measures?</DIV>
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<DIV>I have noticed in past protocols that the two voxel sizes may be slightly different (e.g., MR5). However, it's unclear to me how BRAINS2 would handle registration, tissue classification, and volumetric measurements if the two MR images have different voxel sizes. </DIV>
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<DIV>Any input on this would be greatly appreciated. </DIV>
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<DIV>thanks,</DIV>
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<DIV>--cherie</DIV>
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<DIV>Cherie L. Marvel, PhD<BR>Research Associate<BR>Johns Hopkins Medicine<BR>Department of Neurology<BR>Division of Cognitive Neuroscience<BR>1620 McElderry St., Reed Hall E-2<BR>Baltimore, MD 21205<BR>Tel: (410) 502-4664<BR>Fax: (410) 502-2189<BR><A href="http://www.jhu.edu/nimlab">www.jhu.edu/nimlab</A><BR></DIV></BODY></HTML>