Hi All,
I have an interesting problem regarding registering an ROI back into native patient space. I have a symmetrical skeleton and average FA map produced by tbss for 18 patients and I have identical ROI's on the left side and right sides of the brain (made of voxels only in the symmetrical skeleton). After I run the following:
tbss_deproject grot_L 1
tbss_deproject grot_R 1
tbss_deproject grot_L 2
tbss_deproject grot_R 2
where grot_L and grot_R are the individual Left and Right masks that are identical sized mirror images of each other. After this, the masks are in native subject space. After running an analysis comparing the mask size in native space however, it returns that the L masks are smaller than the R mask fairly consistantly across all patients, averaging a 31% difference across all subjects. Anyone have any knowledge on why this could be happening? The following are the data of mask size in voxels:
L mask R mask
41 60
42 43
36 64
33 64
30 43
43 44
34 57
28 39
49 58
30 45
28 46
32 42
40 49
41 66
44 58
48 54
40 60
42 43
L avg = 37.83333333 R avg = 51.94444444
percent diff 31.43564356
Best,
Mike DiSano
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Michael DiSano
MSI, Research Assistant
Department of Neurosurgery
UT Medical School at Houston
6431 Fannin St MSB G.550D
Houston TX 77030
phone: 713-500-5475
fax: 713-500-0723
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