Hello SPM Experts,
I have recently collected some segmentation data (modulated normalised) on about 29 of my subjects (age = 60 to 69). After calculating ICV (GM+WM+CSF) I calculated the percentage of each tissue type (GM/ICV), and my results yielded some interesting values. It appears as if my CSF volume makes up about 18 to 41% (mean = 32%) of total ICV (see values below). My question is related to the high percentage of CSF volume. Are these values what other people see? Is this a common finding in "older" healthy adults using this methodology? Also, if anyone would be able to suggest some literature I would greatly appreciate it. I found one paper describing 'normative' values in healthy adults (Kruggel-2006-MRI-based volumetry of head compartments: Normative values of healthy adults), but the methodology that was used is different. Any suggestions would be great.
Cheers!
CSF/TBV
0.369677793
0.316596805
0.250886675
0.343763644
0.362200567
0.319824008
0.34150398
0.323900256
0.39456022
0.3267729
0.273886916
0.255621697
0.347943037
0.297922525
0.349123208
0.315401937
0.386075517
0.186514505
0.384746976
0.275407774
0.304729
0.377143486
0.393461728
0.242075638
0.294585911
0.269121855
0.312448977
0.412999751
0.311132561
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