Hi all,
I am looking for an accurate method of calculating whole brain volume (WBV) from a spreadsheet of FS MRI data. I had previously been using the following method:
1. Sum the following: CSF, lateral ventricles, 3,4,5 ventricles, and the choroid plexus 2. In a second column, sum the following: cortical wm, cerebellar white matter, brain stem, and total gray volume. 3. Whole Brain Volume = 2 - 1
However, this method gave WBV values greater than that of the intracranial volume (ICV) for some participants. Removing brain stem from the equation did not make a big impact.
Is there a method to more accurately calculate WBV?
Additionally, I am looking for a way to calculate the amount of space in the ICV that is not occupied by the brain (the "gap" volume). I have been using the equation gap = ICV-WBV. Is there, however, a more accurate way to calculate the value of gap, possibly using the sum of the spaces in the brain rather than the difference between ICV and WBV?
Sincere thanks, Phil
-- Phillip J. Hsu Washington University in St. Louis hsup@wustl.edu