Dear Babu
I am afraid that I know of no philips scanners which can acquire 35 slices in 2 seconds with an TE of 45 ms. One bizarre thing about the Philips systems is that they will not tell you that you cannot fit 35 slices in a TR of 2s, instead it will create another slice group (i don’t remember what the philips name for this is), and while each group could then have a TR of 2s, the time from one slice is acquired until it is sampled again is 2*TR, which is the "Volume interval (s): 4" in your list of parameters. Only if the volume interval is the same as the Repetition time, can you assume that the scan time divided with the number of volumes is the TR.
Best
Torben
Torben Ellegaard Lund
Associate Professor, PhD
Center of Functionally Integrative Neuroscience (CFIN)
Aarhus University
Aarhus University Hospital
Building 10G, 5th floor, room 31
Noerrebrogade 44
8000 Aarhus C
Denmark
Phone: +45 7846 4380
Fax: +45 7846 4400
http://www.cfin.au.dk
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> Den 13/05/2015 kl. 09.23 skrev Babu <[log in to unmask]>:
>
> Dear Members,
>
> I have few basic questions. I am using Philips 1.5T for rsfMRI. I have scanned a subject for 8 min. I have given the details of aquisition parameters below. When TR is 2sec and scan time is 8 min (480 sec) the total volume should be 240. But I am getting only 120 volumes of images. Could you plz explain where I am going mistake or any other parameter affecting the scan time?
>
> "Repetition time (ms): 2000
> Echo time[0] (ms):
> Echo time[1] (ms): 45
> Inversion time (ms):
> Flip angle: 70
> Number of averages: 1
> Slice thickness (mm): 4
> Slice spacing (mm): 4
> Image columns: 64
> Image rows: 64
> Number of frames:
> Phase encoding direction: COL
> Voxel size x (mm): 3.4375
> Voxel size y (mm): 3.4375
> Number of volumes: 120
> Number of slices: 35
> Number of files: 4200
> Number of frames: 0
> Slice duration (ms) : 0
> Volume interval (s): 4
> Orientation: tra"
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