 |
 |
Dear All In addition to some fat skin etc., the tpm for class 5 contains some of the major vessels: MCA, some of transverse sinus, sagittal sinus, some of Circle of Willis, and in SPM12 the straight sinus. There is actually quite a bit of difference between TPM,5 in SPM12 and the one form “new segmentation” in SPM8. I have tried to add a vessel only class based on a MP2RAGE with and without contrast. But this is a tricky class to fit as the intensity will wary greatly depending on the angle between B0 and the flow. I would be great if John could share some details about how these templates were created. Best Torben P.S. in the attached figure the intensity range was reduced to [0 0.5], and the SPM12 version is shown on top. 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 [log in to unmask] [log in to unmask] > Den 21/11/2014 kl. 22.16 skrev Chris Watson <[log in to unmask]>: > > The smaller vessels will probably be included in the GM TPM (maybe CSF for some). > > On 11/21/2014 05:04 AM, [log in to unmask] <mailto:[log in to unmask]> wrote: >> Hi Chris, >> >> Thank you for your reply. My original T1s have an isotropic 1mm resolution, and were taken with a 3T MR machine. >> >> I tried looking at the T1 and TPMs side by side and it seems like the bigger vessels (carotids and the bigger venous sinuses) are excluded. However I am not entirely sure about the smaller cerebral arteries. >> >> Cheers >> Robert >> >> From: Chris Watson [mailto:[log in to unmask] <mailto:[log in to unmask]>] >> Sent: Donnerstag, 20. November 2014 21:28 >> To: Terlevic, Robert; [log in to unmask] <mailto:[log in to unmask]> >> Subject: Re: [SPM] Do raw VBM volumes include the volume of the vascular space? >> >> It will probably depend on image quality & resolution. You may have to look at the original T1 and the TPM's side-by-side to see where the vascular tissue was included. >> >> On 11/20/2014 11:55 AM, Robert Terlevic wrote: >> Dear SPM community, >> >> I have an unusual question about VBM. Do any of the raw volume estimates (GM, WM, CSF) include the volume occupied by the vascular compartment, i.e. vessels big enough to show up on a scan? >> >> Thanks! >> >> Cheers, >> Robert >> >> > >