Hi Patrick,
if you are scanning at room temperature, I’d recommend trying to get higher than that (~ 4000 s/mm^2). This is just to make sure that you’ll have enough contrast to probe anisotropy in the tissue sample.
Have a look at these two articles that contain useful tips to setup ex vivo scans:
https://www.ncbi.nlm.nih.gov/pubmed/20945352
https://www.ncbi.nlm.nih.gov/pubmed/17292630
There are no issues, the DT fitting routine will be the same that you use for in vivo data. And an ex-vivo b-value ~=2000 s/mm^2 correspond to a lower b-value in vivo.
Hope this helps, cheers,
Matteo
> On 6 Jul 2017, at 18:25, Patrick <[log in to unmask]> wrote:
>
> Hello Experts
>
> I'm working on some ex-vivo diffusion measurements in rodents at 9.4 Tesla and I was wondering if anyone had answers to a few questions.
>
> Is it necessary to push the b-values high if we are only interested in cross sectional analysis with other ex-vivo brains? Obviously the values would be different than in-vivo scans but if the contrast is high enough and we aren't comparing with in-vivo brains is there any need to push the b-value up to 2000 or higher?
>
> Are there any issues with the reconstruction of FA and MD maps through FSL for fixed tissue if I do use a higher b-value (say 2000)?
>
> Thanks in advance
> Patrick
|