Hi - I'm afraid there's no simple rules on that.   I would expect SIENAX to be more affected by poor SNR than SIENA, because the latter concentrates on "global" calculations, and doesn't rely on voxel-level segmentation in the same way.

Steve.

On 3 Jan 2014, at 21:43, Amlish Munir <[log in to unmask]> wrote:

Hello Everyone,

I have a question regarding the signal to noise ratio. How would the ratio affect the final PBVC measurements? Also, in what step will the issues be most prominent? Obviously, the comparison would be between images that have a high or low signal to noise ratio.

Thanks for your input,

Amlish

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Stephen M. Smith, Professor of Biomedical Engineering
Associate Director,  Oxford University FMRIB Centre

FMRIB, JR Hospital, Headington, Oxford  OX3 9DU, UK
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