---------- Forwarded message ---------- From: youngmin huh ymin1123@gmail.com Date: 2012/11/14 Subject: Re: bad acquisition and noise problem. To: Bruce Fischl fischl@nmr.mgh.harvard.edu

Thanks for your comment. I would appreciate if you could take a look. Do you want a whole folder of the subjects, or just 001.mgz and log file?

Thanks,

Youngmin.

2012/11/14 Bruce Fischl fischl@nmr.mgh.harvard.edu

it's not a question of SNR, the problem appears to me to be that the B0 distortions are so bad that a bunch of the temporal lobe is piled up on top of itself. There's no way to fix that posthoc. If you upload the full volume I'm happy to take a look

On Wed, 14 Nov 2012, youngmin huh wrote:

I'm not engaged in obtaining images, so I don't have any details about the

...

images.I wonder the method which you commented can be applied to images I

already earned. If it's not, is there any way to recover SNR after image scanning?

Thanks,

Youngmin Huh.

2012/11/13 Bruce Fischl fischl@nmr.mgh.harvard.edu what is the bandwidth? The typical way to fix it is to increase the bandwidth. You can probably recover some of the SNR you will lose by reducing your flip angle, which is pretty far from the Ernst angle. Also, minimize your TE (if 4ms is not already the min) cheers Bruce

  On Tue, 13 Nov 2012, youngmin huh wrote:

        Hi,
        3D SPGR sequences were used. (TR=22, TE=4,
        thickness=1.4, FOV=240*240,
        FA=40)
        If the artifacts are due to B0 distortion, I wonder
        how I can fix it.

        Thanks,
        Youngmin Huh



        2012/11/12 Bruce Fischl <fischl@nmr.mgh.harvard.edu>
              Can you give us the acquisition details? I
        suspect this is not
              noise, but rather B0 distortion.
              what is the acquisition? And what bandwidth?


              On Nov 8, 2012, at 2:53 AM, youngmin huh
        <ymin1123@gmail.com>
              wrote:

              > Dear all,
              >
              > I'm working with some images, and they have
        so much noises on
              temporal areas.
              > I just ran recon2, but not sure if they'll
        be segmented
              properly.
              > Does anyone have a recommendation for
        dealing with it?
              > I wonder if there is any flag or option for
        this occasion.
              > I would appreciate any comments or help.
              > I attached an example.
              >
              > Thanks,
              >
              > Youngmin Huh
        > <temporal_001.jpg>


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