[Insight-users] Proton Density/T2-weighted images

Luis Ibanez luis.ibanez at kitware.com
Mon, 05 Jan 2004 16:38:20 -0500


Hi Radhika,

About your questions:

1) This sounds like a byte swapping problem.  It is likely that you are 
moving
    data from a platform with big-endian architecture to another one with
    little-endian architecture.

     What format are your original images on ?

    If you were using the MetaImage format, it is pretty easy to switch the
    endianess by just changing the header entry ElementByteOrderMSB.


2) Yeap, the easy way is to use MRIConvert:

            http://lcni.uoregon.edu/~jolinda/MRIConvert


   from Jolinda Smith at the Lewis Center for Neuroimaging 
<http://lcni.uoregon.edu/>
   at the University of Oregon <http://www.uoregon.edu/>.


    Read your series using this application and identify the
    DICOM fields that differentiate your T2 from PD datasets.
   
    Once you identify the fields, you can use this information
    for creating a new  DICOMSeriesFileNames class (of
     course named differently).

    Note also that you can simply save the data from MRIConvert,
   into Analyze or MetaImage format.


Regards,


    Luis

------------------------------------
Radhika Sivaramakrishna wrote:

> Hi Luis,
>
> I have two questions:
>
>  
>
> 1)       I tried to use the code you had sent me previously to read a 
> series image and save as Analyze format. Unfortunately although the 
> original images are of type which can definitely be supported by 
> unsigned short, the output image looks totally scrambled up. If I 
> change pixel type to unsigned char, then the image looks okay but I 
> lose all the high values and that's obviously visible. Could you tell 
> me what the problem might be?
>
> 2)       I have a large number of double spin echo images where the 
> shorter echo is PD and larger is T2-weighted. I want to extract only 
> the T2-weighted. They are part of the same series. I know that in the 
> software guide you have used a lot of PD/T2-weighted examples, so 
> there must be a way to extract this. With DicomSeriesFileName I see 
> that you can sort by ImageNumber, Image Position or Slice Location. 
> Unfortunately none of these will help sort T2 from PD. Is there a 
> better way to do this?
>
>  
>
> Thanks
>
> Radhika
>
>  
>
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