Hello,
There was a right/left question on the list for the FMRI analysis
contest (FIAC) data.
Thanks to the marseille center, we have now put on the web an anatomical
image with a visible landmark on the right :
http://www.madic.org/fiac/how_to_participate.html#data_format
This may be useful generally to check the display convention
best
jb
John Ashburner a écrit :
>>This e-mail won't be quite as easy as the last. Sorry. Because I've also
>>been having trouble with the orientation of our fMRI images, I've been
>>following these e-mails (specifically about image orientation). Can you
>>please tell me what LPI and RPI are?
>>
>>
>
>LPI is left, posterior, anterior, and RPI is right, posterior, inferior. The
>first element (L or R in this case) indicates the fastest changing direction
>within the file. The last element (I in this case) indicates the slowest -
>i.e. the way that the planes of data are stored.
>
>Best regards,
>-John
>
>
>
>>Quoting John Ashburner <[log in to unmask]>:
>>
>>
>>>>after John's emails I'd like to be sure about a couple of things.
>>>>1- What matters for flipping is the handness of storage, is that
>>>>correct?
>>>>
>>>>
>>>Yes.
>>>
>>>
>>>
>>>>2- Data stored in Right hand system needs not to be flipped, while Left
>>>>hand stored data need to be flipped.?
>>>>
>>>>
>>>Yes.
>>>
>>>
>>>
>>>>3- To tell the handnees of the actual
>>>>data, John suggested to look at voxel (1,1,1) for axial images. Now if
>>>>voxel (1,1,1) is LPI my data are right hand and need not to be flipped
>>>>in x dimension. is that correct?
>>>>
>>>>
>>>Yes.
>>>
>>>
>>>
>>>>If voxel (1,1,1) is RPI data need to be flipped
>>>>in x dimension. is that correct?
>>>>
>>>>
>>>Yes.
>>>
>>>
>>>
>>>>thanks for any help
>>>>
>>>>
>>>That was easy.
>>>
>>>best regards,
>>>-John
>>>
>>>
>
>
>
>
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