Hi - yes, use avwstats++ to get the std and mean within the ROI, and
then avwmaths++ to convert the FA to a Z using this.
Steve
On 12 Jan 2007, at 11:44, xu haibo wrote:
> Hi, Steve,
>
> Right. I want to convert an FA image into a Z image on the
> basis of similarity of voxel FA values to that mean and to use the
> stddev inside the ROI. How to do that? BTW, what is different if
> using the stddev across the image? Thanks.
>
> haibo
>> From: Steve Smith <[log in to unmask]>
>> Reply-To: FSL - FMRIB's Software Library <[log in to unmask]>
>> To: [log in to unmask]
>> Subject: Re: [FSL] How to calculate CC on the FA map
>> Date: Thu, 11 Jan 2007 17:26:04 +0000
>>
>> Hi,
>>
>> I think you're saying that you want to define an ROI within which
>> to estimate a mean FA value. You then want to convert an FA image
>> into a Z image on the basis of similarity of voxel FA values to
>> that mean. However, in order to do that you will also need to
>> define what standard deviation you want to use to form the Z. Do
>> you want to use the stddev inside the ROI, or across the image,
>> or maybe some other measure?
>>
>> Cheers.
>>
>>
>> On 11 Jan 2007, at 11:56, xu haibo wrote:
>>
>>> Hi, Steve,
>>>
>>> Thanks for your time for answering my question. I try to get a
>>> Z map where I can adjust the threshold to see the FA value of
>>> which voxel is close that of ROI on the FA map. Sorry for my
>>> poor english. Do I make myself clear? Thanks.
>>>
>>>
>>>> From: Steve Smith <[log in to unmask]>
>>>> Reply-To: FSL - FMRIB's Software Library <[log in to unmask]>
>>>> To: [log in to unmask]
>>>> Subject: Re: [FSL] How to calculate CC on the FA map
>>>> Date: Wed, 10 Jan 2007 16:34:21 +0000
>>>>
>>>> Hi - I'm sorry, I can't understand what you're asking here.
>>>> Please could you clarify what you are wanting to do?
>>>> Thanks.
>>>>
>>>>
>>>> On 7 Jan 2007, at 14:13, Haibo Xu wrote:
>>>>
>>>>> Hi, FSL experts,
>>>>>
>>>>> I want to calculate the correlation coefficient of the FA
>>>>> value each
>>>>> voxel referred to the FA value of ROI based on the FA map. If
>>>>> I define the
>>>>> ROI as the mass on the FA map, for example, then compare the
>>>>> FA value each
>>>>> voxel in the same brain volume to the FA value of ROI and try
>>>>> to get a CC
>>>>> map. In addition, to adjust the threshold to see which voxel
>>>>> is highly
>>>>> related to the ROI on the CC map. But I do not know to how to
>>>>> use FSL
>>>>> tools to get the CC map based on the FA map. Please tell me
>>>>> how to do it.
>>>>> Any suggestion or advice will be greatly appreciated.
>>>>>
>>>>> Haibo
>>>>
>>>>
>>>> -------------------------------------------------------------------
>>>> -- --- ---
>>>> Stephen M. Smith, Professor of Biomedical Engineering
>>>> Associate Director, Oxford University FMRIB Centre
>>>>
>>>> FMRIB, JR Hospital, Headington, Oxford OX3 9DU, UK
>>>> +44 (0) 1865 222726 (fax 222717)
>>>> [log in to unmask] http://www.fmrib.ox.ac.uk/~steve
>>>> -------------------------------------------------------------------
>>>> -- --- ---
>>>
>>> _________________________________________________________________
>>> 享用世界上最大的电å
>>> 邮件系统�MSN Hotmail� http://
>>> www.hotmail.com
>>
>>
>> ---------------------------------------------------------------------
>> --- ---
>> Stephen M. Smith, Professor of Biomedical Engineering
>> Associate Director, Oxford University FMRIB Centre
>>
>> FMRIB, JR Hospital, Headington, Oxford OX3 9DU, UK
>> +44 (0) 1865 222726 (fax 222717)
>> [log in to unmask] http://www.fmrib.ox.ac.uk/~steve
>> ---------------------------------------------------------------------
>> --- ---
>
> _________________________________________________________________
> Ãâ·ÑÏÂÔØ MSN Explorer: http://explorer.msn.com/lccn
------------------------------------------------------------------------
---
Stephen M. Smith, Professor of Biomedical Engineering
Associate Director, Oxford University FMRIB Centre
FMRIB, JR Hospital, Headington, Oxford OX3 9DU, UK
+44 (0) 1865 222726 (fax 222717)
[log in to unmask] http://www.fmrib.ox.ac.uk/~steve
------------------------------------------------------------------------
---
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