Thanks, I will try that!
Will the WMH borders be still easy to define after resampling the FLAIR to
1x1x1mm (is this what you mean by re-slicing?)?
Best,
Aga
On 18.03.2008 16:45 Uhr, "Peter Kochunov" <[log in to unmask]> wrote:
> I think you should have little troubles registering two datasets. One step
> you can do to insure stability is reslicing the FLAIR data into 1x1x1
> resolution before regestering it to T1w. Also you might want to play with
> the cost function in flirt. The normalized correlation don't seem to work as
> well as say mutual info.
> pk
> ----- Original Message -----
> From: "Agnieszka Burzynska" <[log in to unmask]>
> To: <[log in to unmask]>
> Sent: Tuesday, March 18, 2008 10:39 AM
> Subject: Re: [FSL] White matter hyperintensity and FLAIR processing
>
>
>> Dear Peter,
>> Thank you a lot for your email.
>> I can do without the automation (will do manual identification of affected
>> tissue), but I would like to have my FLAIR images in the MNI space. Do you
>> know if anyone does such registration with 5mm slice thickness? I know you
>> had 1mm isovoxel in your recent study and others with my parameters just
>> do
>> manual tracing on FLAIR image + multiply by slice gap to get the WMH
>> volume.
>>
>> Do you know if I will get this registration well in FLIRT and my MPRAGE or
>> shall I use a 1x1x1 T1-WI of these subjects (I may get them, but acquired
>> in
>> different MRI session- or will it cause even more problems with my FLAIR
>> quality?). I am not too familiar with FLIRT yet.
>>
>> Thanks a lot,
>> Aga
>>
>>
>> On 18.03.2008 14:33 Uhr, "Peter Kochunov" <[log in to unmask]> wrote:
>>
>>> Aga,
>>>
>>> Unfortunatly, I don't think automated processing will be possible with
>>> this
>>> dataset. The only workable approach to do automated HWM lesion
>>> segmentation
>>> is by the use of T2-maps produced by the multi-echo sequences.
>>> pk
>>> ----- Original Message -----
>>> From: "Agnieszka Burzynska" <[log in to unmask]>
>>> To: <[log in to unmask]>
>>> Sent: Tuesday, March 18, 2008 7:09 AM
>>> Subject: [FSL] White matter hyperintensity and FLAIR processing
>>>
>>>
>>>> Dear all,
>>>> I am searching for the most straightforward way to estimate the WMH load
>>>> in
>>>> my subjects.
>>>> 1) Was there any follow-up on the message from 2002? (see below)
>>>> 2) My FLAIR images have resolution 1.3x0.9x5mm and my MPRAGE 2x2x1mm.
>>>> Does
>>>> it mean I will have hard time in registering them to MNI?
>>>>
>>>> Thank you!
>>>>
>>>> Aga
>>>>
>>>>
>>>> On Mon, 22 Jul 2002, Wei Wen wrote:
>>>>
>>>>> Dear Steve,
>>>>>
>>>>> It may be possible to extract (segment) white matter hyperintensity
>>>>> (FLAIR
>>>>> sequence) using a combination of bet, fast etc. as discussed at FSL
>>>>> course
>>>>> in Melbourne. Could I send you a couple of such images and see if you
>>>>> could
>>>>> tweak the programs (or come up with some suggestions) for this purpose?
>>>>>
>>>>> Many thanks,
>>>>>
>>>>> Wei Wen
>>>>> NPI, Prince of Wales Hospital/UNSW
>>>>> Australia
>>>>>
>>>>>
>>>>
>>
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