Lesions in MS belong to at least three categories if one would rule out regions with potential accumulation of "non-heme" iron or micro-calcification that would make T1w bright: (1) GAD-enhancing, (2) T1-balckholes and (3) T2 hyperintense, majority of lesions. These may not have idential lesion distribution (see Lee Brain 2000 paper and hundreds of works on MS lesions; Hasan et al 2011; Hasan et al. 2012). You need FLAIR contrast to help identify the T2w-bright lesions as CSF intensity will be a confounder in segementation. I do not think T1w and T2w alone or even PD/T1 and T2 relaxation have optimal contrast and literature showed that FLAIR or double IR are a must to use in combination with T1/T1w or T2w/T2 and PDw/PD contrast. Thus in principle, in my experience SPM may be used for lesion segmentation but I rather utilzie it for spatial normalization, but must have all contrast data co-registered including FLAIR and some good training set. Hope this will help.
Khader M Hasan, PhD
Associate Professor of Radiology
MSE 168, Tel 713 500 7690 (FAX 713 500 7684)
University of Texas Health Science Center at Houston
Medical School
Diagnostic and Interventional Imaging
Magnetic Resonance Imaging Research Division
Diffusion Tensor Imaging Lab, Tel 713 500 7683
http://www.uth.tmc.edu/radiology/faculty/khader-m-hasan/index.html<http://www.uth.tmc.edu/radiology/faculty/hasan.html>
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From: SPM (Statistical Parametric Mapping) [[log in to unmask]] On Behalf Of Baali Cherif Billel Hamza [[log in to unmask]]
Sent: Wednesday, November 07, 2012 8:36 AM
To: [log in to unmask]
Subject: [SPM] Hi
Hello, I am working on a graduation project "Segmentation of lesions (multiple sclerosis)." My tool is SPM8: I make a readjustment intra-patient readjustment and ATLAS static and have also used a torque histogram intensity / voxel "T1, T2."
My problem is that nothing works I could not make readjustments and histogram also, I read the manual and I followed lès but without success.
I joined the histogram I want to get, I hope to have a response from you.
Cordially.
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