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[wiki:Self:FreeSurferWiki top] [[FreeSurferWiki|top]]
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!FreeSurfer is a freely available software package developed by investigators at the [http://www.nmr.mgh.harvard.edu: Athinoula A. Martinos Center for Biomedical Imaging] used for a number of procedures including: !FreeSurfer is a freely available software package developed by investigators at the [[http://www.nmr.mgh.harvard.edu:|Athinoula A. Martinos Center for Biomedical Imaging]] used for a number of procedures including:
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        1. Creation of computerized models of the brain from magnetic resonance imaging (MRI) data. [wiki:Self:FsTutorial/MorphAndRecon link]         1. Creation of computerized models of the brain from magnetic resonance imaging (MRI) data. [[FsTutorial/MorphAndRecon|link]]
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        2. Processing of functional magnetic resonance imaging (fMRI) data. [wiki:Self:FsFastTutorial link]         2. Processing of functional magnetic resonance imaging (fMRI) data. [[FsFastTutorial|link]]
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        3. Measuring a number of morphometric properties of the brain including cortical thickness and regional volumes. [https://surfer.nmr.mgh.harvard.edu/ftp/articles/fischl00-cortical-thickness.pdf link]         3. Measuring a number of morphometric properties of the brain including cortical thickness and regional volumes. [[https://surfer.nmr.mgh.harvard.edu/ftp/articles/fischl00-cortical-thickness.pdf|link]]
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        4. Intersubject averaging of structural and functional data using a procedure that aligns individuals based on their cortical folding patterns for optimal alignment of homologous neural regions. [https://surfer.nmr.mgh.harvard.edu/ftp/articles/fischl99-morphing.pdf link]         4. Intersubject averaging of structural and functional data using a procedure that aligns individuals based on their cortical folding patterns for optimal alignment of homologous neural regions. [[https://surfer.nmr.mgh.harvard.edu/ftp/articles/fischl99-morphing.pdf|link]]
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        The processing procedures for the creation of cortical models require good quality T1 weighted MRI data, such as a Siemens MPRAGE ([http://www.nmr.mgh.harvard.edu/~andre/ examples of appropriate Siemens scanner protocols]) or GE SPGR sequence with approximately 1mm^3^ resolution (although a variety of quality data sets can be processed with additional manual intervention). Thickness should not exceed 1.5mm (~1mm^3 is ideal). The best FreeSurfer processing results come from scans having excellent gray/white matter contrast.         The processing procedures for the creation of cortical models require good quality T1 weighted MRI data, such as a Siemens MPRAGE ([[http://www.nmr.mgh.harvard.edu/~andre/|examples of appropriate Siemens scanner protocols]]) or GE SPGR sequence with approximately 1mm^3^ resolution (although a variety of quality data sets can be processed with additional manual intervention). Thickness should not exceed 1.5mm (~1mm^3 is ideal). The best FreeSurfer processing results come from scans having excellent gray/white matter contrast.
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        [attachment:example_scans.tif Examples of different quality scans (click to download TIFF image):]         [[attachment:example_scans.tif|Examples of different quality scans (click to download TIFF image):]]
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        These example scans, captured from FreeSurfer's tkmedit display, are slices from the brainmask.mgz file, created by the -autorecon1 stage of FreeSurfer (requiring about 20 minutes of processing time). This means that some amount of intensity normalization has occurred, but the contrast differences between image examples are easier to see, compared to the original (orig.mgz) volume. Refer to the tutorial sections [wiki:Self:FsTutorial/ControlPoints 'Using Control Points to Fix Intensity Normalization'] and [wiki:Self:FsTutorial/WhiteMatterEdits 'Fixing Common Geometric Inaccuracies in White Matter Surfaces'] for examples of problem areas resulting from scan deficiencies.         These example scans, captured from FreeSurfer's tkmedit display, are slices from the brainmask.mgz file, created by the -autorecon1 stage of FreeSurfer (requiring about 20 minutes of processing time). This means that some amount of intensity normalization has occurred, but the contrast differences between image examples are easier to see, compared to the original (orig.mgz) volume. Refer to the tutorial sections [[FsTutorial/ControlPoints|'Using Control Points to Fix Intensity Normalization']] and [[FsTutorial/WhiteMatterEdits|'Fixing Common Geometric Inaccuracies in White Matter Surfaces']] for examples of problem areas resulting from scan deficiencies.
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        There is a variety of documentation about the use of FreeSurfer contained in the FreeSurfer wiki including [wiki:Self:DownloadAndInstall installation of the software], [wiki:Self:FsTutorial tutorials], [wiki:Self:FsTutorial/Data sample data], and [wiki:Self:WorkFlows work flows] providing step by step guides to performing specific tasks.         There is a variety of documentation about the use of FreeSurfer contained in the FreeSurfer wiki including [[DownloadAndInstall|installation of the software]], [[FsTutorial|tutorials]], [[FsTutorial/Data|sample data]], and [[WorkFlows|work flows]] providing step by step guides to performing specific tasks.
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              * [attachment:FSL_anatomical_stream.pdf slides 1 (BF)]
              * [attachment:fsintro.pdf slides 2 (DG)]
              * [attachment:fsrecon.pdf slides 3 (DG)]
              * [[attachment:FSL_anatomical_stream.pdf|slides 1 (BF)]]
              * [[attachment:fsintro.pdf|slides 2 (DG)]]
              * [[attachment:fsrecon.pdf|slides 3 (DG)]]
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            2. Read the background material: [wiki:Self:ArticlesSlidesAndPosters click here]             2. Read the background material: [[ArticlesSlidesAndPosters|click here]]
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            3. Install FreeSurfer: [wiki:Self:DownloadAndInstall click here]             3. Install FreeSurfer: [[DownloadAndInstall|click here]]
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            4. Download the sample data set: [wiki:Self:FsTutorial/Data click here]             4. Download the sample data set: [[FsTutorial/Data|click here]]
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            5. Follow the cortical reconstruction tutorial to create cortical models: [wiki:Self:FsTutorial click here]             5. Follow the cortical reconstruction tutorial to create cortical models: [[FsTutorial|click here]]
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An active [wiki:Self:FreeSurferSupport e-mail list] is available to answer specific questions about processing procedures. An active [[FreeSurferSupport|e-mail list]] is available to answer specific questions about processing procedures.
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There is also a [wiki:Self:UserContributions_2fFAQ FAQ] There is also a [[UserContributions_2fFAQ|FAQ]]

top

FreeSurfer Beginners Guide

FreeSurfer is a freely available software package developed by investigators at the Athinoula A. Martinos Center for Biomedical Imaging used for a number of procedures including:

  1. Creation of computerized models of the brain from magnetic resonance imaging (MRI) data. link

  2. Processing of functional magnetic resonance imaging (fMRI) data. link

  3. Measuring a number of morphometric properties of the brain including cortical thickness and regional volumes. link

  4. Intersubject averaging of structural and functional data using a procedure that aligns individuals based on their cortical folding patterns for optimal alignment of homologous neural regions. link

Machine Requirements

  • To run FreeSurfer, you will need either a PC running Linux or a Macintosh running OS X.

    FreeSurfer consumes a lot of processor time, memory resources and disk space, so it is recommended to run FreeSurfer on as powerful a machine as you have available. For example, at MGH we typically run Linux CentOS 4 on 2.5GHz dual processor AMD Opterons with 4 to 8 GB of DDR SDRAM, and 250GB of disk space.

    See SystemRequirements for more info.

Data Requirements

  • The processing procedures for the creation of cortical models require good quality T1 weighted MRI data, such as a Siemens MPRAGE (examples of appropriate Siemens scanner protocols) or GE SPGR sequence with approximately 1mm3 resolution (although a variety of quality data sets can be processed with additional manual intervention). Thickness should not exceed 1.5mm (~1mm^3 is ideal). The best FreeSurfer processing results come from scans having excellent gray/white matter contrast.

    Examples of different quality scans (click to download TIFF image):

    • A - excellent GM/WM contrast, acquired with MP-RAGE pulse-sequence protocol

    • B - very good GM/WM contrast, acquired with MP-RAGE pulse-sequence protocol

    • C - good GM/WM contrast, acquired with SPGR pulse-sequence protocol; not as good GM/WM contrast as the MP-RAGE acquisitions; low bandwidth causes some temporal lobe artifacts (brightening of the gray matter)

    These example scans, captured from FreeSurfer's tkmedit display, are slices from the brainmask.mgz file, created by the -autorecon1 stage of FreeSurfer (requiring about 20 minutes of processing time). This means that some amount of intensity normalization has occurred, but the contrast differences between image examples are easier to see, compared to the original (orig.mgz) volume. Refer to the tutorial sections 'Using Control Points to Fix Intensity Normalization' and 'Fixing Common Geometric Inaccuracies in White Matter Surfaces' for examples of problem areas resulting from scan deficiencies.

Getting Started

An active e-mail list is available to answer specific questions about processing procedures.

There is also a FAQ

FreeSurferBeginnersGuide (last edited 2020-04-10 10:31:15 by LeahMorgan)