Quick Start

ASHS Quick Start

This section is organized as a series of questions to help you get started with ASHS.

1. Pick the ASHS atlas that is best for your data

Most users will run ASHS using one of the existing atlases that we provide. However, for this to work, your MRI scans must be sufficiently similar to the MRI scans used to form the atlas. Currently, the following atlases are available for ASHS:

ASHS-PMC: Penn Memory Center T2-weighted 3T MRI Atlas

Use this atlas if:

  • Your MRI protocol includes
    • T2-weighted MRI of approximately 0.4 x 0.4 x 2.0 mm3 resolution, slices orthogonal to hippocampal main axis (see figure)
    • T1-weighted MRI of approximately 1.0 x 1.0 x 1.0 mm3 resolution
  • You wish to segment hippocampal subfields and extrahippocampal MTL subregions
  • You are studying older adults (studies of aging and early neurodegenerative diseases)

Input data and segmentation for the ASHS-PMC atlas

ASHS-PMC-T1: Penn Memory Center T1-Only Atlas for T1-weighted 3T MRI

Use this atlas if:

  • Your MRI protocol includes only whole-brain T1-weighted MRI (no high-resolution T2)
  • You wish to segment extrahippocampal MTL subregions (ERC, BA35, BA36 and PHC) and the whole hippocampus (only anterior/posterior, but not hippocampal subfields)
  • You are studying older adults (studies of aging and early neurodegenerative diseases)

Input data and segmentation for the ASHS-PMC-T1 atlas

ASHS-Utrecht: Utrecht Medical Center 7T MRI Atlas

Use this atlas if:

  • Your data is similar to the protocol described in [Wisse et al., 2016]

Build a Custom Atlas

If none of the atlases above suit your needs, you can build your own atlas. You will need:

  • MRI data from 20-30 representative subjects with manual segmentations
  • Access to a high-performance computing (HPC) Linux cluster

2. Verify that your MRI data is suited for ASHS

Check that your data meet the requirements for the atlas you choose:

3. Choose how to run ASHS

If you are using an existing atlas you can run ASHS in two ways:

If you are building a custom atlas, you will need to install ASHS on an HPC cluster