MNI SISCOM: an Open-Source Tool for Computing Subtraction Ictal Single-Photon Emission CT Coregistered to MRI


Subtraction ictal single-photon emission computed tomography (SPECT) coregistered to MRI (SISCOM) is a well-established technique for quantitative analysis of ictal vs interictal SPECT images that can contribute to the identification of the seizure onset zone in patients with drug‐resistant epilepsy. However, there is presently a lack of user-friendly free and open-source software to compute SISCOM results from raw SPECT and MRI images. We aimed to develop a simple graphical desktop application for computing SISCOM. MNI SISCOM is a new free and open-source software application for computing SISCOM and producing practical MRI/SPECT/SISCOM image panels for review and reporting. The graphical interface allows any user to quickly and easily obtain SISCOM images with minimal user interaction. Additionally, MNI SISCOM provides command line and Python interfaces for users who would like to integrate these features into their own scripts and pipelines. MNI SISCOM is freely available for download from:

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Author information




JTM: conception and design, app development, figures, drafting the manuscript, critically revising the manuscript. CSM: supervision, critically revising the manuscript. SB: supervision, funding and administration, critically revising the manuscript. RWRD: conception and design, supervision, drafting the manuscript, funding and administration, critically revising the manuscript.

Corresponding author

Correspondence to Jeremy T. Moreau.

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The authors declare that they have no conflict of interest.

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This study received full approval by the McGill University Health Centre’s Research Institute Ethics Board, and all involved patients and/or parents/guardians signed an informed consent form to be enrolled in the study.

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Moreau, J.T., Saint-Martin, C., Baillet, S. et al. MNI SISCOM: an Open-Source Tool for Computing Subtraction Ictal Single-Photon Emission CT Coregistered to MRI. J Digit Imaging (2021).

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  • Epilepsy
  • MRI
  • Software
  • Open-source
  • Python
  • Nuclear Imaging
  • Functional Neurosurgery