Difference between revisions of "Documentation/4.8/Modules/GeodesicSlicer"
From Slicer Wiki
| Line 67: | Line 67: | ||
Run the Dijkstra's algorithm to make the 10-20 system electrode distances. | Run the Dijkstra's algorithm to make the 10-20 system electrode distances. | ||
| − | + | =4 anatomical landmarks= | |
# Source points: The list of fiducial points on the curve, since the "Create-and-place Fiducial" button (in green in the figure above). Four anatomical landmarks are used for the essential positioning of the electrodes (in this order!): | # Source points: The list of fiducial points on the curve, since the "Create-and-place Fiducial" button (in green in the figure above). Four anatomical landmarks are used for the essential positioning of the electrodes (in this order!): | ||
| + | [[File:4 landmarks.png|thumb|right|Four anatomical landmarks are used for the essential positioning of the electrodes: the nasion, the inion, the pre auricular to the left ear and the pre auricular to the right ear. ]] | ||
#* 1/the nasion | #* 1/the nasion | ||
#* 2/the inion | #* 2/the inion | ||
| − | |||
#* 3/the pre auricular to the left ear | #* 3/the pre auricular to the left ear | ||
#* 4/the pre auricular to the right ear | #* 4/the pre auricular to the right ear | ||
Revision as of 13:41, 9 March 2018
Home < Documentation < 4.8 < Modules < GeodesicSlicer
|
For the latest Slicer documentation, visit the read-the-docs. |
Introduction and Acknowledgements
|
The module has been developed based on ideas and feedback from the community. We would like to especially thank:
- Dr. Olivier Etard, M.D., Ph.D., CHU de Caen.
- Dr. Sonia Dollfus, M.D., Ph.D., CHU de Caen, header of ISTS.
- Dr. Csaba Pinter, MSc, Queen's University.
- Dr. Andras Lasso, Ph.D., Queen's University.
Contents
Module Description
This module calculates geodesic path in 3D structure. Thanks to this geodesic path, this module could draw an EEG 10-20 system.
Terminology
- Mesh A mesh or polygon mesh is a collection of vertices, edges and faces that defines the shape of a polyhedral object in 3D computer graphics and solid modeling.
- Shortest path In graph theory, the shortest path problem is the problem of finding a path between two vertices (or nodes) in a graph such that the sum of the weights of its constituent edges is minimized.
- 10-20 EEG system The International 10-20 system is commonly used for electroencephalogram (EEG) electrode placement and for correlating external skull locations to underlying cortical areas.[1]
Use Cases
The overall goal is to allow users to find the shortest paths between nodes in a graph and via the Dijkstra's algorithm to make 10-20 system. This module can be used for:
- Stimulation in psychiatry
- Surgery measurement
- 3D printing
Panels and their use
Create a mesh
A typical straightforward Geodesic Slicer workflow for consists of the following steps:
- Load a volume.nii.
- Enter in the Geodesic Slicer module using either the toolbar or the Modules menu button.
- Press the button "Create a mesh".
- Wait a moment.
- If the segmentation is fine, press the button "Use this mesh".
- If your image was named 't1.nii' the output will be called 't1.stl', in the same directory of your initial image.
- Go to Parameters to find the shortest path or Make 10-20 EEG system electrode section.
Parameters to find the shortest path
- Source points: The list of fiducial points on the curve, since the "Create-and-place Fiducial" button (in green in the figure above).
- Input STL model: The model you use (after "use this mesh", the t1.stl created).
- Find the shortest path: Calculate in centimeter the geodesic (shortest) path via the Dijkstra's algorithm.
- Draw the shortest path: Draw the Dijkstra's algorithm shortest path.
- Length (cm): The length of the current curve is shown in centimeter.
10-20 system electrode
Run the Dijkstra's algorithm to make the 10-20 system electrode distances.
4 anatomical landmarks
- Source points: The list of fiducial points on the curve, since the "Create-and-place Fiducial" button (in green in the figure above). Four anatomical landmarks are used for the essential positioning of the electrodes (in this order!):
- 1/the nasion
- 2/the inion
- 3/the pre auricular to the left ear
- 4/the pre auricular to the right ear
- Input STL model: The model you use (after "use this mesh", the t1.stl created).
- Press the button "Make 10-20 EEG system electrode" to draw the 10-20 EEG system via the Dijkstra's algorithm.
- Distance T3-Stim in the T3P3 axis are give in centimeters. "Stim" was defined as the stimulation target defined in this article [4].
Information for Developers
The code is available at Github.
References
- ↑ Jasper, H.H. The ten-twenty electrode system of the International Federation. Electroencephalogr. Clin. Neurophysiol., 1958, 10: 370-375
- ↑ Hoffman RE. et al., Transcranial magnetic stimulation of Wernicke’s and Right homologous sites to curtail “voices”: a randomized trial. Biol Psychiatry 2013;73:1008–14
- ↑ Dollfus S. et al., Efficacy of high‐frequency neuronavigated rTMS in auditory verbal hallucinations: a double‐blind controlled study in patients with schizophrenia. Schizophr Bull 2017. In press
- ↑ Briend F. et al., Is T3P3 is the best target to treat patients suffering from schizophrenia with auditory hallucinations?. Brain Stimulation, submitted
