DICOM viewer modified version of the project by Wen-Ya Lin :
original project
Launch the DICOM viewer node in the nitd.launch.py file.
Select 3D processing, select load DICOM file and open the folder containing the dicom slices, click on set insertion point and set target point buttons to set the trajectory, this will be displayed in RViz as a red line.
For more information about the coordinates transformations and workings of the DICOM viewer, check L. MALDONADO Report