Creation of ROI aligned with freehand ultrasound sweeps -- how to rotate the ROI?

Hi,

I think my question is quite a beginner question, but since a year now I am doing freehand 3D ultrasound and I just realised that the ROI I am using has a lot of impact on my volume reconstruction.
I am therefore trying to adjust the ROI the more possible to the axis of my sweeps.
However I cannot find how to rotate the ROI ? I tried applying a transform to the ROI, but then the volume reconstruction did not work anymore …

Thanks in advance for your help,
Cheers,
Aurélie

Currently in the Volume Reconstructor module in Slicer you cannot specify axis directions. I’ve submitted an issue to make sure it gets implemented:

Would you like to give it a try and implement it. We can help you getting started, but it requires basic C++ programming skills.

Alternatively, you can rotate your entire reference coordinate system by applying adding a custom transformation. For example, you can add ReferenceToRotatedReference) and send all transforms and images in RotatedReference instead of Reference.

Thank you for your quick answer.
I apologize but I do not think I have the skills to implement this in Slicer …

As you offered, I applied a custom transformation to my full trial and the volume reconstruction worked well !
However, my ROI and the axis of my sweeps change for each acquisition I do, since I am sweeping different muscles of different sizes in different body positions … . so it would be a lot easier for me if it was possible to directly adjust the ROI size and orientation.

How can I be kept updated if that becomes possible someday?
Thanks again,
Cheers,
Aurélie

Watch the issue referenced above. I think you can set automatic email notification when the state of the issue changes.