[Reference] apply a Warp Field to a tractogram

Hello to all the MRtrix community!

As we know, one of the common practices for orienting the streamlines of a tractogram from a “moving” to a “fixed” space is to apply a Warp Field (and/or an Affine Transformation).
A common way of deriving the Warp Field is by means of the registration of 3D volumes (usually T1-w or FA Map) for example using ANTs or FSL.

In a previous post a practical and detailed guide was also reported (thanks maxpietsch): Registration: using transformations generated from other packages

I wanted to ask if there is a main source (a paper) of this method / practice i.e. to warp tractograms using transformations derived from the registration of 3D volumes.

Thank you so much,

Gabriele

Welcome Gabriele!

I recall having encountered the same issue myself a number of years back, not quite knowing what / who to cite. It was specifically this work, which does at least show in a figure that it’s the streamlines data themselves that are transformed. But I certainly wasn’t the first one to do so; in fact even MRtrix 0.2 had a command for doing this IIRC. I’ve got a feeling that after the submission of that abstract and having chatted with a couple of people, we decided that the first demonstrated use we knew of was the Average Pathlength Map (APM) article by @Kerstin. But if anyone knows of anything earlier, please do correct me.

Cheers
Rob