Multi contrast, 2D and 3D

The available segmentation networks

Aiming to cover the full body

With our framework we are able to automatically detect the body location. For each body part dedicated small light weight networks are developed and trained. If the data contains multiple locations the data is cut in various regions with considerable overlap and each is segmented by the correct neural network after which everything is collected in one segmentation file.

Body locations for which muscle segmentation UNETs are developed.

We aim to have segmentation networks for both GE and TSE Dixon based imaging that work on the raw magnitude data, in and out phase images and the reconstructed water and fat maps. Segmentation works best on 3D continuous datasets however those are not always available. Therefore we train our networks in 2D and 3D (except for the arm, see below). If data is acquired in 2D with slice gaps or extremely thick slices the 2D networks can be used. However 3D continuous data with 3D segmentation networks outperform the 2D variants consistently.

Body locations for which muscle segmentation UNETs are done.

Networks included in QMRITools

Before segmentation, one classification network (Body_Pos_Side) determines the body location and side of the data. The following region networks are included.

Region 2D network 3D network Label file
Shoulder yes yes N2_Shoulder
Hip yes yes N4_Hip
Upper leg yes yes N5_UpperLeg
Lower leg yes yes N6_LowerLeg
Arm no yes N7_Arm
Torso not yet available not yet available N3_Torso
Head and neck not yet available not yet available N1_HeadNeck

The output of the networks is converted to standardized muscle labels. The full body label set (S1) is used by default, and older label sets for the legs and hip (S2), shoulder (S3) and upper arm (S4) are available. How to use the networks is described here, and how to train your own networks here.

We gratefully acknowledge the support of NVIDIA with the donation of GPU used for this work.