/MRSegmentator

Primary LanguagePythonApache License 2.0Apache-2.0

MRSegmentator: Robust Multi-Modality Segmentation of 40 Classes in MRI and CT Sequences


Continuous Integration License: Apache PyPI Code style: black

Detect and segment 40 classes in MRI scans of the abdominal / pelvic / thorax region

Contrary to CT scans, where tools for automatic multi-structure segmentation are quite mature, segmentation tasks in MRI scans are often either focused on the brain region or on a subset of few organs in other body regions. MRSegmentator aims to extend this and accurately segment 40 organs and structures in human MRI scans of the abdominal, pelvic and thorax regions. The segmentation works well on different sequence types, including T1- and T2-weighted, Dixon sequences and even CT images. Read more about it in our preprint: https://arxiv.org/pdf/2405.06463.

Check out some sample segmentations on our Hugging Face Space! 🤗

Update:

MRSegmentator v1.0.0 did occasionally mix left & right classes. I retrained the model using the nnUNetTrainerNoMirroring trainer. The new version is vastly better in this regard. The updated weights will be automatically downloaded with the latest pip release. You can update with:

python -m pip install --upgrade mrsegmentator==1.1

(Make sure to include the version number, sometimes pip doesn't do what you'd expect it to do.)

Sample Image

Installation

Install MRSegmentator with pip:

# Create virtual environment
conda create -n mrseg python=3.11 pip
conda activate mrseg

# Install MRSegmentator
python -m pip install mrsegmentator

(Optionally) If the installed pytorch version coming with nnunet is not compatible to your system, you might need to install it manually, please refer to PyTorch.

Inference

MRSegmentator segments all .nii and .nii.gz files in an input directory and writes segmentations to the specified output directory. MRSegmentator requires a lot of memory and can run into OutOfMemory exceptions when used on very large images (e.g. some CT scans). You can reduce memory usage by setting --split_level to 1 or 2. Be aware that this increases runtime and possibly reduces segmentation performance.

mrsegmentator --input <nifti file or directory>

Options:

-i, --input <str> [required] # input directory or file

--outdir <str>  # output directory
--fold <int> # use only a single model for inference 
--postfix <str> # postfix that will be added to segmentations, default: "seg"
--split_level <int> # split images to reduce memory usage. Images are split recusively: A split level of x will produce 2^x smaller images.

--batchsize <int> # how many images can be loaded to memory at the same time, default: 8
--nproc <int> # number of processes
--nproc_export <int> # number of processes for exporting the segmentations
--cpu_only # don't use a gpu
--verbose

Python API

from mrsegmentator import inference
import os

outdir = "outputdir"
images = [f.path for f in os.scandir("image_dir")]
folds = [0]

inference.infer(images, outdir, folds)

How To Cite

If you use our work in your research, please cite our preprint on arXiv: https://arxiv.org/pdf/2405.06463.

Hartmut Häntze, Lina Xu, Felix J. Dorfner, Leonhard Donle, Daniel Truhn, Hugo Aerts, Mathias Prokop, Bram
van Ginneken, Alessa Hering, Lisa C. Adams, and Keno K. Bressem. MRSegmentator: Robust multi-modality
segmentation of 40 classes in MRI and CT sequences. arXiv, 2024.

Class details

Index Class
0 background
1 spleen
2 right_kidney
3 left_kidney
4 gallbladder
5 liver
6 stomach
7 pancreas
8 right_adrenal_gland
9 left_adrenal_gland
10 left_lung
11 right_lung
12 heart
13 aorta
14 inferior_vena_cava
15 portal_vein_and_splenic_vein
16 left_iliac_artery
17 right_iliac_artery
18 left_iliac_vena
19 right_iliac_vena
20 esophagus
21 small_bowel
22 duodenum
23 colon
24 urinary_bladder
25 spine
26 sacrum
27 left_hip
28 right_hip
29 left_femur
30 right_femur
31 left_autochthonous_muscle
32 right_autochthonous_muscle
33 left_iliopsoas_muscle
34 right_iliopsoas_muscle
35 left_gluteus_maximus
36 right_gluteus_maximus
37 left_gluteus_medius
38 right_gluteus_medius
39 left_gluteus_minimus
40 right_gluteus_minimus