TotalSegmentator MR

Version 2.18.0 · Licence Apache-2.0 · Released 2026-08-23

MRI

TotalSegmentator MR segments anatomical structures in MRI scans, with whole-body, body-outline, spine, and liver task options.

Available tasks (5)

Task options define what the model does. Choose one when you submit a scan or configure generation.

Input: MRI scan.
Output: Segmentation label map (.nii.gz).

Total — full body (MR, 50)

Default

Default MRI task: 50 anatomical structures.

View 50 output classes

1 spleen2 kidney_right3 kidney_left4 gallbladder5 liver6 stomach7 pancreas8 adrenal_gland_right9 adrenal_gland_left10 lung_left11 lung_right12 esophagus13 small_bowel14 duodenum15 colon16 urinary_bladder17 prostate18 sacrum19 vertebrae20 intervertebral_discs21 spinal_cord22 heart23 aorta24 inferior_vena_cava25 portal_vein_and_splenic_vein26 iliac_artery_left27 iliac_artery_right28 iliac_vena_left29 iliac_vena_right30 humerus_left31 humerus_right32 scapula_left33 scapula_right34 clavicula_left35 clavicula_right36 femur_left37 femur_right38 hip_left39 hip_right40 gluteus_maximus_left41 gluteus_maximus_right42 gluteus_medius_left43 gluteus_medius_right44 gluteus_minimus_left45 gluteus_minimus_right46 autochthon_left47 autochthon_right48 iliopsoas_left49 iliopsoas_right50 brain

Body outline (MR)

Body outline and extremity segmentation for MRI.

View 2 output classes

1 body_trunc2 body_extremities

Vertebrae (MR)

Individual vertebra segmentation for MRI images.

View 25 output classes

1 sacrum2 vertebrae_L53 vertebrae_L44 vertebrae_L35 vertebrae_L26 vertebrae_L17 vertebrae_T128 vertebrae_T119 vertebrae_T1010 vertebrae_T911 vertebrae_T812 vertebrae_T713 vertebrae_T614 vertebrae_T515 vertebrae_T416 vertebrae_T317 vertebrae_T218 vertebrae_T119 vertebrae_C720 vertebrae_C621 vertebrae_C522 vertebrae_C423 vertebrae_C324 vertebrae_C225 vertebrae_C1

Liver segments (MR)

Couinaud liver segment classification for MRI.

View 8 output classes

1 liver_segment_12 liver_segment_23 liver_segment_34 liver_segment_45 liver_segment_56 liver_segment_67 liver_segment_78 liver_segment_8

Liver lesions (MR)

Hepatic lesion segmentation for MRI.

View 1 output class

1 liver_lesions

Research details

Training data

Trained on a multi-sequence MRI dataset (TotalSegmentator MR extension, Akinci D'Antonioli et al. 2024) covering common abdominal/pelvic and whole-body sequences; expert-reviewed annotations. Adult human anatomy.

Intended use

Research segmentation of major organs and structures in MRI. Best on the sequence types represented in training; intended for cohort/morphometric analysis and as a correction starting point, not diagnosis.

Known limitations

MRI intensity is not standardised across scanners/sequences, so performance varies more than CT. Degrades on sequences/contrasts outside the training distribution, heavy motion or susceptibility artefact, and non-standard fields of view.

Species

human

Citations & references

Citing Nalvera.AI

Please cite the platform alongside the model's own paper listed above — the model authors deserve the credit for the method.

@misc{nalvera,
  title        = {Nalvera.AI: a cloud platform for medical-imaging AI},
  author       = {{van der Heyden, Brent}},
  year         = {2026},
  howpublished = {\url{https://nalvera.ai}},
  note         = {Model: TotalSegmentator MR v2.18.0. Accessed YYYY-MM-DD}
}

Research use only — not a medical device. Outputs are not validated for clinical diagnosis or treatment.

Run this model → ← Back to models