• Introducing

    Limbus Contour

    Automatic Contouring for Radiation Therapy

    Clinical grade contours backed by comprehensive research.

    Install on your existing computers. Patient data stays local and secure.

    Request Demo arrow_forward_ios See Contours
  • Clinically validated deep learning segmentation for radiotherapy


    Scans are contoured in seconds using preferred structure set templates from planning.


    Contours generated automatically and sent immediately to treatment planning system after each scan. Configure once, implement in workflow forever.


    Extensive library of clinically validated anatomical structures ready for immediate use out of the box.


    State of the art deep learning entirely on local computers. No cloud transfer of patient data required.

  • Limbus Contour

Full Automation

CT images processed immediately after each scan. Limbus Contour detects and applies the correct clinical template, and sends the contours to the treatment planning system for manual review.

Limbus Contour Software Automation
  • 3D Head Neck Segmentation
  • Easy to Setup

    AI contours up and running in minutes with your existing treatment planning system.

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      Setup in Minutes

      Get automatic contouring up and running in less than an hour. Create Templates and customize contour metadata to match your treatment protocols. Configure Limbus Contour to detect the correct treatment site and apply the appropriate Template for planning.

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      Vendor Neutral

      Contours exported as compliant DICOM RT-Structure files. Supports a wide variety of treatment planning systems. No plug-ins or extensions needed.

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      Supported Platforms

      Supports Windows (7 and above) and MacOS (10.14+). No GPU required. One click install on an existing workstation. No cloud, no patient data privacy concerns.

Expert Grade Contours

Select Scan view_list

5 - 10x faster than manual contouring

Organs at Risk

Limbus Contour features a large selection of organ contours (OARs) that work right out of the box immediately. No atlas creation or local curation of data necessary. All typical organs at risk and CTV structures included.

  • CNS





    Lacrimal Glands


    Optic Nerves

    Spinal Cord



    Temporal Lobes


  • Head and Neck



    Brachial Plexus


    CTV Neck



    Lacrimal Glands




    Optic Nerves

    Oral Cavity

    Parotid Glands

    Spinal Cord

    Submandibular Glands



    Pharyngeal Constrictors

  • Lung and Breast


    CTV Axillary LN


    Brachial Plexus






    Proximal Bronchial Tree

    Spinal Cord



    Bowel Loops

    Breast Structure


  • Pelvis


    Femoral Heads

    Pelvis LN

    Penile Bulb



    Seminal Vesicles

    Bowel Bag

    IIiac Crest


Available - Coming Soon

Clinical Target Volumes

Clinically validated CTVs to speed up the treatment planning process. Elective nodal CTVs across a variety of treatment sites. Configure Limbus Contour to export only every 2nd, 3rd, or nth slice to speed up manual adjustments and review.

  • Head / Neck
  • Breast
  • Pelvis
    • Head and Neck

      Elective Neck Lymph Node CTV

      Includes level IB, II, III, IV, V, VIIa/b. Provides an effective starting point for manual editing and review.

    • CTV Breast
    • Breast

      Breast Axillary CTV

      Axillary levels I, II, III and supraclavicular lymph node regions.

      Internal Mammary Lymph Node CTV (IMC)

      Internal mammary lymph node region spanning the first three intercoastal spaces.

    • CTV Breast
    • Pelvis

      Elective Pelvis Lymph Node CTV

      Pelvis lymph node region spanning lymph nodes including obturator lymph nodes, internal and external iliac lymph nodes (cropped anteriorly at level of femoral heads) up to common iliac lymph nodes (L5/S1 region).

      Prostate and Seminal Vesicle

      Prostate and seminal vesicle to speed up manual prostate CTV contouring.

    • CTV Breast

    Continuously Improving

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    Expert Datasets

    Segmentation models are trained on large datasets which have been meticulously reviewed by experts and standardized to meet contouring guidelines.

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    Clinically Driven

    External testing and continuous prospective clinical evaluation ensures each organ model is reliable.

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    Better with Time

    AI contours undergo routine clinical evaluation and re-training to fine tune and improve models over time. New structures are added regularly.

What our users are saying

Thousands of treatments have been planned using Limbus Contour - Here’s what clinicians have to say:

  • "We aim to deliver radiotherapy treatments in the shortest timeframe possible. At the same time, radiotherapy is evolving rapidly with Adaptive treatment, Hypofractionation and SABR which require very accurate structure definition and thus thinner slices. This increases the required time for contouring, placing more pressure on staffing resources and workflow. AI based algorithms offer great potential to reduce this pressure.

    From our initial investigation, Limbus Contours is providing excellent results for multiple sites. For example, within minutes we can create the main contours required for a prostate treatment. After reviewing numerous cases we have found that the contours produced required very minimal editing. This allows us to very significantly decrease the amount of time required before starting the planning stage.

    The software is very easy to setup and straightforward to use. We have also found the Limbus team extremely responsive to our requests with an excellent support, even though we are very far away and in a completely different time zone."

    personJerome Gastaldo - Chief Physicist

  • "Limbus Contour is saving me at least 45 -60 minutes for pelvis patients, about 45-60 minutes for SRT Brain patients, about 30 minutes for Lt Breast 4-field patients, about 20 minutes for thorax patients, and at least 30 minutes for Head and Neck patients. As you can see, Limbus Contour makes a big difference on our workload, especially when we are busy."

    personRainbow Yu - Radiation Therapist

  • "I have really appreciated the time saved using Limbus both in CT and in Dosimetry. Most useful from my perspective has been the head and neck contouring. I always found the parotids and submanibular glands very hard to delineate. But now with Limbus Contour it helps focus your attention and lets you follow the structure better and usually only small changes need to be made. From a pure work standpoint, the femoral heads are so tedious to contour and having them done is fantastic. The more structures Limbus Contour can do the more time we can focus on doing the dosimetry. I would suggest that for head and neck it has saved me 80% of the time it used to take."

    personJim Runkel - Dosimetrist

  • "As a center we have really loved using Limbus and have become heavily dependent on it. It has been a great technology that we really value that allows us to spend more time scanning patients and lets us still complete contouring efficiently and expertly."

    personManpreet Sohi - Resource Radiation Therapist


Performance backed by leading research. Limbus AI is committed to proving the value of AI in medicine through published peer reviewed research.

Radiotherapy & Oncology (Green Journal)

March 01, 2020

Comparing deep learning-based auto-segmentation of organs at risk and clinical target volumes to expert inter-observer variability in radiotherapy planning

View Publicationlibrary_books

Practical Radiation Oncology

June 27, 2020

Clinical evaluation of deep learning and atlas based auto-contouring of bladder and rectum for prostate radiotherapy

View Publicationlibrary_books

ASTRO 2020 and CARO 2020

  • Implementation of Deep Learning-Based Auto-Segmentation for Radiotherapy Planning Structures: A Multi-Center Workflow Study

    Recipient of CARO 2020 Award for Best Abstract in Science and Applied Technology

    View Abstractlibrary_books
  • Applications of Deep Learning for Automatic Contouring of Tumors in the Brain

    Recipient of CARO 2020 Award for Abstracts Submitted by the Medical Student Research and Mentorship Awardees

  • Deep Learning-based Auto-Segmentation for Pelvic Organs at Risk and Clinical Target Volumes in Intracavitary High Dose Rate Brachytherapy

    View Abstractlibrary_books

ASTRO 2019

  • Comparing Deep Learning-based Auto-segmentation of Organs at Risk and Clinical Target Volumes to Expert Inter-Observer Variability in Radiotherapy Planning

    View Abstractlibrary_books
  • Validation of Deep Learning-based Auto-Segmentation for Organs at Risk and Gross Tumor Volumes in Lung Stereotactic Body Radiotherapy

    View Abstractlibrary_books
  • Automatic Deep Learning-based Segmentation of Brain Metastasis on MPRAGE MR Images for Stereotactic Radiotherapy Planning

    View Abstractlibrary_books

Copyright 2020 Limbus AI Inc.