• Informatics
  • RadLex

  • What is RadLex?

    As images, imaging reports and medical records move online, radiologists need a unified language to organize and retrieve them. Radiologists currently use a variety of terminologies and standards, but no single lexicon serves all of their needs.

    Enter RadLex, a comprehensive lexicon—a unified language of radiology terms—for standardized indexing and retrieval of radiology information resources. With more than 68,000 terms, RadLex satisfies the needs of software developers, system vendors and radiology users by adopting the best features of existing terminology systems while producing new terms to fill critical gaps. RadLex also provides a comprehensive and technology-friendly replacement for the ACR Index for Radiological Diagnoses. It unifies and supplements other lexicons and standards, such as SNOMED-CT and DICOM. RadLex development has received support from both the National Institute of Biomedical Imaging and Bioengineering (NIBIB) and the cancer Biomedical Informatics Grid (caBIG) project.

    RSNA has developed a term browser (radlex.org) to give potential users a convenient way to view RadLex's structure and content. RadLex is available for download via the National Center for Biomedical Computing’s Bioportal.

    In 2005, RSNA formed six RadLex organ system committees. Representatives of more than 30 radiology professional and standards organizations, including the American College of Radiology (ACR), DICOM, and IHE, participated in the process. In November 2006, they publicly released an initial set of more than 7,500 anatomic and pathologic terms. The lexicon has grown over the succeeding years through the continual work of RadLex committees and the addition of terminology drawn from other resources such as the University of Washington's Functional Model of Anatomy.


    RadLex® Playbook is a special component of RadLex that provides a standard system for naming radiology procedures, based on the elements that define an imaging exam such as modality and body part. By providing standard names and codes for radiologic studies, Playbook can facilitate a variety of operational and quality improvements, including workflow optimization, chargemaster management, radiation dose tracking, enterprise integration and image exchange. Click here to learn more about Playbook.

    RadLex and RadLex Playbook are released under an open license that allows for their free use. Click here to review the RadLex license and download RadLex and Playbook.

  • Resources

  • RsnaProgram7

    Bioportal Download

    Download the latest RadLex ontology and review additional details, metrics, versions and projects that use RadLex.


    RadLex License

    This RadLex® License permits use of RadLex® and PlaybookTM without charge.


    Release Notes

    Stay up to date on the latest additions and amendments to RadLex terms, preferred names and synonyms.