Introduction

Background

SNOMED CT terminology provides a common language that enables a consistent way of indexing, storing, retrieving, and aggregating clinical data across specialties and sites of care.

SNOMED International maintains the SNOMED CT technical design, the content architecture, the SNOMED CT content (includes the concepts table, the descriptions table, the relationships table, a history table, and ICD mappings), and related technical documentation.

Purpose

This document provides a summarized description of the content changes included in the July 2024 release of SNOMED Clinical Terms^® (SCT) International Edition.

It also includes notes detailing the known content or technical issues where the root cause is understood, the fix has been discussed and agreed to, but has yet to be implemented.

The SNOMED International release notes are available alongside the July 2024 International Edition.

Scope

This document is written for the purpose described above and is not intended to provide details of the technical specifications for SNOMED CT or encompass every change made.

Audience

The audience includes National Release Centers, WHO-FIC release centers, vendors of electronic health records, terminology developers and managers who wish to have an understanding of changes that have been incorporated into the July 2024 International Edition.

Please note, you may have to register for a Confluence user account in order to access the links included in these release notes.

Important Information

Content Development Activity

Summary

Continuous quality improvement and enhancement of existing content is an ongoing process undertaken by SNOMED International in preparation for every release. The July 2024 International Edition has seen a continuation of the work driven by contributions from: Kaiser Permanente i.e. Convergent Medical Terminology (CMT), Global Medical Device Nomenclature Agency (GMDNA), Orphanet and other domain specific collaborations as well as requests received via the Content Request System (CRS). 

Information about editorial decisions may be found in the SNOMED CT Editorial Guide; mapping guidance for ICD-10 can be found here.

Quality Initiative

The Quality Initiative (QI) project is the implementation of the Quality Strategy. After a successful pilot project for the July 2018 Edition release, the next stage has been implemented for subsequent releases including July 2024. 

Quality improvement tasks are being deployed to improve internal structural consistency and ensure compliance with editorial policy related to the stated modeling of content. Additionally, correction or addition of defining relationships is being carried out to accurately reflect current clinical knowledge and ensure the semantic reliability of descriptions associated with a concept. 

Update Head and Neck

18 concepts were identified with FSN of “head and neck” but modeled with 774007 |Structure of head and/or neck (body structure)|. For some concepts the intention had always been disjunctive “and/or” so to minimise disruption the FSN’s have been changed to reflect this intended meaning with therefore no change in descendants.

Procedures such as 430215009 |Biopsy of head and neck structure (procedure)| have been inactivated and replaced with distinct concepts for each body site as a disjunctive in this instance would be a grouper of no clinical significance and non-conformance to editorial policy. This impacted the descendants who have become children of the distinct concepts.

Examples of concepts inactivated and replaced with two distinct concepts:

• 430215009 |Biopsy of head and neck structure (procedure)| 
• 431056007 |Fine needle aspiration biopsy of head and neck structure (procedure)| 
• 430220009 |Specimen from head and neck structure (specimen)|

Examples of concepts with model change to two role groups (finding/disorder can occur in both structures at the same time):

• 255057000 |Benign tumor of head and neck (disorder)| 
• 716659002 |Squamous cell carcinoma of head and neck (disorder)|
• 274755005 |Head and neck swelling (finding)|

Examples of concepts with FSN change to 'and/or':

• 301871007|Lipoma of head and neck (disorder)|
• 441535001|Adenocarcinoma of head and neck (disorder)|
• 1197313009|Metastatic adenocarcinoma to lymph node of head and neck (disorder)|

Number of concepts edited (approx): 18

 Update Effect of Radiation

1335858009 |Effect of radiation (finding)| and subtypes have been reviewed to apply consistency to descriptions and model. Radiation is a physical force and thus uses the 'caused by' for descriptions.

The causative agent for this set of concepts has been checked for appropriateness as only ionizing radiation can cause damage to internal structures, i.e. beyond skin and/or eyes. Conditions caused by radiotherapy were also included in this review, and standardized descriptions have been applied.

Number of concepts edited (approx): 350

Update Construction of Stoma

75506009|Construction of stoma (procedure)| and subtypes have been reviewed and a consistent approach to modeling has been implemented.

A small number of concept inactivations and description changes have been implemented as part of this review.

Number of concepts edited (approx): 100

Update Glomus Tumor

403969002|Glomus tumor (disorder)| has been inactivated and replaced with new concept 1340052006 |Benign glomus tumor (disorder).

10438002 |Glomus tumor (morphologic abnormality)| has been inactivated with reason ambiguous and replaced with 1340048006 |Benign glomus tumor (morphologic abnormality)|.

Similar 6 disorder concepts referring to 'glomus tumor' have been inactivated and replaced with 'benign glomus tumor'.

4 procedure concepts have been inactivated and replaced with procedure concepts that specify 'benign'.

Concepts in the morphology hierarchy have been aligned with ICD-O-3.2 and are informed by the WHO Blue Books.

Update Aneurysm

Intracranial aneurysms and related concepts have been remodeled with 281138005 |Intracranial vascular structure (body structure)| to include conditions or procedures that involve either arteries or veins.

75087007 |Repair of aneurysm (procedure)| Addressed missing subconcepts of repair of aneurysms by GCI axioms to infer subconcepts that are achieved by specified methods, such as embolization, ligation, excision, and coagulation.

Number of concepts edited (approx): 36

 Body Structure 

Update Posterior Abdominal Wall

22577007 |Posterior abdominal wall structure (body structure)| has been remodelled as a subtype of 822992007 |Structure of wall of abdominal proper segment of trunk (body structure)| to improve accuracy for this area of content.

Number of concepts edited (approx): 10

SEP and Laterality Anatomy Reference Sets

The release file for the lateralizable body structure reference set has been updated and validated.

The release file for the SEP reference set has been updated and validated.

Clinical Finding

Update Eosinophilic Gastritis

66329006 |Eosinophilic gastritis (disorder)| and subtypes have been remodeled as allergic conditions based on recent findings that these conditions are generally accepted as a Th2-mediated allergic reactions.

Procedure

Radiographic Imaging

Work is progressing for this content tracker.  42687005|Lymphangiogram (procedure)| and subtypes have been reviewed as part of the tracker.

Based on user feedback and review, ‘lymphangiography’ uses fluoroscopy and contrast unless an alternative imaging method such as MRI is specified. The content in this hierarchy that currently states ‘lymphangiography’ with method 278110001|Radiographic imaging - action (qualifier value)| has been inactivated and replaced with a new concept which specifies the imaging modality and the use of contrast.

For example: 48858003 |Lymphangiography of lower extremity (procedure)| has been inactivated and replaced by a new concept: Fluoroscopic lymphangiography of lower limb with contrast (procedure)|

A new supertype concept has been added: 1336147007 |Imaging of lymphatic system (procedure)|

Work for this content tracker continues, for information please see the informational briefing note here.

Qualifier Value

Revision of Definition of Temporal Period

Following user feedback, the definition of 1260427008 |Maternal antepartum and/or intrapartum and/or postpartum period (qualifier value)| has been updated. A set of concepts relating to 'perinatal findings' have been inactivated as erroneous with historical association to nine new disorder concepts relating to jaundice in the early neonate.

Update 284009009 |Route of administration value (qualifier value)|

The route of administration is the path by which the product is taken into or makes contact with the body, and is a property of the administration action. The route of administration of a medication is determined by the prescriber in their prescription dosage instructions for a particular patient.

284009009 |Route of administration value (qualifier value)| and subtypes have definitions that have existed for many years and in 9 cases these conflated the site of effect/action and the route of administration or gave other extraneous information. These definitions have been amended or inactivated in the case of 428191002 |Percutaneous route (qualifier value)| which has also been remodeled to 284009009 |Route of administration value (qualifier value)| parent (from topical route).

Inactivation of 362939006 |Dissolution - action (qualifier value)|

362939006 |Dissolution - action (qualifier value)| has been inactivated.

Substance

Update 312301006 |Infective organism antibody (substance)|

The descriptions for the descendants of 312301006 |Infective organism antibody (substance)| (antibody to X or X antibody) have been updated as per editorial guidelines where applicable.

Social Context

Inactivation of 60134006 |Life style (life style)| and Subtypes

60134006 |Life style (life style)| and subtypes has been inactivated as these concept refer to findings about behaviors that an individual has engaged in and not lifestyle. 134436002|Lifestyle (finding) | has also been inactivated.

Model Component Metadata

Dose Form Intended Site and Route of Administration

While there has been no change to the dose form model, and based on a request for clarification, following discussion at the Drug Extension User Group new definitions have been added to the following concepts:

• 736474004 |Has dose form intended site (attribute)|
  Dose form intended site describes the general anatomic location that the dose form has been formulated for administration to or at. The intended site is not intended to describe a precise site or route of administration. For example, eye drops (prepared for ocular intended site) are subject to pharmacopoeial standards for pH, and sterility.
• 410675002 |Route of administration (attribute)|
  The route of administration is the path by which the product is taken into or makes contact with the body, and is a property of the administration action. The route of administration of a medication is determined by the prescriber in their prescription dosage instructions for a particular patient.
• 736479009 |Dose form intended site (intended site)|
  The set of values for dose form intended site that relate to characteristics associated with a pharmaceutical dose form and do not refer to a precise anatomic location.
• 284009009 |Route of administration value (qualifier value)|
  The set of values for route of administration. For medicinal products these values are associated with the action of administration

Collaboration/Harmonization Agreements

Convergent Medical Terminology (CMT)

185 new concepts have been added. The focus area was musculoskeletal with smaller additions to other domains such as neoplasms and injuries.

Orphanet

Working in collaboration with Orphanet (http://www.orpha.net/consor/cgi-bin/index.php), efforts are ongoing to update rare disease concepts in SNOMED CT to maintain alignment with Orphanet for the annual update of the SNOMED CT to Orphanet Maps.

All of the concepts added for the Orphanet project have been mapped to ICD-10.

Cancer Synoptic Reporting

Cancer synoptic reports are used by many member countries to record pathology examination of cancer specimens including the College of American Pathologists (US and Canada), Royal College of Pathology (UK), Royal College of Pathology Australasia (Australia, New Zealand), PALGA (The Netherlands), Swedish Society of Pathology, and others.

For more information about this project, please see Cancer Synoptic Reporting Clinical Project Group 

International League Against Epilepsy (ILAE)

In line with approved harmonized terminology, this project is working on alignment including restructuring to update the hierarchy  << 313307000 |Epileptic seizure (finding)|.

Further information about the project is available here

Gravity Project

Work for this project is ongoing.

Internal Quality Improvement

Machine Readable Concept Model (MRCM) Changes

There are no changes for the MRCM in the June 2024 International Edition.

Future changes that are currently in progress can be viewed via the MRCM Daily Build Browser

Please see early visibility for future planned changes to MRCM.

OWL Axiom Expressions for Annotation Properties

The new annotation properties are represented in the OWL expression axiom refset as follows:

• The 1295447006 |Annotation attribute (attribute)| is correctly represented as subClassOf

  • 01300ccd-d1d7-417d-a70a-f688e72c4d8c 20231201 1 900000000000012004 733073007 1295447006 SubClassOf(:1295447006 :246061005)

• All subconcepts of 1295447006 |Annotation attribute (attribute)| are represented as "SubAnnotationPropertyOf", instead of "subClassOf" as they previously were

  • e6cd65fe-cb81-4db4-9ac4-040dc74fce28 20231201 1 900000000000012004 733073007 1295448001 SubClassOf(:1295448001 :1295447006)

  • 3729ce47-a96e-4dc7-9eff-83c34740c414 20231201 1 900000000000012004 733073007 1295449009 SubClassOf(:1295449009 :1295447006)

These axiom updates are published in the March 2024 International Edition release. The authoring tool has been updated to ensure all new subconcepts of 1295447006 |Annotation attribute (attribute)| are represented as SubAnnotationPropertyOf(). The remaining changes required for other tools to correctly consume the updated syntax have been completed for the June 2024 International Edition release.

SNOMED CT derived products

ICD-10 map

The SNOMED CT to the International Statistical Classification of Diseases and Related Health Problems, Tenth Revision (© World Health Organization 1994) 2016 Version map (SNOMED CT to ICD-10 Map) is included in the SNOMED CT International Edition as a Baseline. The SNOMED CT to ICD-10 Map was created to support the epidemiological, statistical and administrative reporting needs of SNOMED International member countries and WHO Collaborating Centers.

The SNOMED CT to ICD-10 Map is released in Release Format 2 (RF2) only. It is located in the file der2_iisssccRefset_ExtendedMapFull_INT_20200731.txt, which is in the Map folder under Refset, in each of the three RF2 Release Type folders. 

The SNOMED CT to ICD-10 Map is released as Refset 447562003 |SNOMED CT to ICD-10 extended map (foundation metadata concept).

The ICD-10 Mapping Technical Guide (including exemplars) is hosted here https://confluence.ihtsdotools.org/display/DOCICD10

Content Development Activity Summary

The map is a directed set of relationships from SNOMED CT source concepts to ICD-10 target classification codes.  The SNOMED CT source domains for the MAP are limited to subtypes of 404684003 |clinical finding|, 272379006 |event| and 243796009 |situation with explicit context|.  The target classification codes are ICD-10 2016 release. 

Mapped content for July 2024

The map provided for the July 2024 International Edition has been updated, and now represents a complete map from SNOMED CT International Edition to ICD-10 2016 version.

• 376 newly authored concepts have been added and mapped.

• The SNOMED to ICD-O (morphology) map has 4 additional concepts added as a result of the ICD-O 3.2 review or added due to CRS requests. 

We would welcome feedback on any issues that users of the map may detect when using the map. Issues should be submitted via mapping@snomed.org

SNOMED CT to OWL conversion and classification

The repository containing the toolkit enabling simple SNOMED CT to OWL conversion and classification can be found here, including documentation on its use: https://github.com/IHTSDO/snomed-owl-toolkit

Please contact SNOMED International at support@snomed.org if you would like to provide any feedback on ways to extend and improve the new toolkit.

Technical notes

Known Issues

Known Issues are content or technical issues where the root cause is understood, and the resolution has been discussed and agreed but has yet to be implemented.  This can be due to a number of reasons, from lack of time within the new monthly editing cycles, to the risk of impact to the stability of SNOMED CT if the fix were to be deployed at that stage in the Product lifecycle.  

For the current SNOMED CT International edition, the following Known Issues were identified, and agreed to be resolved in future editing cycles:

Resolved Issues

Resolved issues are Known Issues which were not fixed as part of the previous release lifecycle, but which have now been resolved in the latest release.  They can also be issues found during testing of the current release, which were resolved before the final deployment of the Production release.  Finally they can be issues which were reported or found during the testing phase, but which have been closed without any action taken.  

The Resolved Issues for the current SNOMED CT International edition can be found here:

Technical updates

RF2 package format

The RF2 package convention dictates that all relevant files are included, regardless of whether or not there is content to be included in each release.  Therefore, the package contains a mixture of files which contain both header rows and content data, and files that (intentionally) include only header records.  The reason that these "empty" files are included in the package is to draw a clear distinction between:

1. ...files that have been deprecated (and therefore removed from the package completely), due to the content no longer being relevant to RF2 in future releases 

2. ...files that happen to contain no data in this particular release (and are therefore included in the package with just a header record), but are still relevant to RF2, and could therefore contain content in future releases.

This allows users to easily distinguish between the two scenarios, as otherwise if files in option 2 were left out of the package it could be interpreted as an error, rather than an intentional lack of content in that release.

Changes to the International Edition package format

In line with the new implementation of Annotations, two new refsets have been added to the International Edition Release package, from December 2023 onwards:

• der2_scsRefset_ComponentAnnotationStringValueSnapshot_INT_20240101.txt
• der2_sscsRefset_MemberAnnotationStringValueSnapshot_INT_20240101.txt

These refset files are empty for the June 2024 release, whilst content is authored in future editing cycles.  However, they will then be populated with Annotations data from one of the future 2024 International Edition releases onwards (date to be confirmed).  These improvements were introduced in the December 2023 International Edition release, and will be used in all future International Edition releases until further notice.

Changes to the Annotations Refset format

Changes to the RefsetDescriptor records

Early visibility of impending changes in the upcoming 2024 Monthly International Edition releases

Please see the early visibility Confluence page for details of forthcoming changes.