ISO/TS 23541-1:2021

TECHNICAL ISO/TS
SPECIFICATION 23541-1
First edition
2021-05
Health informatics — Categorial
structure for representation of 3D
human body position system —
Part 1:
Bones
Informatique de santé — Structure catégorielle pour la
représentation du système de positionnement du corps humain en
3D —
Partie 1: Os
Reference number
©
ISO 2021
© ISO 2021
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ii © ISO 2021 – All rights reserved

Contents Page
Foreword .iv
Introduction .v
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 1
3.1 General . 1
3.2 Characterizing categories . 3
4 Categorial structure of 3D human body position system . 5
4.1 Overview . 5
4.2 Representational relations . 6
4.2.1 shareElement . 6
4.2.2 isBodyPart . 6
4.2.3 hasFinding . 7
4.2.4 hasIntervention . . . 7
4.2.5 hasObservation . 7
4.2.6 hasObject . 8
4.2.7 hasModel . . 8
Bibliography .10
Foreword
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iv © ISO 2021 – All rights reserved

Introduction
Anatomical descriptions can be very abstract, requiring long narrative descriptions. These descriptions
can lead to ambiguity and coding inconsistency. Text-based expressions lack expressiveness and
accuracy, medical information is not captured and re-used sufficiently and there are also issues in
interoperability. There is currently no unified way of expressing anatomical concepts.
However, recent advancements in imaging technology are dramatically revolutionizing the field. For
instance, the spatial resolution in a CT scan is less than 1 mm. Regarding accuracy and expressiveness,
it is believed that the gap between medical imaging and clinical terminology is increasing over time.
Patients are also having problems understanding their disease because visualization is not given by
standard terminology.
Healthcare workers are seeking to achieve additional expressiveness by adopting 3D data in the
medical field. Radiation therapies are designed by 3D systems to generate optimal intensities while
protecting adjacent tissue. In operating theatres, operations are often guided by 3D navigation
systems. For example, arthroplasties are designed and simulated before surgery using 3D technology.
Researchers are also studying ways to simulate operation tactics using 3D data by 3D printing, such
as AR (augmented reality) and VR (virtual reality). Since 3D systems can deliver accurate spatial
information in the human body, it is evident that a standard terminology infrastructure will provide
additional expressiveness, accuracy and comparability when 3D data is adopted in medical informatics.
Since anatomy is a key piece of information in many clinical descriptions, 3D data can increase the
accuracy and expressiveness of clinical terminology. 3D data are numbers that can be processed by
mathematical functions providing more computability in research, software production and artificial
intelligence.
3D systems provide a consistent way of expressing anatomical concepts in a precise manner. Accurate
data can improve data exchange between electronic health records, epidemiological analysis and
quality. Increased accuracy also means better clinical decision support systems for patient safety,
reducing medical errors and improving efficiency. It also provides visual information for patients and
caregivers when conventional standard terminology system does not. HBPS (Human body position
system) is intended to be used in electronic health records, personal health record and various medical
research purposes.
HBPS is a way of expressing clinical concepts by combining 3D data and text-based terminology.
Although the main purpose of 3D is graphical expression, it can play a terminological role in many
ways as it has accurate anatomical concept. It can have attributes that are similar to codes in semantic
terminological system. It can be pre- or post-coordinated, just as conventional terminological concepts.
Since the data inside a 3D system is purely numeric, it can be captured and retrieved better than
semantic medical information.
TECHNICAL SPECIFICATION ISO/TS 23541-1:2021(E)
Health informatics — Categorial structure for
representation of 3D human body position system —
Part 1:
Bones
1 Scope
This document describes the high-level concepts required for representation of 3D data in health
information systems from a terminological perspective. It is intended to be used in analysing,
developing and managing terminologies in HBPS. The use cases include clinical findings, disorders,
problem lists and procedures.
Topics considered in the scope of this document:
— description of terminological concepts for representation of 3D data for human body;
— establishing of the relationships needed for 3D data in terminological systems;
— use cases.
Topics considered outside the scope of this document:
— 3D data structure, implementation and software functionality.
2 Normative references
There are no normative references in this document.
3 Terms and definitions
For the purposes of this document, the following terms and definitions apply.
ISO and IEC maintain terminological databases for use in standardization at the following addresses:
— ISO Online browsing platform: available at https:// www .iso .org/ obp
— IEC Electropedia: available at http:// www .electropedia .org/
3.1 General
3.1.1
3 dimensional
3D
computer graphics that define an object by its width, length and depth
Note 1 to entry: See Figure 1.
Figure 1 — Three-dimensional space and coordinate of a point
3.1.2
3D data element
unit of 3D data for which the definition, identification, representation, and permissible values are
specified by means of a set of attributes
Note 1 to entry: A 3D data element include vertex (a single point that has three-dimensional position and corner
of a 3D model), edge (where two faces meet), face (surface of 3D model defined by vertices and edges) and polygon
(straight-sided shapes, defined by vertices and edges).
Note 2 to entry: See Figure 2.
3.1.3
human anatomy
study of structures in the human body and how the body parts are organized, physical substance of the
human organism
Note 1 to entry: Human anatomy is composed of living cells and extracellular materials and organized into
tissues, organs and systems.
3.1.4
anatomical site
formal representation of a sanctioned characteristic composed of the semantic link {HasAnatomicalSite}
with an associative relation to the characterizing category including but not limited to structure>
[SOURCE: ISO/TS 22789:2010, 3.2.1]
3.1.5
terminology
structured, human and machine-readable representation of concepts
3.1.6
concept
unit of knowledge created by a unique combination of characteristics
[SOURCE: ISO 1087:2019, 3.2.7, modified — Notes to entry removed.]
3.1.7
clinical terminology
terminology describing health conditions and healthcare activities
2 © ISO 2021 – All rights reserved

3.2 Characterizing categories
3.2.1
3D model
three-dimensional model in virtual space composed of 3D data elements (3.1.2)
Note 1 to entry: The 3D model covers the human body model and the 3D site model representing these concepts
virtually.
3.2.2
3D human body model
3D model (3.2.1) that represents a normal anatomical structure
Note 1 to entry: See Figure 2.
Note 2 to entry: A human body model, which defines systems, organs and body regions, is composed of multiple
3D models.
Figure 2 — 3D human body model and 3D data element
3.2.3
3D site model
3D model (3.2.1) that represents anatomical sites (3.1.4)
Note 1 to entry: It is used to annotate clinical concepts, such as disorder, symptom and finding. It describes the
location, size, shape and volume of anatomical areas in which health professionals are interested.
3.2.4
virtual medical entity
entity that represents a medical concept in virtual space
Note 1 to entry: A virtual medical entity is composed of a 3D model and a descriptive entity. The medical
concept (3.1.6) can be pre-coordinated, i.e. predefined within a formal (concept representation) system, with an
equivalent single unique concept identifier, or post-coordinated, i.e. represented using more than one concept
from one or many compositional systems, combined using mechanisms within or outside the compositional
systems, with a corresponding 3D model.
3.2.5
virtual body part
medical entity (3.2.4) that constitutes
...