EAU Standardised Medical Terminology for Urologic Imaging: A Taxonomic Approach

Transcription

1 EAU Standardised Medical Terminology for Urologic Imaging: A Taxonomic Approach T. Loch (Chair), B. Carey, J. Walz, P.F. Fulgham European Association of Urology 2016

2 TABLE OF CONTENTS PAGE 1. INTRODUCTION 3 2. METHODS Rationale for a taxonomic approach 4 3. RESULTS 4 4. DISCUSSION Rationale for advocating the use of a unified nomenclature Guidelines 9 5. CONCLUSIONS Appendices ACKNOWLEDGMENT STATEMENT REFERENCES CONFLICT OF INTEREST 11 2

3 1. INTRODUCTION The continued development of new imaging techniques in urology has had considerable impact on both clinical practice and urologic research [1, 2]. The clinical integration of these imaging techniques into urologic practice involves contributions from investigators and clinicians of varied backgrounds including physics and engineering, informatics, urology, and radiology. Each profession has its own jargon, a specialised language that allows for rapid and efficient communication between members of the same profession while minimising the potential for misunderstandings. Abbreviations are an extension of the jargon of each profession, and they enable health care professionals to document their work more easily and communicate quickly. Abbreviations have generally been adopted on an ad hoc basis to accommodate the often conflicting demands of utilising brief context-sensitive phrases and combinations of letters with the challenging requirements of more rigid, computer software-driven, clinical and research practice; however, this jargon might lead to the problem of several terms for the same object. The differences in terminology and the lack of standardisation of the terminology can lead to confounders, errors, and misunderstandings as well as to loss of information and knowledge. Most of this development and expansion of terminology has occurred in an unplanned and uncoordinated manner and has been adopted through common usage within specialities rather than by consensus agreement [3]. Various lists of abbreviations and terminologies have been produced by different speciality groups [4, 5]. During the review, it was found that a wide variety of terms were used for the same examination, for example, Intravenous Urogram (IVU) was also termed Kidney, Ureter, Bladder (KUB) Urogram or Urography. Much of this usage has been driven by agreed common practice without reference to any unifying standard of methodology or taxonomy. Taxonomy is a general principle of scientific classification. Organisms are classified into a hierarchy of groupings. The order of ranking is usually from the more general to the more specific to describe and reflect a morphologic relationship [6]. There has been a general lack of international co-operation among different specialities and among different geographic locations for the same speciality. Confusion between the different requirements for digital archive coding systems and research may cause a lack of support to integrate data produced by everyone involved in urology imaging and further promote a diversity of interests. The benefits of a shared nomenclature for literature research and communication among clinicians are obvious. The absence of agreed on operational nomenclature will inevitably undermine the yield from literature review if different search terms are used. The aim of this work is to review the current nomenclature used for imaging in urology in clinical practice and in the published literature and to propose standardisation of terms using taxonomy. 2. METHODS The list of terms used for urologic imaging was compiled from guidelines published by the European Association of Urology (EAU) [7], the American Urological Association (AUA) [8], and the American College of Radiology (ACR) [9]. These guidelines are regularly updated and based on extensive review of the current literature. A review of the different guideline texts, which included the terminology and abbreviations found in the reference listings for each guideline, showed that the same examination might have a variety of names. As noted, IVU was also called KUB urogram or urography. To investigate the terms used, the AUA and EAU guidelines and all of the urology-related ACR Appropriateness Criteria were downloaded into single directories. Using the advanced search feature of Acrobat Pro (CTRL- SHIFT-F; Adobe Systems Inc., San Jose, CA, USA), we searched for the terms, for example, CT or computed tomography (identical methodology for all other terms) and identified all of the various terms, abbreviations, and variants associated with them. Once the terms were identified, each term was then grouped by its operating characteristics. Specifically, terms were divided by the type of study (e.g., computed tomography 3

4 [CT]), anatomic extent (e.g., area researched such as abdomen or pelvis), the use of contrast and phases, the technique or type of detector (e.g., multiphase, helical, low dose), and combined studies or fusions (e.g., positron emission tomography [PET], CT). Based on the frequency of use and expert consensus, the terms were then placed in an accepted category or an equivalent or similar category. The categories were ranked by frequency of use within the documents. Imaging terms were grouped into broad categories based on technology (e.g., plain radiography, CT, ultrasound, magnetic resonance imaging [MRI], and nuclear medicine). Within each broad category, the imaging terms were further stratified based on the anatomic extent, contrast or phases, technique or modifiers, and combinations or fusions. Terms that had a high degree of utilisation were classified as accepted. Other terms were judged to be similar but were either infrequently used or contained modifiers requiring further explanation. To construct a general methodology for nomenclature adaptation in medical terminology, we propose that a taxonomy-based approach would help define a more useful model that would be acceptable to all health professionals involved in urology. 2.1 Rationale for a taxonomic approach The major advantage of a taxonomic approach to the classification of urologic imaging studies is that it provides a flexible framework for classifying the modifications of current imaging modalities and allows for the incorporation of new imaging modalities. Adopting this hierarchical classification model (i.e., from the most general to the most detailed descriptions) should facilitate hierarchical searches of the medical literature using both general and very specific search terms. 3. RESULTS Tables 1-7 summarise the findings of the systematic search for all major types of urologic imaging studies: ultrasound (US); CT; MRI; fluoroscopy; radiographs; PET, in combination with either CT (PET-CT) or MRI (PET MRI); and scintigraphy. In the tables, the most commonly used term is listed as the accepted standard, and less frequently used terms are listed under glossary of other terms, which should be replaced by the accepted standard. Table 1: Taxonomic classification of ultrasound Accepted standard Root Name Anatomic extent Contrast / phases Ultrasound US Kidney Ureter Bladder Penis Testis Scrotum Prostate Vas Vessels Non-contrast Contrast TRUS Transvaginal Transurethral Transvesical Intra-abdominal Transabdominal Technical modifiers / postprocessing methods Elastography C-TRUS/ANNA Histoscanning Doppler Colour Doppler Power Doppler Spectral Doppler Compound imaging Harmonic Combinations/ fusions MRI CT 4

5 Glossary of terms less widely accepted (descending order based on use in current Ultrasonography Sonography Endosonography Percutaneous ANNA = artificial neural network analysis; CT = computed tomography; C-TRUS = computerised transrectal ultrasound; MRI = magnetic resonance imaging; TRUS = transrectal ultrasound; US = ultrasound. Example: US, prostate, TRUS, C-TRUS/ANNA fused with MRI. Table 2: Taxonomic classification for computed tomography Accepted standard Glossary of terms less widely accepted (descending order based on use in current Root Name Computed tomography CT Computer tomography Computeraided tomography scan CAT scan CT scan Scan Anatomic extent Chest and pelvis Contrast / phases Technical modifiers Combinations / fusions Contrast Non-contrast urography Contrast-enhanced CT Non-contrast CT Non-enhanced CT Unenhanced CT Unenhanced spiral CT CT cystography CT angiography CT scout Intravenous CT angiography Three-phase helical CT Multiphasic Multidetector Multidetector row CT Single detector CT Multiphase CT Multiphasic CT Multiphasic CT urography Multiphasic CTU Low-dose CT Standard-dose CT Ultra-low-dose CT PET/CT CAT = computer-aided tomography; CT = computed tomography; CTU = computed tomography urography; PET = positron emission tomography. Example: CT, renal arteries, contrast, multiphasic. 5

6 Table 3: Taxonomic classification for magnetic resonance imaging Accepted standard Glossary of terms less widely accepted (descending order based on use in current Root Name Magnetic resonance imaging MRI Magnetic resonance MR Nuclear magnetic resonance NMR Anatomic extent Whole body Genitals Prostate Kidney Testis Penis Urinary tract Contrast / phases Technical modifiers Combinations / fusions T1 weighted (T1) T2 weighted (T2) Dynamic contrast enhanced Diffusion weighted imaging Spectroscopy Multiparametric MRI urography Contrast-enhanced MRI Non-enhanced MRI Unenhanced MRI MRI cystography MRI angiography Functional MRI Molecular MRI Molecular imaging 1.5 tesla (1.5T) 3 tesla (3T) 7 tesla (7T) Body array coil Rectal coil Surface coil Open-gantry MRI Regular-gantry MRI Interventional MRI Thermometrie PET/MRI DCE = dynamic contrast enhanced; DWI = diffusion weighted imaging; MP = multiparametric; MR = magnetic resonance; MRI = magnetic resonance imaging; NMR = nuclear magnetic resonance; PET = positron emission tomography. Example: MRI, prostate, T2, DCE, DWI, MP, 1.5T, surface coil. Table 4: Taxonomic classification of fluoroscopy Accepted standard Root Name Fluoroscopy Anatomic extent Chest Renal tracts Contrast / phases Non-contrast Contrast Glossary Fluorography of terms less widely accepted (descending order based on use in current CT = computed tomography. Example: Fluoroscopy, renal tract, contrast, intraoperative. Technical modifiers Combinations / fusions CT fluoroscopy Intraoperative Table 5: Taxonomic classification of radiographs Root Name Anatomic extent Contrast / phases Technical modifiers Combinations / fusions Accepted standard Radiographs Plain x-rays Intravenous urogram Chest Spine Extremities Renal tract Conventional Digital Antegrade Retrograde CT-urogram 6

7 Glossary of terms less widely accepted (descending order based on use in current Plain films radiography KUB Intravenous pyelogram Excretion urography Nephrostogram Kidneys Ureters Bladder Urethra Vas Plain Radiography CT Ascending Descending CT = computed tomography; IVU = intravenous urogram; KUB = kidney, ureter, and bladder. Example: IVU, renal tract, digital. CT-KUB CT-nephrostogram CT-urethrogram Table 6: Taxonomic classification of positron emission tomography in combination with either computed tomography or magnetic resonance imaging Accepted standard Glossary of terms less widely accepted (descending order based on use in current Accepted Standard Glossary of terms not to be used (descending order based on use in current Root Name Anatomic extent Technical modifiers Positron emission tomography computed tomography PET-CT CT-PET FDG-PET 18 FDG-PET PET FDG-PET CT Position emission tomography magnetic resonance imaging PET MRI PET/MRI PET-MRI Whole body Kidney Bladder Prostate Retroperitoneum Whole body Kidney Bladder Prostate Fluorodeoxyglucose 11 C-choline 18 Fluorine Methionine Other (non-specified) FDG Choline Acetate fluoro deoxy glucose 18 F-choline 11 C-acetate 18 F-acetate Other 18 FDG-PET = 18 fluorine-fluorodeoxyglucose positron emission tomography; CT = computed tomography; FDG = fluorodeoxyglucose; MRI = magnetic resonance imaging; PET = positron emission tomography. Example: PET CT,, 11 C- choline. 7

8 Table 7: Taxonomic classification of radiographs Accepted standard Glossary of terms less widely accepted (descending order based on use in current Root Name Anatomic extent Contrast / phases Combinations / fusions Scintigraphy Radionuclide scintigraphy Nuclear scintigraphy Radiographic scintigraphy Isotope scintigraphy Radioisotope scinitgraphy Bone Kidney Testis Bladder Bone scan Bone scintigraphy Renal scintigraphy Renal cortical scintigraphy Isotope renogram Isotope renography Scrotum scintigraphy Scintigraphy of the testis Radioisotope cystography 99m Technetium DMSA MAG3 DTPA Dimercaptosuccinic acid Mercaptuacetyltriglycine 3 Captopril scintigraphy 99mTc = 99m technetium; DMSA = dimercaptosuccinic acid; MAG3 = mercaptuacetyltriglycine 3; SPECT = single-photon emission computed tomography. Example: Scintigraphy, Bone, 99mTc. SPECT 4. DISCUSSION 4.1 Rationale for advocating the use of a unified nomenclature In our review of the terminology used for imaging studies in clinical urologic practice, research, and publication, we found that terms used for the same studies were not uniform (Supplementary Tables 1-3). We found that there is no standardised or recommended terminology for these imaging studies. There are more general, ongoing efforts to standardise the different vocabularies used in health care. The Unified Medical Language System (UMLS) [10] developed by the US National Library of Medicine is a set of files and software that link the major international terminologies into a common structure, allowing for efficient translation and interoperability. The UMLS currently includes vocabularies from about 140 different sources that can be used for the exchange of information. The Systematized Nomenclature of Medicine Clinical Terms (SNOMED CT) [11] is a reference terminology standard available through the UMLS consisting of concepts and terms and the interrelationships between them. The Health Terminology Standards Development Organisation is responsible for promoting the international adoption of SNOMED CT. It standardises the way health care terminology and data are recorded and aims to facilitate the coding, retrieval, analysis, aggregation, indexing, and exchange of clinical information across different health care entities. SNOMED CT was designed for use in software applications to represent clinically relevant information in a reliable and reproducible manner. In a similar way, different professional groups have adopted varying terminology for similar imaging investigations. Our ability to communicate effectively across medical and scientific disciplines may be hindered by inconsistent use or inadvertent misinterpretation of commonly used abbreviations and acronyms. These terminology variations are evident across different health care systems in different countries and across individual disciplines of clinical and scientific interest. There are a variety of abbreviations and synonyms for similar investigations, with overlapping definitions that can potentially confuse or misdirect clinicians and researchers (Supplementary Tables 1-3). The language of medicine is complex, and there is a justifiable need to avoid undue repetition and offer clarity to researchers and clinical specialists. Many abbreviations and acronyms that are readily understood within different professional disciplines may not be easily extrapolated to other areas of medical, and specifically urologic, practice. 8

9 The advent of the digital era in imaging has added a further layer of complexity to the terminology used for imaging procedures. The requirements of various digital systems to code and file huge volumes of imaging data has prompted the development of additional abbreviations and synonyms to organise and search for data within and between digital networks. Within these coding systems, individual studies are represented by specific identifiers, which are usually a combination of characters (letters and/or numbers) that have no meaning in themselves. This coded representation is then used in place of the natural language description of the concept for further computer or human processing. Standardised clinical vocabularies also generally include a coding system. An example of a coded system is MEDLINE s Medical Subject Headings [12]. Different professional groups (e.g., radiologists, urologists, health care providers) have ad hoc lists that have been adopted and incrementally amended in recent years. Large international databases such as the Cochrane Library [13] and Medline [14] have guidelines for the use of abbreviations and acronyms without being prescriptive or exclusive. The Cochrane Library, for example, advises using abbreviations and acronyms only if they are widely known and states that not using them would make literature reading tedious [13]. 4.2 Guidelines Panels charged with writing clinical guidelines must evaluate the existing literature regarding medical practice and make judgments, first, about the quality of the data and, next, about the clinical effectiveness of the procedure, the risks and harms associated with the procedure, and the costs of the procedure. Medical imaging is a complex technological procedure with many variables that affect efficacy, risk, and cost. It is difficult to evaluate the quality of the data when multiple terms describe the same imaging procedure and imaging procedures that share a common name but have vastly different operating characteristics (e.g., radiation dose, number of exposures). Evaluations of existing guidelines from the EAU, the AUA, and the ACR have demonstrated wide variability in terms associated with imaging. We have attempted to define the range of terms within the existing guidelines and then proposed a strategy for naming these imaging studies. The proposed strategy should improve the ability to compare outcome data using similar methodologies and ultimately will encourage the use of consistent terminology when constructing new guidelines [15]. In an effort to unify the terminology used in the imaging of urologic conditions, this EAU Imaging Panel compiled a list of terms commonly used in clinical and investigative urology. The Panel focused on terms most relevant to urology. Not included within the scope of this document are more general terms related to the details of imaging. These were considered to be already well understood and documented in the literature of their respective fields. Finally, terms that were considered interchangeable without being ambiguous or requiring further clarification were not considered for this document. 5. CONCLUSIONS The current list will form the basis for further discussion, development, and enhancement. The Expert Panel would like to stress that it has incorporated the most widely used terms across different specialities, avoiding any subjective selection of a term and aiming for objective selection of the most commonly used term for an imaging technique. Despite this, the proposed list (especially the glossary) is probably not complete. Consequently, the resulting list is not all-inclusive or comprehensive. The proposed terminology is intended to promote unified nomenclature in both clinical and research settings. It is not intended to be used for administrative and billing purposes. Different Health Care Administrative systems already have different agreed terminologies based on individual requirements, and our tables are not intended to replace these. It is anticipated that by adopting such a standardised terminology, all professional disciplines involved in the field of urologic imaging will benefit from better communication across specialities. In particular, for those involved in research, unified terminology should enhance the yield of evidence from literature searches and thus help promote the dissemination of findings as different professional groups publish within their own literature bases using commonly agreed terminology. 9

10 5.1 Appendices Appendix A. Practical points Details should be carefully noted, for example, consistency of punctuation is essential so that the term is IVU and not I.V.U. Nonspecific terms such as plain films should not be used. It may generally be helpful to write the name of the abbreviation or acronym in full, immediately followed by the abbreviated version or acronym in brackets: computed tomography (CT). A list of the most commonly used terms and abbreviations can be found online ( org/guidelines/eau-standardised-medical-terminology-for- urologic-imaging/). Appendix B. Supplementary data Supplementary data associated with this article can be found, in the online version, at: Loch T, et al. EAU Standardised Medical Terminology for Urologic Imaging: A Taxonomic Approach. Eur Urol (2015), org/ /j.eururo Reprinted with permission by Elsevier. 6. ACKNOWLEDGMENT STATEMENT This document was externally peer reviewed by representatives from several organisations (National Institute of Clinical Excellence, the European Society of Urologic Imaging, ad hoc panel members of the American Urological Association and the American College of Radiology) as well as the current chairmen of the European Association of Urology (EAU) guideline panels. This publication is the first approach addressing the issue of imaging terminology by the EAU Guidelines Office. The authors would like to thank the Guideline Office Board, the Panel Chairman, and the Central Office of the EAU for their constructive support during the process. 7. REFERENCES 1. Marberger, M., et al. Novel approaches to improve prostate cancer diagnosis and management in early-stage disease. BJU Int, Suppl 2: Loch, T. Novel strategies in imaging. World J Urol, : Mulla, M., et al. Terminology inaccuracies in the interpretation of imaging results in detection of cervical lymph node metastases in papillary thyroid cancer. Endocr Connect, : Moon, S., et al. A sense inventory for clinical abbreviations and acronyms created using clinical notes and medical dictionary resources. J Am Med Inform Assoc, : Komi, M., et al. Abbreviations of special terms for presentation/paper titles in magnetic resonance study. Nihon Hoshasen Gijutsu Gakkai Zasshi, : Toxonomy. Merriam-Webster Dictionary Website EAU guidelines. European Association of Urology Website Guidelines and policies. American Urological Association Website ACR Appropriateness Criteria. American College of Radiology Website Unified Medical Language System (UMLS). U.S. National Library of Medicine Website SNOMED CT. International Health Terminology Standards Devel-opment Organisation. Website Medical Subject Headings. U.S. National Library of Medicine Website. 10

11 13. Home page. The Cochrane Library Website Welcome to NCBI. U.S. National Library of Medicine Website Aus, G., et al. The European Association of Urology (EAU) guidelines methodology: a critical evaluation. Eur Urol, : CONFLICT OF INTEREST All members of the EAU Guidelines Ad-hoc guidelines working group on Urological Imaging have provided disclosure statements of all relationships that they have that might be perceived as a potential source of a conflict of interest. This information is publically accessible through the European Association of Urology website: This guidelines document was developed with the financial support of the European Association of Urology. No external sources of funding and support have been involved. The EAU is a non-profit organisation and funding is limited to administrative assistance and travel and meeting expenses. No honoraria or other reimbursements have been provided 11

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