Olfactory Nomenclature: An Orchestrated Effort to Clarify Terms and Definitions of Dysosmia, Anosmia, Hyposmia, Normosmia, Hyperosmia, Olfactory Intolerance, Parosmia, and Phantosmia/Olfactory Hallucination

Anna Kristina Hernandez; Basile N Landis; Aytug Altundag; Alexander Wieck Fjaeldstad; Simon Gane; Eric H Holbrook; Caroline Huart; Iordanis Konstantinidis; Matt Lechner; Alberto Macchi; Patricia Portillo Mazal; Takaki Miwa; Carl M Philpott; Jayant M Pinto; Sophia C Poletti; Jan Vodicka; Antje Welge-Luessen; Katherine L Whitcroft; Thomas Hummel

doi:10.1159/000530211

Olfactory Nomenclature: An Orchestrated Effort to Clarify Terms and Definitions of Dysosmia, Anosmia, Hyposmia, Normosmia, Hyperosmia, Olfactory Intolerance, Parosmia, and Phantosmia/Olfactory Hallucination

ORL J Otorhinolaryngol Relat Spec. 2023;85(6):312-320. doi: 10.1159/000530211. Epub 2023 Apr 14.

Authors

Anna Kristina Hernandez^{1

2

3}, Basile N Landis⁴, Aytug Altundag⁵, Alexander Wieck Fjaeldstad^{6

7

8

9}, Simon Gane^{9

10}, Eric H Holbrook¹¹, Caroline Huart^{12

13}, Iordanis Konstantinidis¹⁴, Matt Lechner^{15

16

17}, Alberto Macchi¹⁸, Patricia Portillo Mazal¹⁹, Takaki Miwa²⁰, Carl M Philpott^{21

22}, Jayant M Pinto²³, Sophia C Poletti²⁴, Jan Vodicka²⁵, Antje Welge-Luessen²⁶, Katherine L Whitcroft^{1

9

27}, Thomas Hummel¹

Affiliations

¹ Smell and Taste Clinic, Department of Otorhinolaryngology, Faculty of Medicine Carl Gustav Carus, Technische Universität Dresden, Dresden, Germany.
² Department of Otolaryngology - Head and Neck Surgery, Philippine General Hospital, University of the Philippines - Manila, Manila, Philippines.
³ Department of Otolaryngology - Head and Neck Surgery, Asian Hospital and Medical Center, Muntinlupa, Philippines.
⁴ Rhinology-Olfactology Unit, Department of Otorhinolaryngology, University Hospital of Geneva, Geneva, Switzerland.
⁵ Department of Otolaryngology, Head and Neck Surgery, Biruni University Medical School, Istanbul, Turkey.
⁶ Department of Otorhinolaryngology, University Clinic for Flavour, Balance and Sleep, Regional Hospital Gødstrup, Herning, Denmark.
⁷ Department of Clinical Medicine, Flavour Institute, Aarhus University, Aarhus, Denmark.
⁸ Center for Eudaimonia and Human Flourishing, Linacre College, University of Oxford, Oxford, UK.
⁹ The Centre for Olfactory Research and Applications, Institute of Philosophy, School of Advanced Study, University of London, London, UK.
¹⁰ Royal National Throat Nose and Ear Hospital, UCLH, London, UK.
¹¹ Department of Otolaryngology, Massachusetts Eye and Ear, Boston, Massachusetts, USA.
¹² Department of Otorhinolaryngology, Cliniques Universitaires Saint-Luc, Brussels, Belgium.
¹³ Institute of Neuroscience, Université Catholique de Louvain, Brussels, Belgium.
¹⁴ Smell and Taste Clinic, Second Academic Otorhinolaryngology Department, Papageorgiou Hospital, Aristotle University of Thessaloniki, Thessaloniki, Greece.
¹⁵ Division of Surgery and Interventional Science, University College London, London, UK.
¹⁶ UCL Cancer Institute, University College London, London, UK.
¹⁷ ENT Department, Homerton Healthcare NHS Foundation Trust, London, UK.
¹⁸ ENT Clinic, University of Insubria, ASST Sette Laghi, Varese, Italy.
¹⁹ Servicio de Otorrinolaringología, Hospital Italiano de Buenos Aires, Buenos Aires, Argentina.
²⁰ Department of Otorhinolaryngology, Kanazawa Medical University, Uchinada, Japan.
²¹ Norwich Medical School, University of East Anglia, Norwich, UK.
²² The Smell and Taste Clinic, James Paget University Hospital, Gorleston, UK.
²³ Section of Otolaryngology-Head and Neck Surgery, The University of Chicago Medicine and Biological Sciences, Chicago, Illinois, USA.
²⁴ Department of Otorhinolaryngology, Head and Neck Surgery, Inselspital, Bern University Hospital, University of Bern, Bern, Switzerland.
²⁵ Department of Otorhinolaryngology and Head and Neck Surgery, Hospital Pardubice, Faculty of Health Studies, University of Pardubice, Pardubice, Czechia.
²⁶ Department of Otorhinolaryngology, University Hospital Basel, Basel, Switzerland.
²⁷ UCL Ear Institute, Faculty of Brain Sciences, University College London, London, UK.

Abstract

Background: Definitions are essential for effective communication and discourse, particularly in science. They allow the shared understanding of a thought or idea, generalization of knowledge, and comparison across scientific investigation. The current terms describing olfactory dysfunction are vague and overlapping.

Summary: As a group of clinical olfactory researchers, we propose the standardization of the terms "dysosmia," "anosmia," "hyposmia," "normosmia," "hyperosmia," "olfactory intolerance," "parosmia," and "phantosmia" (or "olfactory hallucination") in olfaction-related communication, with specific definitions in this text.

Key messages: The words included in this paper were determined as those which are most frequently used in the context of olfactory function and dysfunction, in both clinical and research settings. Despite widespread use in publications, however, there still exists some disagreement in the literature regarding the definitions of terms related to olfaction. Multiple overlapping and imprecise terms that are currently in use are confusing and hinder clarity and universal understanding of these concepts. There is a pressing need to have a unified agreement on the definitions of these olfactory terms by researchers working in the field of chemosensory sciences. With the increased interest in olfaction, precise use of these terms will improve the ability to integrate and advance knowledge in this field.

Keywords: Anosmia; Definition; Dysosmia; Hyperosmia; Hyposmia; Normosmia; Olfaction; Olfactory hallucination; Olfactory intolerance; Parosmia; Phantosmia.

Publication types

Review
Research Support, Non-U.S. Gov't

MeSH terms

Anosmia
Hallucinations
Humans
Olfaction Disorders* / diagnosis
Smell*

Grants and funding

T.H. and A.K.H. are supported by a grant from the Deutsche Forschungsgemeinschaft (DFG HU 441/21-1; project number 468981129).