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Updated: Aug 24, 2025

A Free-breathing fMRI Method to Study Human Olfactory Function
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A Free-breathing fMRI Method to Study Human Olfactory Function

Published on: July 30, 2017

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Functional Imaging in Olfactory Disorders

V Van Regemorter1,2, Ph Rombaux1,3, L Dricot1

  • 1Institute of Neuroscience, Université catholique de Louvain, Brussels, Belgium.

Current Otorhinolaryngology Reports
|October 24, 2022
PubMed
Abstract

Insights

Functional MRI (fMRI) shows promise for diagnosing olfactory dysfunction (OD) by revealing altered brain activity. However, variability currently limits its routine clinical application for OD assessment.

Area of Science:

  • Neuroscience
  • Medical Imaging
  • Otolaryngology

Background:

  • Olfactory dysfunction (OD) significantly impacts quality of life.
  • Current diagnostic methods for OD are often subjective.
  • Objective biomarkers for OD are needed.

Purpose of the Study:

  • To synthesize findings on functional MRI (fMRI) for assessing olfactory dysfunction (OD).
  • To evaluate the potential of fMRI as a reliable clinical diagnostic tool for OD.

Main Methods:

  • Review of studies utilizing fMRI to investigate brain responses to olfactory stimulation in individuals with OD.
  • Analysis of functional connectivity alterations in patients with OD.
  • Assessment of trigeminal chemosensory system processing via fMRI.

Main Results:

  • Patients with quantitative OD show altered activation in olfactory and non-olfactory brain regions.
  • Parosmic patients exhibit complex patterns of reduced and heightened brain signals.
  • fMRI suggests potential decline in central trigeminal chemosensory processing in OD.
  • Altered functional connectivity correlates with olfactory performance.

Conclusions:

  • fMRI is a promising objective tool for evaluating OD.
  • High inter-individual variability in fMRI results currently hinders routine clinical diagnostic use.
  • Future research should optimize fMRI stimulation and analysis methods for OD.
Keywords:
Brain networkFunctional MRINeuroimagingOlfactory dysfunctionOlfactory trainingParosmia

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