Functional MRI as an Objective Measure of Olfaction Deficit in Patients with Traumatic Anosmia
1Department of Radiology (W.-J.M., M.P.), Konkuk University Medical Center, Konkuk University School of Medicine, Seoul, Korea.
AJNR. American Journal of Neuroradiology
|November 10, 2018
Summary
Functional MRI (fMRI) shows reduced brain activation in patients with traumatic anosmia. This objective tool may aid in diagnosing olfactory dysfunction following head trauma.
Area of Science:
- Neuroscience
- Olfactory Research
- Medical Imaging
Background:
- Posttraumatic anosmia, or loss of smell after injury, is common.
- Current olfactory function evaluation relies heavily on subjective patient reports.
- Objective diagnostic tools for traumatic anosmia are needed.
Purpose of the Study:
- To evaluate functional magnetic resonance imaging (fMRI) as an objective diagnostic tool for traumatic anosmia.
- To compare brain activation patterns in patients with traumatic anosmia versus healthy controls.
Main Methods:
- fMRI was performed on 16 patients with traumatic anosmia and 19 healthy controls.
- Olfactory stimulation used pleasant (citral) and unpleasant (β-mercaptoethanol) odors.
- Group differences in brain activation were analyzed using t-tests, controlling for age.
Main Results:
- Patients with traumatic anosmia exhibited reduced activation in olfactory cortices and limbic system to unpleasant odors.
- Reduced activation was noted in the left frontal subgyral region for pleasant odors.
- Significant differences in brain activation were observed between groups.
Conclusions:
- fMRI demonstrates decreased brain activation in key olfactory processing areas in patients with traumatic anosmia.
- These findings suggest fMRI's potential as an objective method for diagnosing traumatic anosmia.
- Further research is warranted to confirm fMRI's diagnostic utility.
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