Abstract
BACKGROUND AND PURPOSE: While posttraumatic anosmia is not uncommon, the olfactory function evaluation has strongly relied on subjective responses given by patients. We aimed to examine the utility of fMRI as an objective tool for diagnosing traumatic anosmia.
MATERIALS AND METHODS: Sixteen patients (11 men and 5 women; mean age, 42.2 ± 10.4 years) with clinically diagnosed traumatic anosmia and 19 healthy control subjects (11 men and 8 women; mean age, 29.3 ± 8.5 years) underwent fMRI during olfactory stimulation with citral (a pleasant odor) or β-mercaptoethanol (an unpleasant odor). All patients were subjected to a clinical olfactory functional assessment and nasal endoscopic exploration. Two-sample t tests were conducted with age as a covariate to examine group differences in brain activation responses to olfactory stimulation (false discovery rate–corrected P < .05).
RESULTS: Compared with healthy control subjects, patients with traumatic anosmia had reduced activation in the bilateral primary and secondary olfactory cortices and the limbic system in response to β-mercaptoethanol stimulation, whereas reduced activation was observed only in the left frontal subgyral region in response to citral stimulation.
CONCLUSIONS: Brain activation was decreased in the bilateral primary and secondary olfactory cortices as well as the limbic system in response to olfactory stimulation in patients with traumatic anosmia compared with healthy control subjects. These preliminary results may shed light on the potential of fMRI for the diagnosis of traumatic anosmia.
ABBREVIATIONS:
- BME
- β-mercaptoethanol
- BOLD
- blood oxygen level–dependent
- CC-SIT
- Cross-Cultural Smell Identification Test
- HC
- healthy control
- KVSS
- Korean Version of the Sniffin' Sticks
- MNI
- Montreal Neurological Institute
Footnotes
Disclosures: Jin Kook Kim—RELATED: Grant: This research was supported by the Basic Science Research Program through the National Research Foundation of Korea funded by the Ministry of Education (NRF-2016R1D1A1B01012705)*. *Money paid to the institution.
This research was supported by Basic Science Research Program through the National Research Foundation of Korea (NRF) funded by the Ministry of Education (NRF-2016R1D1A1B01012705).
Paper previously presented as a scientific poster at: Annual Meeting of the Radiological Society of North America, November 27 to December 1, 2016; Chicago, Illinois.
- © 2018 by American Journal of Neuroradiology
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