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Updated: May 16, 2026
10:42
A Free-breathing fMRI Method to Study Human Olfactory Function
Published on: July 30, 2017
[Analysis of clinical characteristics of partial olfactory dysfunction]
Jing Guan1, Dao-feng Ni, Jian Wang
1Department of Otolaryngology, Chinese Academy of Medical Sciences, Beijing, China.
Zhonghua Yi Xue Za Zhi
|November 20, 2012
Summary
Partial olfactory dysfunction may present with normal overall smell function but abnormal responses to specific odors. This subtle impairment can be easily overlooked during standard smell testing.
Area of Science:
- Otorhinolaryngology
- Neuroscience
- Sensory Science
Background:
- Olfactory dysfunction is a common symptom impacting quality of life.
- Partial olfactory dysfunction, characterized by subtle smell impairments, poses diagnostic challenges.
Purpose of the Study:
- To investigate the clinical characteristics of partial olfactory dysfunction using the T&T olfactometer.
- To evaluate the utility of different odorant types and concentrations in assessing smell function.
Main Methods:
- 24 patients with olfactory dysfunction underwent comprehensive evaluation, including history, physical examination, and smell testing.
- Olfactory function was assessed using the T&T olfactometer with five odorants at varying concentrations.
- Recognition threshold (RT) scores were measured for individual odorants and overall smell function.
Main Results:
- Patients with partial olfactory dysfunction often exhibited normal total RT scores but significantly elevated RT scores for one or two specific odorants.
- Abnormalities were observed for both pleasant (51.4%) and unpleasant odors in patients with partial olfactory dysfunction.
Conclusions:
- Partial olfactory dysfunction is characterized by normal overall T&T olfactometer RT scores alongside abnormal single odorant RT scores.
- This specific pattern of olfactory impairment may be easily missed during routine smell assessments.
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