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Updated: Jul 19, 2026
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Olfactory Assays for Mouse Models of Neurodegenerative Disease
Published on: August 25, 2014
A study on the prognostic significance of qualitative olfactory dysfunction
1Smell and Taste Clinic, Department of Otorhinolaryngology, University of Dresden Medical School ("Technische Universität Dresden"), Fetscherstrasse 74, 01307, Dresden, Germany.
Summary
Qualitative olfactory dysfunction, such as parosmia and phantosmia, is common in patients with smell loss. These symptoms have limited prognostic value for olfactory recovery, though phantosmia resolves faster than parosmia.
Area of Science:
- Otolaryngology
- Neuroscience
Background:
- Qualitative olfactory dysfunction, including parosmia and phantosmia, affects patients with smell impairment.
- The prognostic significance of these distortions for olfactory recovery remains unclear.
Purpose of the Study:
- To investigate the frequency and prognostic value of parosmia and phantosmia in patients with olfactory dysfunction.
- To assess the impact of these qualitative symptoms on olfactory function recovery.
Main Methods:
- Retrospective study of 392 patients with olfactory impairment.
- Olfactory function assessed using "Sniffin' Sticks" at least twice over a mean interval of 11 months.
Main Results:
- Parosmia reported by 34% of patients, most common in postinfectious cases (56%).
- Phantosmia reported by 12% of patients, with no significant group differences.
- 23% of patients showed improved olfactory function; parosmia/phantosmia did not affect recovery rates.
- 29% of parosmia cases resolved; 53% of phantosmia cases resolved, with phantosmia resolving faster.
Conclusions:
- Parosmia and phantosmia have limited prognostic value for olfactory recovery.
- Phantosmia tends to resolve more quickly than parosmia.
- Understanding qualitative olfactory dysfunction is crucial for patient counseling regarding olfactory loss.
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