[Study on difference in olfactory response in dysosmia patients].

Area of Science:

• Otorhinolaryngology
• Neuroscience
• Olfactory Research

Background:

• Olfactory dysfunction (dysosmia) affects a significant portion of the population.
• Understanding differential odor perception in dysosmia is crucial for diagnosis and treatment.
• Standardized olfactory acuity tests are used to assess olfactory function.

Purpose of the Study:

• To investigate the differential olfactory response to five standard odorants in 1952 patients with dysosmia.
• To identify specific odorants that are more resistant to olfactory dysfunction or more likely to be recovered.
• To explore potential mechanisms underlying differential odor perception in olfactory disorders.

Main Methods:

• A cohort of 1952 patients with various etiologies of dysosmia was studied.
• The standard olfactory acuity test in Japan, using five specific odorants (beta-phenyl ethyl alcohol, methyl cyclopentenolone, isovaleric acid, gamma-undecalactone, scatol), was administered.
• Olfactory responses were assessed at both detection and recognition thresholds before and after treatment.

Main Results:

• Isovaleric acid was significantly more likely to be detected and recognized compared to other odors at both thresholds (p < 0.01).
• Patients who improved after treatment were significantly more likely to regain the ability to detect/recognize isovaleric acid only.
• No specific etiology strongly correlated with the ability to smell only isovaleric acid.

Conclusions:

• Olfactory function for detecting isovaleric acid appears relatively resistant to disease and most likely to be restored.
• Differential odor responses in dysosmia may be due to variations in olfactory receptor protein numbers or molecular responses.
• Isovaleric acid serves as a potential indicator for olfactory function resilience and recovery potential.