Olfactory Evaluation in Clinical Medical Practice.

Area of Science:

• Otorhinolaryngology
• Neuroscience
• Diagnostic Medicine

Background:

• Olfactory testing is often neglected in clinical practice despite smell loss significantly impacting daily life.
• Loss of olfaction is associated with a wide range of diseases beyond otorhinolaryngology, including neurodegenerative disorders.
• Understanding clinical testing is essential for diagnosing olfactory impairment and identifying underlying causes.

Purpose of the Study:

• To provide a comprehensive review of current clinical olfactory testing methods, including their benefits, limitations, and outcomes.
• To elucidate the mechanisms of olfaction and pinpoint potential sites of impairment within the olfactory pathway.
• To discuss the correlation between sinonasal microbiome, conditions like nasal polyposis and chronic rhinosinusitis, and olfactory dysfunction.

Main Methods:

• Review of existing literature, studies, and clinical experiences related to olfactory testing.
• Step-by-step analysis of the olfaction mechanism to understand error localization.
• Evaluation of methods assessing nasal cavity cross-sectional area and patency.
• Inclusion of subjective and objective assessments of olfactory function.
• Detailed discussion of objective olfactometry and olfactory event-related potentials (OERP).

Main Results:

• Olfactory impairment stems from issues in odour transfer or damage to olfactory structures.
• Comprehensive examination requires assessing nasal patency and olfactory function objectively and subjectively.
• The review highlights the utility of objective olfactometry and OERP in diagnosing smell disorders.
• Correlation between sinonasal microbiome and olfactory impairment in specific conditions is explored.

Conclusions:

• Accurate diagnosis of smell loss necessitates a thorough understanding of olfactory pathways and appropriate clinical testing.
• Objective olfactometry and OERP offer valuable tools for detailed assessment and differential diagnosis of olfactory dysfunction.
• Further research into the microbiome's role in olfactory impairment may reveal new diagnostic and therapeutic targets.