Importance of unilateral examination in olfactometry

Area of Science:

• Otolaryngology
• Neurology
• Sensory Science

Background:

• Hyposmia (decreased smell) and anosmia (loss of smell) can affect one or both sides of the nose.
• Bilateral olfactory tests may miss unilateral olfactory deficits, leading to underdiagnosis.
• Accurate assessment of olfactory acuity is essential for diagnosing various conditions.

Purpose of the Study:

• To emphasize the necessity of unilateral olfactometry for precise olfactory acuity evaluation.
• To demonstrate the clinical utility of unilateral olfactory testing in identifying subtle smell impairments.

Main Methods:

• Evaluation of olfactory thresholds in individual nasal cavities.
• Comparison of unilateral olfactory test results with patient-reported symptoms and clinical diagnoses.
• Case studies including patients with chronic rhinosinusitis, anterior cranial fossa surgery, and brain tumors.

Main Results:

• Significant differences in olfactory thresholds between nasal cavities were found in 7/94 chronic rhinosinusitis patients and 6/12 patients post-anterior cranial fossa surgery.
• No patients with unilateral high olfactory thresholds reported a diminished sense of smell, highlighting the limitations of subjective assessment.
• Unilateral olfactory testing aided in the diagnosis of a brain tumor case.

Conclusions:

• Unilateral olfactometry is a simple, reliable method for clinical measurement of olfactory function.
• This technique is vital for detecting unilateral olfactory disorders that bilateral tests may overlook.
• The study strongly recommends implementing unilateral olfactometry in clinical practice for comprehensive smell assessment.