Measurement of Nasal Trigeminal Pungency Threshold: Comparison between Normals and Patients with Decreased Sense of Smell

ABSTRACT

BACKGROUND AND OBJECTIVES: In order to measure the level of nasal trigeminal pungency threshold and to evaluate the interaction between olfactory and trigeminal nerves, we measured olfactory thresholds and trigeminal pungency thresholds using 1-butanol in 40 normal people and in 46 patients with decreased sense of smell by non-sinonasal origin. MATERIALS AND METHODS: Two-alternative forced-choice modified ascending method of limit (CCCRC test) was used for the measurement of olfactory and pungency thresholds, using 1-butanol plastic squeezable bottles successively threefold diluted by distilled water as stimulus, while distilled water as blank. RESULTS: There was a statistically significant difference in pungency threshold between normals (2.18+/-1.5 dilution step) and patients (1.11+/-1.0 dilution step)(p<0.001). CONCLUSION: The pungency thresholds of hyposmics and anosmics are higher than those of normals, which suggests that a loss or decrease of olfactory sensation is accompanied by a simultaneous decrease of trigeminal chemosensitivity.