To study nasal physiologic responses to changes in posture, temperatures, humidity and nasal patency with acoustic rhinometry.

The purpose of this study was to utilize acoustic rhinometry to assess changes in nasal patency after alterations in posture, unilateral mechanical obstruction, temperature, and humidity.

Eight healthy adult volunteer subjects underwent acoustic rhinometry under the following conditions: 1) upright, sitting position (control), 2) supine position, 3) left lateral recumbent position, 4) one nostril mechanically blocked, 5) icepack on neck, 6) drinking cold water, 7) drinking hot water, 8) nasal nebulizer, 9)oxymetazoline decongestant.

Changes in nasal cavity volumes were detected by acoustic rhinometry after alterations in posture, unilateral mechanical obstruction, temperature, and humidity. Nebulizer treatment and hot water ingestion caused a significant decrease in nasal volume. The nose was able to adapt to environmental and physiological changes in order to maintain a consistent total nasal volume.

Inclusion Criteria:

• Healthy volunteers, 18-58 years old

Exclusion Criteria:

• Any nasal symptoms in the last 3 weeks
• Marked septal deviation/polyposis/infection
• Any history of allergy, asthma or immunodeficiency
• Any systemic condition or infection (e.g., hypertension/diabetes/heart, liver, thyroid or kidney disease
• Any spine or neck condition that would not allow normal postures
• Pregnancy