Measurements of cross-sectional area of the nasal cavity by acoustic rhinometry and CT scanning.

The authors aimed to evaluate the validity and characteristics of acoustic rhinometic tests by comparing the results with those of computed tomography (CT) of the nasal cavity. Cross-sectional areas along the nasal cavity were measured by acoustic rhinometry (AR) and CT of the nasal cavity in 30 normal subjects. Cross-sectional areas measured by each technique showed a statistically significant correlation. The two measurements showed a better linear correlation in the anterior part of the nasal cavity up to 24 mm from the nostril than in the posterior part of the nasal cavity beyond that point. Mean cross-sectional areas measured by AR were constantly less than those measured by CT of the nasal cavity up to 33 mm from the nostril, whereas areas measured by AR were greater than those measured by CT scans beyond that point.