Abstract

BACKGROUND:

Each ethnic group has different nasal cavity geometries. The reference value of the minimal cross-sectional area (MCA) and the nasal volume (NV) is mandatory for rhinologic evaluation in regular practice and for research. This study was designed to study the normal value of acoustic rhinometry (AR) in Asian subjects in comparison with other ethnic groups.

METHODS:

AR was performed in 135 healthy Thai subjects. Subjects were divided into two groups: group I, with normal anterior rhinoscopic appearance; group II included subjects with asymptomatic, slightly deviated nasal septa.

RESULTS:

The mean of the MCA was 0.61 +/- 0.60 cm2 before decongestion and 0.64 +/- 0.14 cm2 after decongestion. The mean distance from the nostril to the point of MCA (D) was 1.66 +/- 0.59 cm before decongestion and 1.41 +/- 0.74 cm after decongestion. The mean of the NV measured between 0 and 4 cm was 3.66 +/- 0.67 cm3 before decongestion and 4.18 +/- 0.75 cm3 after decongestion. Before decongestion, there were no significant differences in the mean of the MCA, D, and NV between group I and group II subjects; however, there were significant differences in mean MCA and NV after decongestion. There were no differences in the parameters between male and female subjects before decongestion, except for the D, but after decongestion the mean values of the MCA, D, and NV were significantly higher in male subjects compared with female subjects.

CONCLUSION:

The results of this study can be used as a reference value for Asian ethnicities. Thai subjects had measurements comparable with those of the European study and somewhat different from the study in black populations.