Comparison of nasal volume changes during rapid maxillary expansion using acoustic rhinometry and computed tomography.

The purpose of this study was to compare nasal volume changes using acoustic rhinometry (AR) and computed tomography (CT). The subjects were 10 children (6 girls and 4 boys, with an age range of 12-14 years) who required rapid maxillary expansion (RME) on the basis of their individual malocclusion. All patients were found to have normal nasal cavities following anterior rhinoscopic examination. AR and CT were undertaken at the start of treatment (t(1)) and 6 months after expansion (t(2)). Volume changes due to expansion were evaluated using Wilcoxon's test, and the correlation between the two methods was assessed with correlation analyses. Both methods demonstrated that nasal volume significantly increased following the use of RME (P<0.05). Correlation analyses showed no difference in volume (P>0.05) using either of the two methods.