Acoustic rhinometry assessment of the nasal cycle in neonates.

In this study the nasal cycle in newborns was assessed using acoustic rhinometry with miniprobe (RHIN 2100). Enrolled in the study were 67 newborns aged 2 to 4 days. Each subject was assessed for 3 h, examinations taking place every 30 min. At least six measurements, three from each nostril, were taken at each examination. The miniprobe RHIN 2100 (SR Electronics ApS) was used for evaluation of nasal geometry. The minimal cross-sectional area (MCA) and the total volume of the anterior 45 mm (VOL45) were calculated and used for statistical analysis. The mean volume of MCA and VOL45 in the examined group of children was 0.08 cm3 and 1.19 cm3 respectively. Nasal cycle was assessed by constructing the plots of acoustic rhinometry parameters MCA or VOL45 for time and statistically using Pearson's correlation coefficients. Most of the examined infants (70-85%) showed no significant fluctuations in nasal patency.