ACOUSTIC RHINOMETRY - DO WE NEED A STANDARDIZED OPERATING PROCEDURE

The usefulness of a standardized operating procedure for acoustic rhin ometry was assessed in a study on 51 healthy volunteers. Nasal measure ments were made with acoustic rhinometry before and after application of a topical nasal decongestant. Our standard operating procedure used three consecutive readings of anterior nasal volume to obtain a valid estimate of mean nasal dimensions. The mean measurement was only acce pted as valid if the three readings had a coefficient of variation (CV ) of less than 20%. Twenty-two out of 192 (11.5%) nasal cavities requi red more than three consecutive readings to achieve this. Our data sho w that the error encountered by relying on a single reading of an acou stic trace can be greater than the changes caused by the topical nasal decongestant and that multiple readings using a standard operating pr ocedure are essential to obtain valid data.