ACOUSTIC RHINOMETRY IN THE STUDY OF THE ACUTE NASAL ALLERGIC RESPONSE

Acoustic rhinometry is a recently developed method for the objective a ssessment of nasal patency. In this study, acoustic rhinometry was use d to measure changes in nasal cavity dimensions in the immediate respo nse to nasal allergen challenge in eight pollen-sensitive subjects. Ac oustic rhinometric changes were compared with subjective symptoms, as well as histamine in nasal secretions, cytology of nasal mucosal scrap ings, and changes in olfactory function. A significantly greater decre ase in nasal airway caliber occurred following allergen challenge as c ompared to buffer diluent challenge in the same individuals (70%+/-7% versus 22%+/-5%). During an allergic response, a strong correlation wa s found between the minimum cross-sectional area and the volume of the nasal cavity measured by acoustic rhinometry (r=.9). However, no corr elation was observed between nasal airway caliber and concomitant subj ective congestion reported by the subjects. A modest decrease in olfac tory function was seen following allergen challenge (3.1+/-1.4 fewer o dors identified correctly out of 20; p=.08). However, the alterations of olfactory function did not correlate with changes in nasal patency. The results presented in this study demonstrate that acoustic rhinome try has great potential as a reproducible method for the objective ass essment of nasal obstruction occurring in nasal allergen challenge stu dies.