Respiratory rhinometry, a review of recent trends.

Rhinometry of respiratory airflow is discussed and disadvantages of invasive methods are emphasized. The stability of the series of pressure-flow relationships of respiratory air which is repeated through consecutive nasal breaths may be exploited to provide an index of nasal obstruction-different techniques and their limitations are outlined. The use of an inexpensive microprocessor interfaced with standard respiratory laboratory pressure and flow measuring apparatus is described and advocated for assessment of resistance to respiratory airflow in the nasal cavities and other flow resistant segments of the airways.