Chapter 4 : Rhinomanometry and nasal challenge

The change in airway resistance along the nasal passage can be determined by passing a pressure sensing cannula carefully along the passage and determining the pressure-flow relationships during quiet breathing (Bridger and Proctor, 1970). Using this technique, Haight and Cole (1983b) clearly demonstrated that the major site of nasal resistance lies at the anterior end of the inferior turbinate just within the first few millimetres of the bony cavum as shown. The major site of nasal resistance occurs at the entrance of the piriform aperture. This site of maximum airway resistance agrees with the anatomical evidence and places the nasal valve at the isthmus nasi of the piriform aperture.