Nasal Patency Measurement: State of the Art of Acoustic Rhinometry.

Nasal obstruction is one of the main symptoms of different nasal pathologies. Many physiological and pathological conditions can produce nasal airflow impairment causing nasal obstruction and affecting patients' quality of life. There are different methods for the measurement of nasal obstruction, but in clinical practice the most common used are acoustic rhinometry, rhinomanometry, and peak nasal inspiratory flow. This review describes the fundamentals of acoustic rhinometry, its normal values, the different physiological and pathological conditions that can modify nasal patency, and the utility of this instrument for the measurement of nasal obstruction in clinical practice. Acoustic rhinometry is a simple test, so it is suitable for measurements in the pediatric population, i.e., for evaluating adenoid hypertrophy. Acoustic rhinometry normal values are available, unilaterally and bilaterally for pediatric and adult populations. Acoustic rhinometry has been demonstrated to be reproducible and even superior to rhinomanometry when measuring nasal modifications during challenges. It is possible to use acoustic rhinometry before and after nasal surgery. Measuring nasal cavities volume and cross-sectional area, acoustic rhinometry is particularly indicated in rhinosurgery, especially for the evaluation of spreader grafts. Brief considerations about the correlation between nasal symptoms, in particular the subjective sensation of nasal obstruction, and the acoustic rhinometry results as well as the correlation of acoustic rhinometry with other methods for the measurement of nasal obstruction are also reported. Objective and subjective evaluation of nasal obstruction gives different information that together optimizes the diagnosis and the treatment of rhinologic patients. Acoustic rhinometry alone or in combination of other instruments for the measurement of nasal obstruction or patency should be used regularly in every outpatient clinic that treats patients with nasal obstruction as there is an increasing need of evidence-based therapies.