An interpretation method for objective assessment of nasal congestion with acoustic rhinometry

Acoustic rhinometry is a relatively new modality for evaluating the status of the nose. It assesses the geometry of the nasal cavity by analyzing reflected sound waves. Despite its expanding use, there is no established interpretation method. Our aims in the present descriptive study were to develop and test a protocol as a possible method to read these graphs for clinical use.

We formulated a reading protocol to grade the congestion state of the nasal cavity. The percentile difference of cross-sectional area and volume values between the baseline and decongested states were classified into five categories based on normative values.

Fifty-six patients with allergic rhinitis were used. All the acoustic rhinometry readings were performed in blinded fashion according to the protocol; later, the clinical information was paired with the interpretation of the graph.

The mean percentile differences of baseline and decongestion values in patients with allergic rhinitis were in the mild to moderate range difference according to our reading system. The range of nasal congestion in patients with allergic rhinitis patients was increased with additional pathological conditions such as sleep apnea.

The percentile difference between the baseline values and values for maximally decongested state reflect mucosal congestion as a "congestion factor," which can be graded as mild, moderate, severe, or markedly severe, for objective evaluation of nasal congestion.