The nasal partition data (NPR) can be used to compare the symmetry to air flow between the left and right nostril.
Parameter:
(1) measure of airflow through the left nostril
(2) measure of airflow through the right nostril
Airflow can be measured:
(1) nasal spirometry or rhinomanometry
(2) qualitative by scale (for example from 0 to 10)
nasal partitioning ratio =
= ((flow through left nostril) - (flow through right nostril)) / ((flow through left nostril) + (flow through right nostril))
Interpretation:
• minimum score: -1
• maximum score: +1
• Symmetrical airflow has an NPR of 0.
• Maximal flow in the left nostril with no flow in the right has an NPR of +1.
• Maximal flow in the right nostril with no flow in the left has an NPR of -1.
Limitations:
• The NPR does not define how normal airflow is through the left or right nostril. This would be a additional information that needs to be specified, especially if comparing pre- and post-procedural change.