Chronic Nasal obstruction (CNO) is not currently measurable objectively because clinicians use validated declarative self-questionnaires whose results are linked to the level of understanding, the acute or chronic clinical situation, fatigue, psychological state and the desired gain. Using numerical simulations of the passage of air in the nasal cavities determining specific airflow parameters, the respiratory comfort of healthy subjects and the CNO of patients treated for this pathology could be explained.

CNO concerns 20 to 25% of the general population due to numerous etiologies (septal deviation, polyps, chronic rhinosinusitis, post-therapeutic cancer quality of life…). It disrupts sleep and deteriorates all the compartments of the quality of life sometimes to depression. To date, nobody knows the exact component of CNO which is probably the amalgamation of different mucosal information and all measurement attempts have failed by lack of reliability and reproducibility. This major shortcoming of CNO quantification leads to diagnosis uncertainties, quantification of symptoms and therapeutic. The place of such complementary exam able to do an objective measure of NO is expected by the profession. The Computational Fluid Dynamic Simulation (CDFS) of the air passage would allow a complementary functional analysis to anatomy of the sino-nasal cavities to measure CNO. Such information would reduce the failure rate and unnecessary functional surgeries by 25%, reduce the inappropriate care of patients suffering to obstructive sleep disorders and reduce the financial burden on the health system. No patient follow-up in this study: pseudo-anonymized retrospective clinical and scannographic data from the routine management of patients in rhinosinusology consultations.

Inclusion Criteria:

• 18 years ≤ age < 70 years
• BMI < 30 kg/m2
• Subject or Patient of Caucasian ethnic origin or from the Mediterranean region.
• Asymptomatic subject with or without a septal deviation without sinonasal disease with a NOSE score ≤ 7 Or Patient suffering from chronic nasal obstruction of morphological origin (symptomatic septal or nasoseptal deviation) requiring surgical management with a NOSE score ≥ 9/20, without or .with sleep apnea with an Apnea-hypopnea index ≤ 20 with no other cause than this apnea syndrome

Exclusion Criteria:

• Acute or chronic rhinosinusitis with or without polyps (except controlled allergic rhinitis)
• Vasculitis
• Empty nasal cavity syndrome
• Septal perforations
• History of nasal plastic surgery, sinonasal endoscopic surgery and cancer with head or neck radiotherapy
• Uncontrolled bronchopulmonary pathology
• Treatments with nasal vasomotor repercussions.

participant with or without chronic nasal obstruction seen in the rhinology department of Bordeaux University Hospital