This monocentric, interventional study (category RIPH2) aims to characterize the rheological properties of sinonasal secretions in patients with Chronic Rhinosinusitis with Nasal Polyps (CRSwNP). The primary objective is to determine differences in mucus viscosity between CRSwNP patients and a control group. By establishing a correlation between local rheology and systemic Type 2 inflammation biomarkers, the study seeks to develop a non-invasive, rapid "point-of-care" tool to refine patient phenotyping and improve the personalization of biological treatments.