Objective: To investigate whether there is a correlation between active anterior rhinomanometry (RMM) and optical rhinometry (ORM) data in the detection of changes in nasal congestion.Design: In 70 subjects both ORM and RMM were performed. Changes in nasal congestion were induced by nasal provocation with histamine, allergens, solvent, and xylometazoline hydrochloride, 0.1%. Using visual analog scales, subjects rated the degree of nasal congestion and how comfortable each of the 2 measures was. In total, 136 measurements were evaluated.Subjects: Seventy subjects were included in the study. All had a normal otorhinolaryngologic status with no acute or chronic infections.Interventions: Nasal provocation tests with allergens, histamine, control solution, or xylometazoline were performed.Main Outcome Measures: Congestion or decongestion of the nasal mucosa was measured via nasal resistance (RMM), changes in light absorption of the nasal tissue (ORM), and visual analog scale.Results: When comparing the relative change in light extinction in ORM with nasal airflow in RMM, we found correlation coefficients up to r=-0.69. Results from RMM were correlated with the subjects' ratings of nasal congestion (r=-0.63). In comparison, the correlation coefficient between these ratings and ORM was r=0.84. In addition, ORM was rated to be more comfortable than RMM.Conclusions: The subjects' ratings of nasal congestion correlated to a higher degree with the results from ORM than with those from RMM. In addition, ORM was rated as more comfortable than RMM. Overall, ORM appeared to be a valid technique for the assessment of changes in nasal congestion.