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Updated: Jul 13, 2026

Symptom Assessment of Patients with Allergic Rhinitis Using an Allergen Exposure Chamber
Published on: March 3, 2023
Removing nasal valve obstruction in peak nasal inspiratory flow measurement
Martyn L Barnes1, Brian J Lipworth
1Asthma and Allergy Research Group, Department of Medicine and Therapeutics, Ninewells Hospital and Perth Royal Infirmary, University of Dundee, Dundee, Scotland. mbarnes@rcsed.ac.uk
Background:
Peak nasal inspiratory flow (PNIF) measurements are used to evaluate nasal obstruction and as a surrogate for disease activity in allergic rhinitis and other nasal complaints. This measurement can give erroneous results when forced inspiration leads to nasal valve collapse.
Objective:
To determine the effects of 2 different nasal stents (Sinuscone and Nozovent) on valve collapse and repeatability of PNIF measurements.
Methods:
Repeated measurements of PNIF were obtained in 74 individuals with and without 2 different nasal stents: Sinuscone and Nozovent.
Results:
The mean (95% confidence interval) improvement in PNIF was 1.7 L/min (-2.4 to 5.8 L/min; P = .42) with Nozovents and 25.4 L/min (11.4 to 39.4 L/min; P = .001) with Sinuscones. The PNIF coefficient of variation for repeatability was 11.6% without stents, 16.0% using Nozovents, and 10.4% using Sinuscones.
Conclusions:
Sinuscones, but not Nozovents, significantly improved PNIF. Repeatability of PNIF measurements was worse with Nozovents and only marginally improved with Sinuscones.
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