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Updated: Feb 4, 2026

Four-Dimensional Computed Tomography-Guided Valve Sizing for Transcatheter Pulmonary Valve Replacement
Published on: January 20, 2022
The internal nasal valve: a validated grading system and operative guide
B Patel1, J S Virk2, P S Randhawa2
1Rhinology Department, Royal National, Throat, Nose and Ear Hospital, Gray's Inn Road, London, WC1X 8DA, UK. bhavesh.patel7@nhs.net.
Purpose:
Nasal obstruction is a highly subjective and commonly reported symptom. The internal nasal valve (INV) is the rate limiting step to nasal airflow. A static INV grading score was devised with regard to visibility of the middle turbinate.
Methods:
A prospective study of all patients who underwent primary external functional septorhinoplasty in 2017 for nasal obstruction. All patients' INV score was assessed pre- and postoperatively in a blinded and independent fashion by surgeons of varying seniority.
Results:
Twenty-eight patients were studied, with mean age 30.9 years and follow-up 18.8 weeks. Inter-rater and test-retest reliability of INV grading were excellent, with Cronbach's alpha 0.936 and 0.920, respectively. There was also statistically significant improvement in both subjective and objective postoperative outcome measures including nasal inspiratory peak flows.
Conclusions:
We demonstrate a novel, easy to interpret, clinically valuable grading system of the static internal nasal valve that is reliable and reproducible.
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