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Updated: Sep 6, 2026

Employing the Forced Oscillation Technique for the Assessment of Respiratory Mechanics in Adults
Published on: February 9, 2022
Spirometric indices in the assessment of laryngeal obstruction
Abstract:
To determine if spirometric indices allow detection and quantification of a laryngeal obstruction, we obtained oro-laryngeal airway resistance (Ro1) and several spirometric indices in 43 patients with various laryngeal diseases. Assuming Ro1 greater than or equal to 0.2 kPa/(1/s) to imply a laryngeal obstruction, the highest sensitivity was found for FIV1 = 2.0 1 (forced inspiratory volume in one second) being about 84% at a specificity of about 88%. The highest correlation coefficients (r = 0.72-0.83) were obtained between Ro1 and MIF50/MEF50 (the ratio between maximum expiratory and inspiratory flow at 50% of vital capacity) and between I/Ro1, and PIF (peak inspiratory flow), MIF50 and FIV1. In conclusion spirometric indices allow detection of a laryngeal obstruction in the majority of cases, but do not appear adequate for a quantitative assessment in an individual patient.
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