To determine the correlation between respiratory resistance (R r ) values measured with the Airflow Perturbation Device (APD) to laryngoscopic images of glottal area (GA) in feigned paradoxical vocal fold motion (PVFM), also known as vocal cord dysfunction.There is a strong inverse relationship between R r and GA such that laryngeal constriction can be detected and quantified by APD-measured R r .Prospective, single subject study.A healthy adult feigned breathing that was characteristic of PVFM. R r and GA were simultaneously recorded, synchronized, and analyzed for three complete breathing cycles with significant glottal constriction occurring during inspiration.Cross-correlation analysis revealed a strong negative correlation (−0.824) between GA and R r during feigned PVFM breathing such that R r increased when GA decreased.APD-measured R r appears to be a viable noninvasive method for diagnostic screening and monitoring of treatment outcomes for individuals presenting with dyspnea related to PVFM.