Accuracy of a Laryngopharyngeal Endoscopic Esthesiometer (LPEER) for Evaluating Laryngopharyngeal Mechanosensitivity: A Validation Study in a Prospectively Recruited Cohort of Patients

Abstract

Recent studies have shown an association between alterations in laryngopharyngeal mechanosensitivity (LPMS) and dysphagia, obstructive sleep apnea, and chronic cough hypersensitivity syndrome. A previous reliability study of a new laryngopharyngeal endoscopic esthesiometer and rangefinder (LPEER) showed high intra- and inter-rater reliability; however, its accuracy has not been tested. We performed an accuracy study of the LPEER in a prospectively and consecutively recruited cohort of 118 patients at two tertiary care university hospitals. Most of the patients were suffering from dysphagia, and all of them underwent a standard clinical evaluation and fiberoptic endoscopic evaluation of swallowing with sensory testing (FEESST) using a new sensory testing protocol. The sensory test included determinations of the laryngeal adductor reflex threshold (LART), the cough reflex threshold (CRT) and the gag reflex threshold (GRT). Abnormalities on these reflex thresholds were evaluated for associations with major alterations in swallowing safety (pharyngeal residues, penetration, and aspiration). We evaluated the discriminative capacity of the LPMS test using ROC curves and the area under the curve (AUC-ROC) and its relationship with the eight-point penetration-aspiration scale (PAS) using the Spearman's ρ correlation coefficient (SCC). We found a positive correlation between the PAS and LART (SCC 0.47; P < 0.001), CRT (SCC 0.46; P < 0.001) and GRT (SCC 0.34; P = 0.002). The AUC-ROC values for detecting a PAS ≥7 were as follows: LART, 0.83 (P < 0.0001); CRT, 0.79 (P < 0.0001); GRT, 0.72 (P < 0.0001). In this study, the LPEER showed good accuracy for evaluating LPMS. These results justify further validation studies in independent populations.

Inter- and Intra-Rater Reliability of Laryngeal Sensation Testing with the Touch Method During Flexible Endoscopic Evaluations of Swallowing

“…However, there are some limitations with the air pulse method, including device generated noise, poor stimulus reproducibility, limited stimulus range, and a lack of commercially manufactured equipment. 43 Though equipment has since been developed to address these limitations, [44][45][46] a major benefit of the touch method is that it can be performed during routine FEES exams and does not require specialized equipment. Few studies have directly compared the air pulse and touch methods.…”

Evaluation methods and influencing factors of cough sensitivity

“… 81 The high intra- and inter-rater reliability and accuracy of LPEER for evaluating laryngopharyngeal sensitivity have been proved. 82 , 83 Studies have shown that in patients with laryngeal irritation, the LART is slightly increased and the CRT and GRT are decreased. 81 At present, studies are focused on the application of this device in the evaluation of laryngopharyngeal sensitivity in patients with difficult swallowing, while no related studies have been conducted in patients with chronic cough.…”

“…Giraldo-Cadavid et al [81][82][83] designed and developed a novel laryngopharyngeal endoscopic esthesiometer and rangefinder (LPEER) composed of a high precision air pulse generator, an endoscopic laser rangefinder. The device uses endoscopic air pulses to generate pressure on the mucosa of the laryngopharyngeal tube; increasing pulse intensity triggers the laryngeal adductor reflex, cough reflex, and gag reflex.…”