The Effect of Obesity on Transnasal Flexible Laryngoscopy.

Objective: Transnasal flexible laryngoscopy (TFL) is a practical and cost-effective procedure, allowing excellent evaluation of the upper airway with minimal risk of complications. The effect of obesity on endoscopic examination still remains unclear. The aim of this study was to determine if obesity has an effect on TFL.

Methods: Demographic data including age and gender, and physical and endoscopic examinations including body mass index (BMI), neck circumference, and grade of the laryngeal view according to Tasli classification (TC), Mallampati classification (MC), Friedman classification, and Moore tongue base classification (MTC) scores of 200 patients were evaluated. The patients were divided into two categories as obese and nonobese, and the scores of patients were compared.

Results: Evaluation was made of 99 (50.5%) obese and 97 (49.5%) nonobese patients ranging in age from 18 to 65 years (mean age: 37.89 ± 13.55 years). Of the 196 patients in this study, 101 (51.5%) were male, and 95 (48.5%) were female. The mean BMI of the obese and nonobese patients was 33.18 ± 5.18 (min: 25, max: 45) and 22.48 ± 1.5 (min: 19, max: 24), respectively. According to cutoff points, 27 patients (27.3%) were classified as overweight, 30 (30.3%) as obese, and 42 (42.4%) as morbidly obese. According to TC, there was no statistically significant difference between the obese and nonobese groups (mean difference 0.12, P: 0.39). In Pearson correlation analysis, the scores for a correlation between TC, and MC and MTC were 0.206 (very weak) and 0.653 (strong), respectively, which were statistically significant (P < 0.05). There was no correlation between TC and BMI values (r = -0.051; P: 0.48).

Conclusion: The results of this study demonstrated that obesity influences the scores of MC, Friedman classification, and MTC, but does not affect the laryngeal view on TFL.