Flexible Versus Rigid Laryngoscopy: A Prospective, Blinded Comparison of Image Quality

Endoscopic Distance and its Impact on Quantified Age-related Vocal Fold Atrophy Measures

INTRODUCTION

The bowing index (BI) and normalized glottal gap area (NGGA) are used to quantify vocal fold morphology in ARVA; however, the influence of the distance between the flexible laryngoscope lens and the target area is not known. The goal is to test whether the endoscopic distance impacts vocal fold morphology measurements in patients with ARVA during flexible video laryngostroboscopy (VLS).

METHOD

Patients with ARVA who underwent VLS were included. Images were classified into near (close to the petiole of the epiglottis) and far (below nasopharynx, with tongue base and entire epiglottis visible) conditions. BI was calculated using a mobile application, and NGGA was measured using ImageJ.

RESULTS

This study included 23 patients; the mean age was 77 ± 7 years. Mean BI measured at the near distance was higher than far distances with a mean difference of 1.94 (95% CI: 0.92-2.96, p = 0.001). NGGA showed difference with changed distance -0.24 (95% CI: -0.48 to 0.01, p < 0.05).When stratifying patients into two groups based on median BI measurement, there was a statistically significant difference between near and far conditions, with increased BI in the near condition for patients above the median (p < 0.05), but no difference between the near and far condition for patients with BI below the median.

CONCLUSION

The BI and NGGA were impacted by the endoscopic distance during flexible VLS. BI was significantly higher in the near condition compared with the far condition. The difference in BI between the near and far conditions was more pronounced when the vocal fold bowing was greater. These findings call for heightened awareness of measurement discrepancies secondary to the endoscopic distance during flexible laryngostroboscopy.

LEVEL OF EVIDENCE

Level 2 Laryngoscope, 2024.

Immediate and Short-term Effects of Straw Phonation in Air or Water on Vocal Fold Vibration and Supraglottic Activity of Adult Patients with Voice Disorders Visualized with Strobovideolaryngoscopy: A Pilot Study

Purpose The first purpose of this study was to investigate and compare the short-term effects after a semi-occluded vocal tract (SOVT) therapy session consisting of straw phonation (SP) in air or water on vocal fold vibration and supraglottic activity of adult patients with voice disorders, visualized with strobovideolaryngoscopy (SVL). The second purpose of this study was to investigate and compare immediate changes in the patients' vocal fold vibration and supraglottic activity during SP in air or water, visualized with SVL. Methods Twelve adult patients with voice disorders (eight women and four men, mean age 52 years) were assigned randomly to one of two study groups: SP in air or SP in water. Immediately before and after a therapy session of 15 min, participants underwent a rigid SVL to determine the short-term effects of the SP session. At the posttherapy examination, flexible SVL while performing SP was added to determine the effects occurring during SP. The visual-perceptual ratings were performed blindly and in random order by three laryngologists, using the Voice-Vibratory Assessment with Laryngeal Imaging rating form for stroboscopy. ResultsShort-term effects after SP: After the SP-in-air session, the supraglottic mediolateral compression decreased significantly. The SP-in-water session led to significantly increased left vibrational amplitude. Immediate effects during SP: During SP in air, a significantly increased left amplitude and mucosal wave, and significantly decreased mediolateral supraglottic activity, were found. SP in water tended to decrease the vibrational amplitude during performance of the task. A trend toward higher anteroposterior supraglottic compression was observed during both SP in air and water, being more prominent in the latter. Conclusion SP in air led to less false vocal fold adduction and consequently less hyperfunction. The small increment in anteroposterior supraglottic activity during SP in air and water might be related to epilarynx narrowing, an economic phenomenon associated with SOVT exercises. The effects on vibrational amplitude were rather ambiguous. The small reduction in amplitude during SP in water is expected to diminish vocal fold impact stress and therefore creates an ideal basis for voice therapy. The increment in amplitude and mucosal wave during SP in air might indicate insufficient supraglottic pressure to obtain the favorable effects of semi-occlusion. Whether or not the rise in amplitude after the SP-in-water session is due to voice efficiency or voice fatigue remains unknown. Future larger-scale investigation in subgroups of voice patients is needed to explore these hypotheses.

Adenoid measurement accuracy: A comparison of lateral skull film, flexible endoscopy, and intraoperative rigid endoscopy (gold standard)

OBJECTIVE

To compare the accuracy of lateral skull film, flexible endoscopy, and intraoperative rigid endoscopy in assessment of adenoid size.

METHODS

A cross-sectional study was conducted in 43 pediatric patients undergoing ENT surgery from July 2017 to December 2018. All patients underwent preoperative lateral skull film, flexible endoscopy, and intraoperative rigid endoscopy.

RESULTS

The average adenoidal-nasopharyngeal (A/N) ratio obtained from lateral skull film, flexible endoscopy, and intraoperative rigid endoscopy was 72.9, 79.5, and 81.6, respectively. There was a moderate correlation between A/N ratio from lateral skull film and intraoperative rigid endoscopy (Pearson's correlation: 0.567, p˂0.001). Whereas, the A/N ratio from flexible endoscopy compared to intraoperative rigid endoscopy showed a stronger correlation (Pearson's correlation: 0.791, p˂0.001). From linear regression analysis, the intraoperative adenoid measurement was estimated from the results of flexible endoscopy (intraoperative rigid endoscopy: 0.72 [flexible endoscopy] +24.47) and lateral skull film (intraoperative rigid endoscopy = 0.65 [lateral skull film] + 34) CONCLUSION: Flexible endoscopy yields the most accuracy in the assessment of adenoid size and nasopharynx visualization, without radiation exposure or anesthesia. Despite less accuracy, lateral skull film is more availability in every hospital. The correlation of adenoid size measurement in this study can also be applied for the actual size of adenoid.