Pre- and post-operative high-speed videolaryngoscopy in unilateral vocal cord paralysis following autologous fat...

To compare high-speed videolaryngoscopy (HSV) parameters such as open quotient (OQ), amplitude symmetry index (ASI), phase symmetry index (PSI), and frequency symmetry index (FSI), of the unilateral vocal cord paralysis (UVCP) patients pre and post (after 6 months) autologous fat augmentation.

This retrospective study evaluated all age and gender patients with UVCP that underwent autologous fat augmentation from July 2016 to July 2019. The OQ, ASI, PSI, and FSI were calculated from the HSV recordings by using the montage and fast Fourier transform point analysis. The pre-and post-operative means were compared using a paired student t-test, with a p-value less than 0.05 considered significant.

A total of 37 patients, age 41.2 ± 11.3 years (21 to 67 years), 59.4% females and 40.6% males, were included in the study. The average duration of symptom onset was 2.3 ± 0.87 months. The post-operative mean values of OQ, ASI, PSI, and FSI following the fat augmentation were significantly improved compared to the pre-operative mean values with p-values <0.0001, 0.0018, 0.0011, and 0.0006, respectively.

There was a significant improvement in the OQ, ASI, PSI, and FSI in UVCP patients after 6 months of autologous fat augmentation, signifying an enhanced vibratory function. The ability of HSV to measure the minute details of vocal cord vibration by providing quantitative measurements has also been highlighted. The need for future prospective research with an increased sample size and longer duration of follow up is recommended.