Transcutaneous laryngeal ultrasonography (TLUS) as an alternative to direct flexible laryngoscopy (DFL) in the perioperative evaluation of the vocal cord mobility in thyroid surgery

Purpose Direct flexible laryngoscopy (DFL) is the golden standard to evaluate the vocal cord (VC) function in thyroid and parathyroid surgery pre- and postoperatively. Transcutaneous laryngeal ultrasonography (TLUS) could represent an alternative to the DFL and has been evaluated in the present study comparing the results of both methods performed at two referral centers for endocrine pathologies. Methods In the setting of a retrospective study, 668 patients (560 female, 118 male; mean age 50.3 ± 14.2) were included from two tertiary referral centers of endocrine surgery. In all patients, TLUS was performed pre- and postoperatively prior to transnasal DFL, which served as a golden standard. TLUS was performed by B-scan (probe 5–13 MHz, aperture 40 mm). Results Preoperative visualization of the vocal cords by TLUS was possible in 526 patients (78.7%). Due to the frequent thyroid cartilage calcification (TCC) in male patients, a significant difference in the visualization rate was found between female and male (88.7% vs. 26.8%) [ p