title: Lessons Learned After 1000 Cases of Transcutaneous Laryngeal Ultrasound (TLUSG) with Laryngoscopic Validation: Is There a Role of TLUSG in Patients Indicated for Laryngoscopic Examination Before Thyroidectomy?
abstract: Patients with hoarseness of voice, previous neck operation, or suspicion of malignancy are at high risk of having pre-thyroidectomy vocal cord (VCP) palsy. Therefore, vocal cord (VC) functions should be evaluated before surgery. This study aimed to evaluate the accuracy of hoarseness, a voice-related questionnaire (Voice Handicap Index [VHI]-30), and transcutaneous laryngeal ultrasound (TLUSG) in diagnosing VCP, as well as the role of TLUSG in the evaluation of high-risk patients.
  
  
  
  A total of 1000 patients undergoing thyroidectomy or other endocrine-related neck procedures were prospectively included. Symptoms of hoarseness, the VHI-30 score, and TLUSG were evaluated. Validation laryngoscopies were performed by a separate endoscopist after performing TLUSG. All the assessments were performed one to seven days before surgery. The findings of hoarseness, the VHI-30 score, and TLUSG were correlated with laryngoscopic findings to evaluate the diagnostic accuracy.
  
  
  
  Of 1000 patients, nine preoperative VCP were diagnosed with laryngoscopy. Sensitivity in detecting VCP by hoarseness, the VHI-30 score, and TLUSG were 33.3%, 62.5%, and 88.9%, respectively. A total of 342 patients were considered as high risk, and eight preoperative VCP were confirmed with laryngoscopy. Despite it not being possible to visualize the VCs in 26 (7.7%) patients, TLUSG had a higher accuracy in detecting VCP than the VHI-30 did (96.8% vs. 74.2%; p < 0.001). If patients had been selected who were unassessable or who had had VCP on assessment for confirmatory laryngoscopy, TLUSG saved more patients from laryngoscopic examinations than the VHI-30 did (87.7% vs. 71.3%; p < 0.001). A history of neck operation and suspicion of malignancy did not affect the assessment by TLUSG (p > 0.05).
  
  
  
  TLUSG is a feasible, non-invasive, and sensitive tool in detecting VCP in high-risk patients. It has safely precluded 87.7% high-risk patients from laryngoscopy. TLUSG should be incorporated as a part of the ultrasound examination of the thyroid.
authors.affiliation: Division of Endocrine Surgery, Department of Surgery, The University of Hong Kong , Queen Mary Hospital, Hong Kong SAR, China .
authors.forename: Kai-Pun
authors.initials: KP
authors.lastname: Wong
authors.affiliation: Division of Endocrine Surgery, Department of Surgery, The University of Hong Kong , Queen Mary Hospital, Hong Kong SAR, China .
authors.forename: Kin-Pan
authors.initials: KP
authors.lastname: Au
authors.affiliation: Division of Endocrine Surgery, Department of Surgery, The University of Hong Kong , Queen Mary Hospital, Hong Kong SAR, China .
authors.forename: Shi
authors.initials: S
authors.lastname: Lam
authors.affiliation: Division of Endocrine Surgery, Department of Surgery, The University of Hong Kong , Queen Mary Hospital, Hong Kong SAR, China .
authors.forename: Brian Hung-Hin
authors.initials: BH
authors.lastname: Lang
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D005260:Female; D006685:Hoarseness / Q000000981:diagnostic imaging* / Q000503:physiopathology / Q000601:surgery; D006801:Humans; D007828:Laryngoscopy; D007830:Larynx / Q000000981:diagnostic imaging* / Q000503:physiopathology; D008297:Male; D008875:Middle Aged; D012680:Sensitivity and Specificity; D013965:Thyroidectomy; D014463:Ultrasonography; D014826:Vocal Cord Paralysis / Q000000981:diagnostic imaging* / Q000503:physiopathology / Q000601:surgery; D055815:Young Adult
keywords: laryngeal ultrasound; preoperative; thyroidectomy; vocal cord palsy