Vocal Cord Palsies Missed by Transcutaneous Laryngeal Ultrasound (TLUSG): Do They Experience Worse Outcomes?

Abstract

Introduction Transcutaneous laryngeal ultrasound (TLUSG) is an innovative, non‐invasive tool in detecting post‐thyroidectomy vocal cord palsy (VCP). However, TLUSG failed to detect about 6–15% laryngoscopic examination (LE)‐confirmed VCP. It is unclear whether the outcome of patients with VCP missed by TLUSG [false negative (FN)] is different from those with VCP diagnosed by TLUSG [true positive (TP)]. Therefore, this study aimed to compare the clinical outcome and prognosis between patients with FN results and TP results. Methods Over 46 months, all consecutive patients undergoing thyroidectomy or endocrine‐related neck procedure were recruited. They underwent pre‐operative and post‐operative voice assessments on symptoms, voice‐specific questionnaire [voice handicap index questionnaire (VHI‐30)], TLUSG and LE. For patients with post‐operative vocal cord palsy, reassessment LE would be arranged at second, fourth, sixth and twelfth months post‐operatively until VCP recovered. Results In total, 1196 patients, including 74 post‐thyroidectomy VCP, were recruited. For those with assessable vocal cords (VC), 58 VCP were correctly diagnosed by TLUSG (TP) and 10 VCP were missed by TLUSG (FN). Sensitivity and specificity of detecting a VCP by TLUSG were 85.3% and 94.7%, respectively. VHI‐30 score was significantly increased after operation in TP group [31 (range − 6–105), p < 0.001] but not in FN group [20 (14–99), p = 0.089]. Comparing to TP group, VCP recovered earlier (69 vs. 125 days, p < 0.001) and less patients suffered from permanent VCP in patients with FN results. (34.5% vs. 0.0%, p = 0.027). Conclusion The VCP missed by TLUSG had a milder course of disease. Early recovery of VC function and non‐permanent palsy were expected.

Utility of ultrasound in the assessment of swallowing and laryngeal function: A rapid review and critical appraisal of the literature

“…2014), thyroid surgery plus other endocrine‐related neck procedures ( n = 1) (Wong et al . 2019) or other neck operations ( n = 1) (Woo et al . 2017).…”

“…2019, Wong et al . 2014, 2019), handheld ( n = 1) (Miura et al . 2020), self‐made ( n = 1) (Chen et al .…”

“…PPV for US assessment ranged from 47.9% (Wong et al . 2019) to 100% (Fung and Lang 2020). NPV for US assessment ranged from 22% (de Miguel et al .…”

“…In the six studies, NPV was higher than PPV in three studies (Wong et al . 2019, Shah et al . 2019, Gambardella et al .…”

“…Patient population across the 10 swallowing studies included stroke (n = 2) (Kim et al 2012, Picelli et al 2020, motor neuron disease (n = 1) (Tamburrini et al 2010), post-radiotherapy (n = 1) (Cheng et al 2018) and mixed inpatient cohorts (n = 6) (Chen et al 2017, Manabe et al 2018, Lee et al 2016, Miura et al 2014, 2020. In the 13 laryngeal studies, nine included populations undergoing thyroid surgery (n = 7) (Dubey et al 2019, Shah et al 2019, Kumar et al 2018, de Miguel et al 2017, Kandil et al 2016, Gambardella et al 2020, Wong et al 2014, thyroid surgery plus other endocrine-related neck procedures (n = 1) (Wong et al 2019) or other neck operations (n = 1) (Woo et al 2017). The four remaining studies included participants undergoing neck surgery presenting risk to the recurrent laryngeal nerve (n = 2) (Carneiro-Pla et al 2014, Fung and Lang 2020), a mixed neck and vocal fold population (n = 1) (Amis et al 2012) and patients undergoing anterior-cervical (AC) spinal surgery (n = 1) (Kamel et al 2020).…”