Prognostic Indicators of Non-Transection Nerve Injury and Vocal Fold Motion Impairment After Thyroid Surgery – Correlation Between Intraoperative Neuromonitoring Findings and Perioperative Voice Parameters

ObjectivesIn patients with recurrent laryngeal nerve (RLN) injury after thyroid surgery, unrecovered vocal fold motion (VFM) and subjective voice impairment cause extreme distress. For surgeons, treating these poor outcomes is extremely challenging. To enable early treatment of VFM impairment, this study evaluated prognostic indicators of non-transection RLN injury and VFM impairment after thyroid surgery and evaluated correlations between intraoperative neuromonitoring (IONM) findings and perioperative voice parameters.Methods82 adult patients had postoperative VFM impairment after thyroidectomy were enrolled. Demographic characteristics, RLN electromyography (EMG), and RLN injury mechanism were compared. Multi-dimensional voice program, voice range profile and Index of voice and swallowing handicap of thyroidectomy (IVST) were administered during I-preoperative; II-immediate, III-short-term and IV-long-term postoperative periods. The patients were divided into R/U Group according to the VFM was recovered/unrecovered 3 months after surgery. The patients in U Group were divided into U1/U2 Group according to total IVST score change was <4 and ≥4 during period-IV.ResultsCompared to R Group (42 patients), U Group (38 patients) had significantly more patients with EMG >90% decrease in the injured RLN (p<0.001) and thermal injury as the RLN injury mechanism (p=0.002). Voice parameter impairments were more severe in U Group compared to R Group. Compared to U1 group (19 patients), U2 Group (19 patients) had a significantly larger proportion of patients with EMG decrease >90% in the injured RLN (p=0.022) and thermal injury as the RLN injury mechanism (p=0.017). A large pitch range decrease in period-II was a prognostic indicator of a moderate/severe long-term postoperative subjective voice impairment.ConclusionThis study is the first to evaluate correlations between IONM findings and voice outcomes in patients with VFM impairment after thyroid surgery. Thyroid surgeons should make every effort to avoid severe type RLN injury (e.g., thermal injury or injury causing EMG decrease >90%), which raises the risk of unrecovered VFM and moderate/severe long-term postoperative subjective voice impairment. Using objective voice parameters (e.g., pitch range) as prognostic indicators not only enables surgeons to earlier identify patients with low voice satisfaction after surgery, and also enable implementation of interventions sufficiently early to maintain quality of life.

How the Severity and Mechanism of Recurrent Laryngeal Nerve Dysfunction during Monitored Thyroidectomy Impact on Postoperative Voice

Intraoperative neuromonitoring can qualify and quantify RLN function during thyroid surgery. This study investigated how the severity and mechanism of RLN dysfunction during monitored thyroid surgery affected postoperative voice. This retrospective study analyzed 1021 patients that received standardized monitored thyroidectomy. Patients had post-dissection RLN(R2) signal <50%, 50–90% and >90% decrease from pre-dissection RLN(R1) signal were classified into Group A-no/mild, B-moderate, and C-severe RLN dysfunction, respectively. Demographic characteristics, RLN injury mechanisms(mechanical/thermal) and voice analysis parameters were recorded. More patients in the group with higher severity of RLN dysfunction had malignant pathology results (A/B/C = 35%/48%/55%, p = 0.017), received neck dissection (A/B/C = 17%/31%/55%, p < 0.001), had thermal injury (p = 0.006), and had asymmetric vocal fold motion in long-term postoperative periods (A/B/C = 0%/8%/62%, p < 0.001). In postoperative periods, Group C patients had significantly worse voice outcomes in several voice parameters in comparison to Group A/B. Thermal injury was associated with larger voice impairments compared to mechanical injury. This report is the first to discuss the severity and mechanism of RLN dysfunction and postoperative voice in patients who received monitored thyroidectomy. To optimize voice and swallowing outcomes after thyroidectomy, avoiding thermal injury is mandatory, and mechanical injury must be identified early to avoid a more severe dysfunction.

When Inspiratory Stridor Is Not Paradoxical Vocal Fold Motion/Inducible Laryngeal Obstruction: A Case Study of Diaphragm Flutter

Purpose This case study describes the clinical course for an individual referred to a speech-language pathologist (SLP) for assessment and treatment of paradoxical vocal fold motion/inducible laryngeal obstruction (PVFM/ILO) who was ultimately diagnosed with diaphragm flutter. This case presentation describes the critical importance of a multidisciplinary approach to identify conditions in the differential diagnosis of PVFM/ILO, which may lead to timely diagnosis and treatment of such conditions. Method Using a case study format with links to pre- and posttreatment videos, the clinical course of a 20-year-old woman presenting with persistent inspiratory stridor and cough during waking time was delineated. Data used to determine the differential diagnosis included careful clinical observation, extensive medical history, and endoscopic laryngeal assessment. Results Using a multidisciplinary approach with professionals from three different treatment centers, the diagnosis of diaphragm flutter was affirmed and successful medical management with an empiric trial of Baclofen was initiated with complete resolution of the dyspnea, cough, and inspiratory stridor over 3 weeks. Conclusions This case study describes a rare condition in the differential diagnosis of PVFM/ILO called diaphragm flutter, characterized by persistent inspiratory stridor and cough that interrupted connected speech and swallowing. SLPs who specialize in the assessment and treatment of PVFM/ILO may encounter this condition. Clinician awareness of the clinical profile for diaphragm flutter is critical for rapid referral to the appropriate medical specialists to achieve timely symptom relief. Supplemental Material https://doi.org/10.23641/asha.14781867

Visual biofeedback for paradoxical vocal fold motion (PVFM)

Objectives Paradoxical vocal fold motion (PVFM) is a common condition where the vocal folds inappropriately adduct during inspiration. This results in dyspnea and occasionally significant distress. The condition is thought to be primarily functional, with behavioural therapy considered mainstay in the non-acute setting. However, practice variations and limited access to speech language pathology (SLP) services can pose management challenges. We aimed to examine the efficacy of surgeon performed visual biofeedback as first-line treatment for PVFM. Study design Prospective, non-randomized, non-comparative clinical study. Methods Adult patients referred for possible PVFM and congruent laryngoscopy findings over a two-year period were included. Patients were excluded if they presented in acute distress, had alternate diagnosis to explain symptomology and/or coexisting untreated lower respiratory pathology. Patients underwent immediate surgeon-performed visual biofeedback on the same visit day. The primary outcome of interest was change in Dyspnea Index (DI) scores pre- and post-intervention 3 months follow-up. The secondary outcome measured was change in asthma medication use from baseline to follow-up. Results Of 34 patients presenting, 25 met inclusion criteria. Of these, 72% were female with an average age of 36.9 ± 14.1. Approximately 48% of patients had a diagnosis of well-controlled asthma at presentation and co-morbid psychiatric diagnoses were common (52%). Pre- and post-intervention analysis showed significant improvement in DI scores (p < 0.001) and reduction in bronchodilator use (p = 0.003). Conclusion This is a prospective study that evaluates the role of visual biofeedback in PVFM patients. Our data suggests that visual biofeedback effectively reduces short-term subjective symptoms and asthma medication use. Level of evidence 3 Graphical abstract

Vocal Fold Motion Impairment Following Chemotherapy Administration: Case Reports and Review of the Literature

Objective: Chemotherapy-induced vocal fold motion impairment (CIVFMI) is a rare complication of cancer therapy with potential for airway compromise. The objective of this review is to present 2 new cases of CIVFMI to add to the literature as well as characterize the demographics, symptoms, exam findings, airway complication rates and prognosis of CIVFMI. Methods: A search of Pubmed/MEDLINE (1970 to May 1, 2020), Embase (1970 to May 1, 2020), and Cochrane Library using medical study heading (MeSH) terms related to chemotherapy ( drug therapy, chemotherapy, vincristine, vinblastine, paclitaxel) and vocal cord motion impairment ( vocal cord, cords, vocal folds, immobility, hypomobility) was performed. Exploratory pooling of data without formal meta-analysis was performed. Results: A preliminary search yielded 148 abstracts, review articles and studies. A total of 23 studies met inclusion criteria. There were 35 total cases presented in the literature, with a mean age of 29.5 (0.4-78). The most common cancer diagnosis was acute lymphoblastic leukemia (n = 15, 42.9%), and the most common agent was vincristine (n = 30, 85.7%). Dysphagia, bilateral CIVFMI, and vocal fold immobility rather than hypomobility were more common in pediatric patients. There were 8 cases of surgical airway intervention, including tracheostomy and posterior cordotomy. The duration of symptoms was 7 to 420 days, and spontaneous resolution was reported in 32 cases. Conclusions: CIVFMI has potential for airway complications requiring surgical intervention. Spontaneous resolution after cessation of the offending agent is the most likely outcome. Bilateral CIVFMI, dysphagia and vocal fold immobility are more common in the pediatric population.

Paradoxical Vocal Fold Motion Disorder in the Postanesthesia Care Unit

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