Laryngeal sensory neuropathy caused by COVID-19: findings using laryngeal electromyography.

PURPOSE: Laryngeal sensory neuropathy (LSN) is caused by a disorder of the superior laryngeal nerve or the recurrent laryngeal nerve. A diagnosis of LSN should include laryngeal electromyography (LEMG) and laryngovideostroboscopy (LVS). The aim of this study was to characterize the physical and subjective symptoms of neuropathy in patients diagnosed with LSN following COVID-19. MATERIAL AND METHODS: Since the beginning of the COVID-19 pandemic, 6 patients who had recovered from the disease presented to us with LSN symptoms. All patients underwent laryngological and phoniatric examination, objective and subjective voice assessment, and LEMG. RESULTS: The most common LSN symptom reported by patients was periodic hoarseness of varying severity. Other common symptoms were the sensation of a foreign body in the throat and voice fatigue. Endoscopy often showed functional abnormalities. The LSN patients could be characterized by LEMG recordings, and all showed abnormal activity of the cricothyroid (CT) muscle. The degree of EMG changes in the CT correlated moderately with the severity of dysphonia. CONCLUSIONS: Sensory neuropathy of the larynx may be a long-lasting complication of SARS-COV-2 infection. The severity of EMG neuropathic changes in the CT muscle broadly corresponds to the severity of dysphonia.

Electromyography of the posterior cricoarytenoid muscles: a consensus guideline.

PURPOSE: Since the introduction of transcutaneous-transcricoidal needle approaches, electromyography (EMG) of the posterior cricoarytenoid muscle (PCA) became easier to perform and teach. Among the Neurolaryngology working group of the European Laryngological Society, several centers have adopted PCA EMG as part of their routine EMG workup in vocal fold immobility collectively gathering long-term experience. The purpose is to give an update and an extension to already existing guidelines on laryngeal EMG with specific regard to PCA EMG. METHODS: Consensus of all co-authors is based on continuous exchange of ideas and on joint laryngeal EMG workshop experiences over at least 7 years. A Delphi method of consensus development was used, i.e., the manuscript was circulated among the co-authors until full agreement was achieved. RESULTS: Step-by-step instructions on how to perform and interpret PCA EMG are provided. CONCLUSIONS: Further research should include the establishment of normal values for PCA and thyroarytenoid muscle (TA) EMG as well as studies on the nature of some unusual activation pattern commonly seen in chronically lesioned PCA.

Vocal fold injection material does not preclude interpretation of laryngeal electromyography.

INTRODUCTION/AIMS: Temporary vocal fold injection (VFI) is a common treatment for acute and subacute vocal fold paralysis (VFP). Laryngeal electromyography (LEMG) is useful for diagnosing neurogenic causes of VFP. This study evaluated whether the presence of VFI material prevents interpretation of LEMG in patients with acute and subacute VFP. METHODS: Patients with acute and subacute unilateral VFP (onset ≤6 mo) who underwent temporary VFI within 3 mo preceding LEMG were evaluated. A matched control group that did not undergo VFI was also studied. The LEMG team (laryngologist and electromyographer) performed and interpreted LEMG using a pre-specified protocol, including qualitative and quantitative motor unit analysis. RESULTS: Eighteen patients with VFI underwent LEMG successfully with interpretation of spontaneous activity and motor unit recruitment. Fourteen patients were seen in follow-up to determine accuracy of established LEMG prognosis. Seven of seven subjects with poor LEMG prognosis did not recover vocal fold motion. Five of seven subjects with fair LEMG prognosis recovered vocal fold motion. Findings were similar for the control group. DISCUSSION: VFI augmentation material did not prevent interpretation of meaningful LEMG data in patients with acute and subacute VFP, and accurate prognoses of vocal fold motion recovery were established.

Quantitative laryngeal electromyography parameters may correlate with improved outcomes following botulinum toxin injection for spasmodic dysphonia.

BACKGROUND: Despite use of qualitative laryngeal electromyography (LEMG) guided botulinum toxin A (BoNT-A) injection for treatment of adductor spasmodic dysphonia (AdSD), unsatisfactory injections and complete "misses" remain problematic. We aimed to determine if the quantitative LEMG measure of number of small segments (NSS) correlates with voice outcomes following (BoNT-A injection for AdSD. METHODS: Automated quantitative LEMG analysis was performed during electromyography (EMG) -guided BoNT-A injection into the thyroarytenoid-lateral cricoarytenoid muscle complex for treatment of AdSD. Pre-injection phonatory NSS values were correlated with clinical voice outcomes and patient reported injection results. RESULTS: Quantitative LEMG measures were obtained for 45 AdSD patients (28 female, mean age 60.8 ± 12.8 years) during EMG-guided BoNT-A injection. Mean sampled NSS during phonation immediately prior to BoNT-A injection was 524 ± 323 (range: 2-904). Mean follow up was 36.5 ± 9.4 days; one patient was lost to follow-up. In comparison to their previous BoNT-A injection, the current injection was rated as worse, same, and better by 13 (29.5%), 25 (56.8%), and 6 (13.6%) patients, respectively. All 4 (9.1%) patients with NSS < 200 rated their BoNT-A injection result as worse than previous, and change in Voice Handicap Index-10 (VHI-10) scores were worse or without change. CONCLUSIONS: Aiming for an NSS value greater than 200 during phonation prior to BoNT-A toxin injection for AdSD may reduce unfavorable voice outcomes.

Objectivation of laryngeal electromyography (LEMG) data: turn number vs. qualitative analysis.

PURPOSE: This paper describes a first attempt to quantify LEMG data based on turn number calculation. The results obtained for both healthy and ailing thyroarytenoid (TA) muscles of patients with unilateral vocal fold immobility (UVFI) were compared with the respective qualitative evaluation concerning volitional activity to determine whether the two types of analyses deliver similar results. METHODS: LEMG data obtained from 44 adults with UVFI were considered for the study. Semiquantitative evaluation of TA volitional activity and turn number were assessed for the ailing and the healthy TA and the difference in percentage was calculated. Paired data were compared with the Wilcoxon signed-rank test. The volitional activity assessment and the turn number evaluation were compared with the Kruskal-Wallis test, and their relationship was tested with the Kendall rank correlation. RESULTS: Datasets of 27 patients were considered compatible with turns/s calculation. The results showed that complete paralysis correlated with no turns; single fiber volitional activity with 62-208 turns/s, strongly decreased volitional activity with 198-501 turns/s; and dense volitional activity with 441-1234 turns/s. On the ailing VF only, the Kruskal-Wallis test showed a statistically significant difference (p = 0.0001), and the Kendall rank correlation a positive relationship (r = 0.853,p ≤ 0.0001) between the volitional activity rating and the turn number assessment. CONCLUSIONS: Our preliminary results showed that turn number evaluation is an effective tool to confirm LEMG qualitative analysis, and that, in combination with laryngostroboscopy and voice assessment, can help improving the accuracy of the diagnosis and prognosis and the effectiveness of the chosen therapy.

Current management of arytenoid sub-luxation and dislocation.

PURPOSE: To review the current management of arytenoid subluxation/dislocation (AS/AD) focusing on diagnostic, therapeutic, and prognostic controversies. METHODS: The international literature of the last 20 years has been considered. After the application of inclusion criteria, 20 studies were selected (471 AS/AD cases in total). RESULTS: All the included investigations were retrospective case series. AS/AD was often iatrogenic occurring at least in 0.01% of patients undergone endo-tracheal intubation. The most common symptom was persistent hoarseness. The diagnosis was made by video-laryngoscopy and neck computed tomography in most reports, while some used also laryngeal electromyography. Laryngeal electromyography was fundamental to rule out unilateral vocal fold paralysis, the main differential diagnosis. The surgical relocation of AS/AD under general or local anesthesia was achieved in about 80% of patients. CONCLUSION: AS/AD is a mechanical disorder of the larynx that can be successfully treated if promptly diagnosed. Clinical trials and multi-centric studies are necessary to set management guidelines.

Ultrasonography-guided electromagnetic needle tracking in laryngeal electromyography.

PURPOSE: The clinical evaluation of vocal fold movement disorders should contain the electromyography of the laryngeal muscles (LEMG). The most challenging point in LEMG is the right positioning of the EMG needle in the small target muscles. As the results of the EMG have great influence in the decision of treatment it is important to confirm the results of this examination. Anatomical structures of the larynx should be identified with laryngeal ultrasonography and the ultrasonography (US)-guided electromagnetic needle tracking should guide the LEMG needle to the target muscle. METHODS: The thyroarytenoid (TA) and cricothyroid (CT) muscles had been evaluated in 19 patients (20 examinations). The US-guided transcutaneous LEMG using electromagnetic needle tracking was performed by one ENT doctor and all examinations had been video monitored. The videos were analyzed for the accuracy rate and the visibility of the important laryngeal structures. RESULTS: The laryngeal structures were identified in all the cases using laryngeal ultrasonography. The examination times of the US-guided LEMG were acceptable (8 min, 32 s). The US-guided LEMG was feasible in 56 (36 TA, 20 CT) examinations. The TA and CT could be visualized successfully but in 17 examinations (30%) the signal was not stable. We could still reach the target muscles in more than 50% of these cases. CONCLUSION: US-guided electromagnetic needle tracking in LEMG helps to determine the exact position of the laryngeal structures. With further technical improvement of the stability of the electromagnetic needle tracking signal the US-guided electromagnetic needle tracking of the target muscles in the larynx could help to improve the accuracy of the transcutaneous LEMG.

Inter-rater reliability of seven neurolaryngologists in laryngeal EMG signal interpretation.

PURPOSE: Laryngeal electromyography (LEMG) has been considered as gold standard in diagnostics of vocal fold movement impairment, but is still not commonly implemented in clinical routine. Since the signal interpretation of LEMG signals (LEMGs) is often a subjective and semi-quantitative matter, the goal of this study was to evaluate the inter-rater reliability of neurolaryngologists on LEMGs of volitional muscle activity. METHODS: For this study, 52 representative LEMGs of 371 LEMG datasets were selected from a multicenter registry for a blinded evaluation by 7 experienced members of the neurolaryngology working group of the European Laryngological Society (ELS). For the measurement of the observer agreement between two raters, Cohen's Kappa statistic was calculated. For the interpretation of agreements of diagnoses among the seven examiners, we used the Fleiss' Kappa statistic. RESULT: When focusing on the categories "no activity", "single fiber pattern", and "strongly decreased recruitment pattern", the inter-rater agreement varied from Cohen's Kappa values between 0.48 and 0.84, indicating moderate to near-perfect agreement between the rater pairs. Calculating with Fleiss' Kappa, a value of 0.61 showed good agreement among the seven raters. For the rating categories, the Fleiss' Kappa value ranged from 0.52 to 0.74, which also showed a good agreement. CONCLUSION: A good inter-rater agreement between the participating neurolaryngologists was achieved in the interpretation of LEMGs. More instructional courses should be offered to broadly implement LEMG as a reliable diagnostic tool in evaluating vocal fold movement disorders in clinical routine and to develop future algorithms for therapy and computer-assisted examination.

Voice aerodynamics following office-based hyaluronate injection laryngoplasty.

OBJECTIVES: Neuromuscular control, glottal conformation and aerodynamics are the major factors affecting voice performance. We aimed to characterise the degree to which voice improvements following office-based intracordal hyaluronate injection laryngoplasty (HIL) depend on changes in voice aerodynamics in patients with unilateral vocal fold paralysis (UVFP), by assessing the correlations between these parameters. DESIGN: Prospective case series. SETTING: Otolaryngology Clinics in a Medical Center. PARTICIPANTS: Patients with UVFP within 6 months of their first outpatient visit who received single HIL. MAIN OUTCOME MEASURES: Videolaryngostroboscopy, aerodynamics and laboratory voice analysis were evaluated at baseline and 1 month after HIL. Quantitative laryngeal electromyography was evaluated at baseline to confirm UVFP. RESULTS: Seventy-five newly diagnosed patients with UVFP were analysed. The normalised glottal gap area (NGGA) decreased (P < 0.001) (Cohen's dz  = 0.94) and all aerodynamic parameters improved (all P < 0.05) (Cohen's dz  = 0.38-1.02) following HIL. Patients undergoing thoracic surgery had more profound aerodynamic impairments both before and after HIL. After adjusting for improvements in NGGA, the improvement in aerodynamics was correlated with voice improvement and most notably with maximum phonation time and jitter/shimmer. CONCLUSIONS: Hyaluronate injection laryngoplasty improved glottal conformation, aerodynamics and voice, highlighting the benefit of early HIL intervention for patients with UVFP. Patients with UVFP caused by thoracic surgery continued to have poorer aerodynamics post-HIL, indicating the importance of speech therapy in these patients.

Bilateral vocal cord immobility resulting from cytomegalovirus pharyngitis: A case report.

Human cytomegalovirus (CMV) is an infectious herpes virus present in approximately 50% of the world's population. Pharyngitis is an uncommon manifestation of CMV infection, and vocal cord immobility (VCI) following CMV pharyngitis is quite rare. An 83-year-old man with well-controlled diabetes mellitus and hypertension was admitted due to dyspnea, odynophagia, and dysphagia. Laryngeal fiberscopy revealed bilateral vocal cords almost fixed at the median position, with mucosal redness, swelling, and edema at the hypopharyngeal area. The airway was so narrowed that an emergency tracheostomy was performed to secure an airway. VCI resulting from a malignant tumor was suspected at first, but repeated pathological examinations revealed CMV infection in the pharyngeal mucosa. Despite intravenous ganciclovir treatment (5 mg/kg), the patient's bilateral VCI improved only slightly. Laryngeal electromyography was used to investigate the causes of VCI, and revealed vocal fold paralysis on the left side and cricoarytenoid joint fixation on the right side. This case highlights the importance of considering CMV infection in the differential diagnosis of patients with pharyngitis and VCI. To the best of our knowledge, this is the first case report describing the etiology of VCI following CMV pharyngitis using laryngeal electromyography.

Vocal fold paresis: Medical specialists' opinions on standard diagnostics and laryngeal findings.

PURPOSE: There is still no clear consensus on the diagnostic value of specific laryngeal findings in patients with suspected vocal fold paresis (VFP). The aim of the study was to establish expert opinion on criteria for the diagnosis of VFP in Europe. METHODS: A cross-sectional survey using the questionnaire introduced by Wu and Sulica for US American experts was addressed to laryngeal experts in Germany, Austria, and Switzerland and in a second survey wave to members of the European Laryngological Society. RESULTS: 100 respondents returned survey 1 (response rate 47.2%). 26% worked at a university department. 28% regularly used laryngeal electromyography (LEMG). A pathologic test results in LEMG was considered to have the strongest positive predictive value for VFP (79 ± 23%), followed by a decreased vocal fold abduction (70 ± 29%), decreased vocal fold adduction (61 ± 34%), and atrophy of the hemilarynx (61 ± 31%). The multivariate analysis showed the predictive value of LEMG was estimated lower by respondents from non-university hospital (ß = - 16.33; confidence interval (CI) = - 25.63 to - 7.02; p = 0.001) and higher in hospitals with higher frequency of VFP patients per months (ß = 1.57; CI = - 0.98 to 2.16; p < 0.0001). 30 ELS members returned survey 2 (response rate, 8.4%). Their answers were not significantly different to survey 1. CONCLUSIONS: The laryngology experts in Europe rely on LEMG for diagnosis of VFP like the US American experts, but paradoxically only a minority uses LEMG frequently. Next to LEMG, motion abnormities were considered to have the best predictive value for the diagnosis of VFP.

[The role of laryngeal electromyography in the diagnosis of vocal cord movement disorders]. / A laryngealis electromyographia szerepe a hangszalag-mozgászavarok diagnosztikájában és az alkalmazott kezelés kiválasztásában.

The development of the therapeutic possibilities of vocal cord immobility necessitated the parallel renewal of diagnostic methods. In the last years, laryngeal electromyography, which was first introduced more than 70 years ago, has been re-discovered. After reviewing the international literature and their own experience, the authors present the indications, technical requirements, method and, particularly, the evaluation of the results of this procedure. Laryngeal electromyography makes the differentiation between mechanical fixation and immobility with neurological origin of the vocal folds possible. In case of laryngeal paralysis/paresis it also evaluates objectively the severity of neural injury, the prognosis of the disease and the necessity of any glottis-widening procedure. The widespread application of dynamic rehabilitation interventions is not conceivable without the routine application of laryngeal electromyography, so this sensitive diagnostic tool has to be introduced in all laryngological centers. Orv Hetil. 2018; 159(8): 303-311.

Laryngeal electromyographic changes in postthyroidectomy patients with normal vocal cord mobility.

Thyroidectomy has been used for the treatment of thyroid disease for more than 100 years. In spite of the advancement of surgical techniques, there is still a risk of laryngeal nerve injury. The risk of partial or complete injury still depends on some surgical and disease-related factors. The aim of this study is to show the partial injury and to establish these risk factors via laryngeal electromyographic analysis (LEMG) in postthyroidectomy patients with normal vocal cord motion and mucosal anatomy. Patients who had undergone thyroid surgery were enrolled in this prospective study. LEMG analysis was performed to all patients with normal vocal cord mobility preoperatively and was repeated after the first and the third months of surgery. Thyroarytenoid (TA) and cricothyroid (CT) muscles were used to evaluate recurrent and external branch of superior laryngeal nerves, respectively. Four of the 32 patients had mild-to-moderate degrees of partial LEMG changes during preoperative LEMG analysis of TA and CT muscles on each side. After 3 months of surgery, there was a statistically significant worsening of LEMG findings in the right and left external branches of superior and left recurrent laryngeal nerves. Disease and surgery-related risk factors were analyzed. However, there was no significant relationship on the progression of LEMG findings according to these parameters. This is the first prospective study which supports the risk of progression of LEMG changes in patients with normal laryngoscopic examination after thyroid surgery. No reliable significant risk factor was found influencing the LEMG progression.

Consensus statement: Using laryngeal electromyography for the diagnosis and treatment of vocal cord paralysis.

INTRODUCTION: The purpose of this study was to develop an evidence-based consensus statement regarding use of laryngeal electromyography (LEMG) for diagnosis and treatment of vocal fold paralysis after recurrent laryngeal neuropathy (RLN). METHODS: Two questions regarding LEMG were analyzed: (1) Does LEMG predict recovery in patients with acute unilateral or bilateral vocal fold paralysis? (2) Do LEMG findings change clinical management in these individuals? A systematic review was performed using American Academy of Neurology criteria for rating of diagnostic accuracy. RESULTS: Active voluntary motor unit potential recruitment and presence of polyphasic motor unit potentials within the first 6 months after lesion onset predicted recovery. Positive sharp waves and/or fibrillation potentials did not predict outcome. The presence of electrical synkinesis may decrease the likelihood of recovery, based on 1 published study. LEMG altered clinical management by changing the initial diagnosis from RLN in 48% of cases. Cricoarytenoid fixation and superior laryngeal neuropathy were the most common other diagnoses observed. CONCLUSIONS: If prognostic information is required in a patient with vocal fold paralysis that is more than 4 weeks and less than 6 months in duration, then LEMG should be performed. LEMG may be performed to clarify treatment decisions for vocal fold immobility that is presumed to be caused by RLN. Muscle Nerve 53: 850-855, 2016.

Diagnosis and management of unilateral thyroarytenoid muscle palsy.

The objective of this study is to assess and propose a method of diagnosis and management of patients with unilateral thyroarytenoid muscle palsy (TAMP). This is a retrospective review of clinical records. The records of seven patients diagnosed as having idiopathic TAMP were reviewed. Despite the adductive and abductive functions of the vocal folds being within normal range, apparent palsy was seen in the unilateral thyroarytenoid muscle of these patients. TAMP was confirmed by laryngeal electromyography, and the adductive and abductive movements of the vocal folds were evaluated as the mobility of the arytenoid cartilages by three-dimensional computed tomography and endoscopy. Most of patients with TAMP had been diagnosed as having other diseases or normal, and in one patient, it took over 6 years to establish a correct diagnosis. Two patients recovered by conservative treatment; however, in five patients, TAMP remained even after 6 months. In 4 of those 5 patients, treatment with hyaluronic acid injections was performed. In the remaining patient, surgical treatment, namely, nerve-muscle pedicle flap implantation was performed, which resulted in a favorable recovery of phonation. The average maximum phonation time (MPT) of all patients was extended from 11.4 (±4.4) s before treatment to 19.9 (±4.3) s after treatment, and the pitch range was also increased from 25.1 (±7.2) to 34.6 (±5.8) semitones following our management course. Our results indicate that there is a possibility that TAMP can be diagnosed and treated sufficiently. Therefore, further research toward establishing the concept of and treatment for TAMP is anticipated.

Laryngeal Electromyography is Helpful for Cardiovocal Syndrome.

Laryngeal electromyography is used in the evaluation of vocal cord paralysis to confirm the diagnosis, to guide the diagnostic work-up for etiology, to provide prognostic information and to help choose the correct treatment for the patient. Cardiovocal syndrome is characterised by vocal cord paralysis due to a cardiovascular disease. A wide spectrum of conditions can result in this syndrome. Here we present a case of cardiovocal syndrome in association with primary pulmonary hypertension. Laryngeal electromyography was used to guide the work-up of differential diagnosis and also for further intervention with respect to vocal cord paralysis in this patient.

Anatomical localization of the motor entry point in the thyroarytenoid muscle.

INTRODUCTION: The aim of this study was to localize the motor entry point (MEP) of the thyroarytenoid muscle. METHODS: Eight cadaver larynges were dissected. A virtual plane was used to represent the MEP in a coordinate (X/Y/Z) system. The inferior border of the thyroid cartilage was linked to the center of the anterior arc of the cricoid cartilage (the Y-axis). The X-axis was set perpendicular to the Y-axis; the Z-axis passed through the posterior border of the thyroid lamina from the height of the insertion point. RESULTS: The mean X, Y, and Z coordinates were 6.2 mm, 9.1 mm, and 11.0 mm, respectively. The calculated angles of the lateral and superior deflections were 29.4° and 35.8°, respectively. The calculated insertion depth, that is, the distance from the insertion point to the MEP, was 15.6 mm. CONCLUSIONS: These results may help to improve the accuracy of needle insertion during diagnostic laryngeal electromyography or laryngeal electromyography-guided injections.

Value of Laryngeal Electromyography in Spasmodic Dysphonia Diagnosis and Therapy.

OBJECTIVE: To investigate the role of laryngeal electromyography (LEMG) in the diagnosis and treatment of spasmodic dysphonia (SD). METHODS: The clinical manifestations, characteristics of motor unit potentials (MUPs), recruitment potentials, and laryngeal nerve evoked potentials (EPs) in LEMG, as well as the changes after botulinum toxin (BTX) treatment, were analyzed in 39 patients with adductor SD. RESULTS: The main clinical manifestations were a strained voice and phonation interruptions; in addition, the patients displayed hyper-adducted vocal folds during phonation. LEMG revealed significantly increased amplitudes of the thyroarytenoid muscle MUPs. The recruitment potentials were in a dense bunch, discharging full interference patterns with significantly increased amplitudes; the mean and maximum amplitude of recruitment potentials were 3090 µV and 5000 µV, respectively. The amplitude of EPs of thyroarytenoid muscle increased significantly; the mean and maximum amplitudes were 10.3 mV and 26.3 mV, respectively. After BTX was injected, the LEMG revealed denervation changes, and the EPs weakened or disappeared in the injected muscle. CONCLUSIONS: SD could be diagnosed, and the therapeutic efficacy of SD treatments could be evaluated based on clinical characteristics combined with LEMG characteristics. The increased amplitudes of the recruitment potentials and EPs of the thyroarytenoid muscle were the characteristic indexes. After BTX was injected, denervated potential characteristics appeared in the muscles.

Prospective investigation of nimodipine for acute vocal fold paralysis.

INTRODUCTION: Nimodipine has been shown to be beneficial for recovery from acute vocal fold paralysis (AVFP) in an animal model. METHODS: prospective, open-label trial of patients with AVFP was performed using nimodipine. Consecutive patients were evaluated and offered nimodipine therapy. RESULTS: Fifty-three patients were considered for treatment with nimodipine. Thirteen did not qualify for inclusion, 5 were lost to follow-up, and 7 had side effects requiring cessation of treatment. Thus 28 patients (30 paralyzed vocal folds) were analyzed. Eighteen of the paralyzed vocal folds experienced recovery of purposeful motion (60%). Historical controls and laryngeal electromyography meta-analysis suggest no more than a 20% recovery rate from AVFP. CONCLUSIONS: This open label study using nimodipine for treatment of AVFP demonstrates tripling of the recovery rate of vocal fold motion compared with historical controls. Further study in a randomized, controlled manner is warranted.

Technical Challenges for Laryngeal Electromyography.

BACKGROUND/OBJECTIVE: Laryngeal electromyography (LEMG) is a useful diagnostic test in the evaluation of vocal fold paralysis (VFP). This study investigates factors that can make LEMG challenging to perform. METHODS: Patients with subacute unilateral VFP presented for LEMG were prospectively enrolled. Demographic data including BMI, previous neck surgery, and anatomic factors were collected. Patient-reported pain related to the procedure was recorded on a visual analogue scale (VAS). Electromyographer and otolaryngologist recorded a consensus rating of the perceived difficulty in performing the test and confidence in using the results for clinical decision-making. RESULTS: A total of 111 patients (56.8% female) were enrolled between August 2015 and August 2018. The mean age was 55 ± 14 years, and the average body mass index (BMI) was 28.5 ± 6.4. The mean patient-reported VAS score for pain was 35 ± 24. Notably, 31.2% of the tests were considered "very easy," 32.1% were considered "mildly challenging" and 23.9% and 12.8% were considered "moderately challenging" and "extremely challenging," respectively, by the clinicians. Common factors affecting LEMG difficulty included poorly palpable surface anatomy (50.5%) and patient intolerance (15.6%). Clinicians felt confident in 76.1% of the test findings. Bivariate analyses showed that prior neck surgery is associated with elevated VAS (p = 0.02), but clinician-perceived difficulty of performing the test is not associated with elevated VAS scores (p = 0.55). CONCLUSIONS: Majority of LEMG tests are well tolerated by patients. Physicians reported more confidence using LEMG for clinical decision-making when the test was easier to perform. Difficult surface anatomy and patient intolerance affects clinician confidence in integrating the test results with clinical care. LEVEL OF EVIDENCE: 3 Laryngoscope, 134:831-834, 2024.