Mild Vocal Fold Paresis: Understanding Clinical Presentation and Electromyographic Findings

The implications of mild vocal fold hypomobility are incompletely understood. This study describes the clinical, electromyographic, and probable etiologic findings in patients who presented with complaints of dysphonia and whose physical examination revealed vocal fold paresis as a factor possibly contributing to their voice complaints. A retrospective chart review of all patients who presented to a tertiary laryngology referral center over a 13-month period, who had a clinical diagnosis of mild vocal fold hypomobility and who underwent laryngeal electromyography, were included in the study. A total of 22 patients completed the medical evaluation of their voice complaint. Of these patients, 19 (86.4%) were found to have evidence of neuropathy on laryngeal electromyography. The clinical picture indicated the following probable origins for the vocal fold paresis: goiter/thyroiditis (7/22 or 31.8%), idiopathic (4/22 or 18.2%), viral neuritis (4/22 or 18.2%), trauma (3/22 or 13.6%), and Lyme's disease (1/22 or 4.5%). This article describes the clinical entity of mild vocal fold hypomobility and associated flexible laryngoscopic, rigid strobovideolaryngoscopic, and laryngeal electromyographic findings.     

Superior laryngeal nerve paresis and paralysis

Superior laryngeal nerve paresis and paralysis are relatively common but often difficult to diagnose with certainty. They are most commonly caused by viral infections, though other etiologies must be considered. A thorough history and physical examination, including strobovideolaryngoscopy and laryngeal electromyography, are needed for definitive diagnosis. It is essential to establish the diagnosis accurately to differentiate an apparent superior laryngeal nerve paresis from other conditions, such as myasthenia gravis. Laryngeal electromyography is used to confirm clinical impressions, as a guide for therapy, and as one measure of recovery. In our experience, accurate and early diagnosis assure the best phonatory outcome by directing therapy that will prevent or eliminate compensatory vocal abuses, which may themselves lead to even more serious vocal injury.     

Strobovideolaryngoscopic Findings in Singing Teachers

Professional voice users often present to otolaryngologists and laryngologists with specific voice complaints. The contributions of pathologic lesions to the patients' vocal complaints are not always clear on examination, and often, premorbid examinations of the larynx are not available for review. This study examines the incidence of laryngeal pathology among singing teachers. At a national convention of singing teachers, volunteers were recruited for a "free strobovideolaryngoscopic examination." All volunteers completed a detailed questionnaire of their vocal and medical history and underwent strobovideolaryngoscopic examination. Strobovideolaryngoscopic examinations were completed in 20 volunteers, 7 of whom had voice complaints and 13 of whom perceived their voices to be normal. Vocal fold masses were common among the asymptomatic singing teachers. Evidence of reflux laryngitis was a common finding among both symptomatic and asymptomatic singing teachers. Asymmetries in vocal fold hypomobility were more common among those with voice complaints than was the presence of vocal fold masses in the population studied.     

Vocal Fold Paralysis Following Radiotherapy for Nasopharyngeal Carcinoma: Laryngeal Electromyography Findings

Laryngeal electromyography was used to study the pattern of neurological injury in three patients with unilateral vocal fold paralysis following radiotherapy for nasopharyngeal carcinoma. The thyroarytenoid and cricothyroid muscles were assessed to give an indication of recurrent and superior laryngeal nerve function. Two patients demonstrated both recurrent and superior laryngeal neuropathy suggesting injury at the skull base. The other patient had only recurrent laryngeal neuropathy indicating more distal involvement. Subclinical neuropathic changes were seen in two cases on the side contralateral to the vocal fold paralysis. These patients may be at increased risk of developing bilateral vocal fold paralysis and potentially life-threatening airway obstruction. Long-term follow-up is recommended for such patients, especially if medialization thyroplasty is being considered. This is the first report describing the use of electromyography to determine the pattern of nerve injury in patients with vocal fold paralysis following head and neck radiotherapy.     

Complications of collagen injection of the vocal fold: report of several unusual cases and review of the literature

Injection laryngoplasty is one of the most frequently performed procedures in patients with voice complaints. Various biomaterials have been used to medialize vocal folds or to treat symptoms of vocal fold scar. The ideal biomaterial would be easily injected through a fine-gauge needle, well tolerated, and long lasting. Injectable collagen preparations fulfill at least two of these criteria, and collagen has been used widely for vocal fold injections. MATERIALS AND METHODS: We present a retrospective review of two unusual complications of collagen injection and a review of the relevant literature on the complications of medical use of collagen compounds. RESULTS: Two patients in whom collagen was injected formed firm submucosal deposits that interrupted the normal mucosal wave and produced significant dysphonia. Surgical removal of these deposits restored the mucosal wave and improved voice quality. Management of this unusual complication of human collagen injection in the vocal fold has not been reported previously. Other complications of collagen injection include hypersensitivity reactions to bovine collagen, local abscess formation at injection sites, and possibly induction of collagen vascular disease in some patients. CONCLUSIONS: Although collagen injections of the vocal fold rarely result in complications, physicians using collagen must be familiar with the types of complications that can occur. Proper diagnosis and prompt management of complications can result in good outcomes.     

Objective Voice Measures in Nonsinging Patients With Unilateral Superior Laryngeal Nerve Paresis

The clinical value of objective voice measures in nonsinging patients with superior laryngeal nerve dysfunction is unknown. In this study, patients with symptomatic unilateral superior nerve paresis were evaluated for maximum phonation time, frequency range of phonation, and mean flow rate. Patients with coexisting pathology, bilateral superior nerve paresis, and those with recurrent laryngeal nerve paresis were excluded from this analysis. A total of 35 nonsinging patients, 14 men and 21 women, with unilateral superior laryngeal nerve paresis were examined between 1999 and 2002. The severity of superior laryngeal nerve paresis ranged from 25% to 85% of normal recruitment with a mean of 70% superior laryngeal nerve recruitment in men and 65% in women by electromyography. In both men and women with superior laryngeal nerve paresis, the maximum phonation time and frequency range of phonation were decreased and the mean air flow rate was increased when compared with normal population values. The jitter percent, shimmer percent, and noise-to-harmonic ratio were also increased in patients when compared with normative data. Selected objective voice measures are abnormal in voice patients with superior laryngeal nerve paresis, which suggests that the measures may be useful as outcomes measures after therapy. More research is encouraged.     

Voice range in superior laryngealnerve paresis and paralysis

Evaluation of Physiologic Frequency Range (PFR) and Musical FrequencyRange (MRP) of Phonation was performed on 56 adults (singers and nonsingers) presenting with superior laryngeal nerve (SLN) paresis or paralysis confirmed by laryngeal electromyography. The most common etiology was neuritis (69.7%), followed by iatrogenic and unlcnown causes,each accounting for 10.2 % of cases, and finally trauma (8.9%). Both female and male singers with SLN paresis or paralysis had significantly higher PFR and MPR than nonsingers. Female classical singers presented PFR and MPR of up to 10 semitones (ST) higher than nonclassical singers and nonsingers. The lowest PFR and musical ranges were found in patients with SLN paresis associated with recurrent laryngeal nerve paresis or paralysis. The authors suggest that voice range measurement is a useful parameter for analyzing the effects of SLN paresis or paralysis on voice and that it may also assist in measuring outcome following voice therapy.     

Recurrent Laryngeal Nerve Electrophysiologic Monitoring in Thyroid Surgery: The Standard of Care?

Reports in the literature suggest that the rate of transient and permanent vocal fold immobility (VFI) after thyroid surgery is 4% to 7% and 1% to 4%. The intraoperative use of nerve integrity monitors has been advocated to reduce the incidence of VFI during thyroid surgery. The purpose of this study was to compare postoperative VFI after unmonitored and monitored thyroid surgical procedures. The charts of 136 consecutive patients who underwent thyroid surgery from 1998 to 2003 were retrospectively surveyed. Fifty-four patients had total thyroidectomies, bringing the total recurrent laryngeal nerves (RLNs) dissected to 190. Three of 190 (1.6%) and 7 of 190 (3.7%) RLNs dissected had permanent and transient vocal fold dysfunction. Overall, 107 RLNs were unmonitored compared with 83 RLNs that were monitored. Unmonitored and monitored RLNs had a 4 of 83 (4.8%) versus 3 of 107 (2.8%) rate of transient VFI (P > 0.05). Unmonitored and monitored RLNs had a 1 of 107 (0.9%) versus 2 of 83 (2.4%) rate of permanent VFD (P > 0.05). Electrophysiologic RLN monitoring was not demonstrated in this study to reduce the incidence of transient or permanent VFI after thyroid surgery. Electrophysiologic RLN integrity does not always translate into clinical postoperative vocal fold mobility. Electrophysiologic RLN monitoring may support that the RLN was not severed in the patient with postoperative VFI.     

Electrophysiologic monitoring of the recurrent laryngeal nerves may not predict bilateral vocal fold immobility after thyroid surgery

Two cases of bilateral vocal fold immobility (VFI) after identification and preservation of the recurrent laryngeal nerves (RLNs) required tracheotomy until vocal fold recovery. The first patient underwent thyroid surgery without preoperative or postoperative evaluation of the vocal folds, administration of postoperative intravenous steroids, or electrophysiologic monitoring of the RLNs, whereas the second patient underwent a thyroid procedure in which all of the aforementioned were executed. Preoperative and postoperative clinical evaluation of the RLNs is strongly suggested in patients undergoing thyroid surgery, especially revision surgery. Patients potentially undergoing total thyroidectomy should be counseled about the remote chance of airway obstruction and should be properly selected for this operation. Subclinical stretching of the RLNs or ischemia from the endotracheal tube cuff can result in unilateral VFI, and rarely bilateral VFI, requiring reintubation, tracheotomy, or vocal fold lateralization. Electrophysiologic monitoring may not always predict bilateral VFI.     

Vocal fold augmentation with injectable calcium hydroxylapatite: short-term results.

Symptoms of unilateral vocal fold paralysis are improved significantly by augmenting the paralyzed vocal fold via vocal fold injection. In this trial, augmentation with a new calcium hydroxylapatite implant was evaluated. In addition, two different phonosurgical injection techniques were used, and these procedures were compared for accuracy and reliability. A total of 11 terminal patients with unilateral vocal fold paralysis underwent vocal fold injection with calcium hydroxylapatite. Efficacy of the implant was evaluated by comparing results from the Voice Handicap Index (VHI) and mean airflow measurements before and 6 months after injection. Surgeon evaluations determined the comparative benefits of either endoscopic direct vocal fold injection or percutaneous vocal fold injection. Six-month data were obtained for a cohort of five patients. VHI scores improved for all five patients available for full evaluation and four of the five achieved improvements in mean airflow rates. Of the remaining patients, one later had a medialization laryngoplasty, two died from their terminal diseases before the 6-month follow-up, and two of the remaining three reported satisfaction with the results via telephone follow-up. Vocal fold injection via endoscopic, direct laryngoscopy was found to be a more reliable procedure for vocal fold injection than percutaneous injection. Slight overinjection (10% to 15%) was found to provide optimum results. Vocal fold injection of calcium hydroxylapatite for unilateral vocal fold paralysis improved voice quality and reduced mean airflow rates in this patient group with short-term results. Long-term studies are needed to confirm the durability of these findings.     

Vocal fold paralysis secondary to cardiac countershock (cardioversion)

Application of electrical energy to the heart is effective in treating many dysrhythmias. There are, however, also disadvantages associated with cardioversion. Employment of external electrical current has been shown to induce epicardial and myocardial damage at the site of electrode application. We present the only case in the English literature of vocal fold paralysis in which the single identified associated event was cardioversion. In this case of temporary vocal fold paralysis, there was no invasive procedure to directly damage the nerve. Echocardiography of the patient revealed a large left atrium, placing the recurrent laryngeal nerve in an abnormal anatomic position where it was vulnerable to the electric current.     

Multiparametric Analysis of Vocal Fold Vibrations in Healthy and Disordered Voices in High-Speed Imaging

Objectives

The aim of this study was to look for visual subjective and objective parameters of vocal fold dynamics being capable of differentiating healthy from pathologic voices in daily clinical practice applying endoscopic high-speed digital imaging (HSI).

Study Design and Methods

Four hundred ninety-six datasets containing 80 healthy and 416 pathologic subjects (232 functional dysphonia (FD), 13 bilateral, and 171 unilateral vocal fold nerve paralysis) were analyzed retrospectively. Videos at 4000 Hz (256 × 256 pixel) were recorded during sustained phonation. Subjective parameters were visually evaluated and complemented by an analysis of objective parameters. Visual subjective parameters were mucosal wave, glottal closure type, glottal closure insufficiency (GI), asymmetries of the vocal folds, and phonovibrogram (PVG) symmetry. After image segmentation, objective parameters were computed: closed quotient, perturbation measures (PMs) of glottal area, and left-right asymmetry values.

Results

HSI evaluation enabled to distinguish healthy from pathologic voices. For visual subjective parameters, GI, symmetrical behavior, and PVG symmetry exhibited statistical significant differences. For 95% of the data, objective parameters could be computed. Among objective parameters, closed quotient, jitter, shimmer, harmonic-to-noise ratio, and signal-to-noise ratio for the glottal area function differentiated statistically significant normal from pathologic voices. Applying linear discriminant analysis by combining visual subjective and objective parameters, accurate classifications were made for 63.2% of the female and 87.5% of the male group for the three-class problem (healthy, FD, and unilateral vocal fold nerve paralysis).

Conclusion

Actual acoustically applied PMs can be transferred to clinical beneficial HSI analysis. Combining visual subjective and objective basic parameters succeeds in differentiating pathologic from healthy voices. The presented evaluation can easily be included into everyday clinical practice. However, further research is needed to broaden our understanding of the variability within and across healthy and pathologic vocal fold vibrations for diagnosing voice disorders and therapy control.     

Voice and Laryngeal Configuration of Men With Unilateral Vocal Fold Paralysis Before and After Medialization

Aim

To describe the laryngeal configuration and the voice of male patients diagnosed with unilateral vocal fold paralysis (UVFP) before and after medialization.

Methods

A retrospective study involving the collection of data from medical records of 142 patients diagnosed with UVFP from January 2003 to April 2009, submitted to auditory-perceptual assessment of voices and visual perception of laryngeal images before and after medialization.

Results

The study included data from 24 male patients, with an average of 60.7 years, who underwent three surgical medialization techniques (injection of hyaluronic acid, type I thyroplasty, and injection of Teflon). Before treatment, the position of the paralyzed vocal fold was seen to have a significant influence to the passing of the healthy vocal fold beyond the midline and on the overall degree of dysphonia. After treatment, the complete glottic closure; the free margin of the linear vocal fold; paralyzed vocal fold in the median position, reduction of hoarseness, roughness and breathiness (more frequently mild), and asthenia (more frequently normal and mild); tension and instability (more frequency normal); and a decrease in the overall degree of dysphonia were found to be significant.

Conclusion

The position of the paralyzed vocal fold influences the position of the healthy vocal fold in relation to the midline and the overall degree of dysphonia. All three treatments improved the glottic configuration and the voice of patients with UVFP.     

Long-term preservation of voice improvement following surgical medialization and reinnervation for unilateral vocal fold paralysis

In June of 1996, we reported improved functional voice results when reinnervation was combined with surgical medialization for unilateral vocal fold paralysis. In addition, it was noted that further wasting of the reinnervated vocal fold was prevented in 96% of these patients beyond 2 years' follow-up. The study reported here compares the long-term preservation of voice improvement achieved by surgical medialization alone with that resulting from combined medialization and nerve-muscle pedicle reinnervation. Further significant wasting of the paralyzed vocal fold with voice deterioration from that achieved by surgical medialization alone was noted between 6 months and 2 years postoperatively in 28% of patients, while only 4% of those undergoing combined reinnervation demonstrated this finding at a minimum of 2 years' follow-up.     

Arytenoid Cartilage Dislocation: A 20-year Experience

SUMMARY: Arytenoid cartilage dislocation is an infrequently diagnosed cause of vocal fold immobility. Seventy-four cases have been reported in the literature to date. Intubation is the most common origin, followed by external laryngeal trauma. Decreased volume and breathiness are the most common presenting symptoms. We report on 63 patients with arytenoid cartilage dislocation treated by the senior author (RTS) since 1983. Significantly more posterior than anterior dislocations were represented. Although reestablishing joint mobility is difficult, endoscopic reduction should be considered to align the heights of the vocal processes. This process may result in significant voice improvement even long after the dislocation. Strobovideolaryngoscopy, laryngeal electromyography, and laryngeal computed tomography (CT) imaging are helpful in the evaluation of patients with vocal fold immobility to help distinguish arytenoid cartilage dislocation from vocal fold paralysis. Familiarity with signs and symptoms of arytenoid cartilage dislocation and current treatment techniques improves the chances for optimal therapeutic results.     

Repetitive Phonatory Tasks for Identifying Vocal Fold Paresis

Vocal fold paresis may be present in patients with voice complaints. Identification of paresis is important so that appropriate neurolaryngologic evaluation can be ordered and the appropriate treatment can be offered. Repetitive phonatory tasks (RPTs) fatigue patients vocally and may elicit signs of subtle paresis. In this study, four laryngologists independently reviewed the RPT portions of routine fiberoptic voice examinations of 100 patients in a blinded fashion. All patients had presented with voice complaints, were suspected of having a movement disorder of the larynx, and had been referred for laryngeal electromyography (LEMG). Predictions were compared with LEMG results and with predictions made at the time of each initial evaluation. Although RPTs are useful to laryngologists, predictions based on the entire examination are more accurate. LEMG can confirm clinical suspicions or identify paresis missed on fiberoptic laryngeal examination.     

Etiology, pathophysiology, treatment choices, and voice results for unilateral adductor vocal fold paralysis: A 3-year retrospective

Unilateral vocal fold paralysis is now considered a common disorder seen in the practice of otolaryngology and voice pathology. Concern first is for the accurate diagnosis of the associated etiology in an efficient and thorough fashion. When etiology has been determined the focus of treatment becomes the management of the presenting symptoms, which typically include dysphonia and dysphagia. A retrospective study was conducted reviewing the records of 117 patients with unilateral adductor vocal fold paralysis who presented to a large otolaryngology practice and clinical voice lab from 1995 to 1998. Demographic data reveal most patients to range in age from 16 to 91 with a dominant clustering for ages 50 to 70. Gender distribution reveals males slightly exceed females in this sample. Data regarding etiology type are collected in great detail, revealing that disease and surgery involving the chest contribute the greatest to the overall number in this study and that anterior approach to cervical spine surgery contributes as much as thyroid surgery. General outcomes of the patients are reviewed. A small group (n = 25) of patients who had pretreatment and posttreatment data available revealed statistically significant differences between voice outcomes for patients who were treated with medialization and for those treated with therapy. Patients receiving therapy had less severe symptoms pretreatment, while greater gains pretreatment to posttreatment were shown for those who had surgical medialization.     

Laryngeal Myasthenia Gravis: Report of 40 Cases

Myasthenia gravis, an autoimmune disorder of the neuromuscular junction, is usually recognized because of ocular complaints or generalized weakness. We report a series of 40 patients who presented with dysphonia as their initial and primary complaint. Diagnostic testing included strobovideolaryngoscopy, electromyography (EMG) with repetitive stimulation and Tensilon testing, and laboratory and radiographic evaluation. Strobovideolaryngoscopy most commonly revealed fluctuating impairment of vocal fold mobility, either unilateral or bilateral. EMG detected evidence of neuromuscular junction abnormalities in all patients. Only one patient had evidence of antiacetylcholine receptor (ACh-R) antibodies, but many other abnormalities suggestive of autoimmune dysfunction were present. Pyridostigmine therapy was initiated in 34 patients but was not tolerated in 4. Of the remaining 30 patients, 23 reported improvement of symptoms. We conclude that myasthenia gravis can present with symptoms confined primarily to the larynx and should be included in the differential diagnosis of dysphonia.     

Unilateral recurrent laryngeal nerve paralysis:The importance of “preoperative” voice therapy

This preliminary retrospective study of 19 female patients and 22male patients with unilateral recurrent nerve lesions demonstrated the promise of objective measurements in predicting the need for surgery, the efficacy of voice therapy in ameliorating vocal symptoms, and the effects of therapy in conjunction with surgery. Sixty-eight percent (68%) of the female patients and 64% of the male patients did not elect to have surgery. Outcome satisfaction of nonsurgical and surgical patients appeared to be similar. The data from this study support the importance of preoperative therapy for patients with unilateral vocal fold paralysis.     

Preliminary Results of a New Temporary Vocal Fold Injection Material

Temporary vocal fold injection is a valuable procedure for vocal fold paralysis or paresis of uncertain permanency and as a trial augmentation to decide the value of vocal fold augmentation. A new material made from glycerin, carboxymethylcellulose, and water has recently been developed for temporary vocal fold augmentation. Eleven patients underwent vocal fold injection for the treatment of glottal incompetence with this material. The duration of effectiveness of this injection material was 2 to 3 months depending on the injection amount. This new material satisfies several requirements for an ideal temporary vocal fold injection material in terms of injectability, convenience, duration of effectiveness, and safety. The authors conclude that this new material is a good option for temporary vocal fold augmentation.