Diagnostic laryngeal endoscopy

Differences in Glottal Closure and Visibility of the Anterior Commissure during Rigid-90°, Rigid-70°, and Flexible Laryngostroboscopy

INTRODUCTION

The conventional rigid-90° and rigid-70° laryngostroboscopy has been so far considered the gold standard in assessing the vibratory behavior of the vocal folds and the glottal closure configuration during phonation. Meanwhile, this rigid laryngostroboscopy is more and more replaced by flexible chip-on-tip systems. The aim of this study was to evaluate the influence of these different endoscopic techniques on glottal closure configuration and on visibility of the complete focal fold length including anterior commissure during phonation.

METHODS

Twenty-one euphonic subjects were enrolled (mean age 34.6 ± 9.5; m = 10, f = 11). They were examined with the three laryngoscopic techniques (conventional rigid-90°, rigid-70°, and flexible chip-on-tip laryngoscopy during low and high voice pitch with soft and loud voice intensity). For evaluating the degree of glottal closure, a modified classification of Södersten et al. was applied and the visibility of the anterior commissure was evaluated. The correlation of the three endoscopic techniques was assessed with Cohen and Fleiss' kappa.

RESULTS

In even low loud phonation, the rigid-90° and rigid-70° endoscopies revealed a complete closure of the glottis in only 47.6% of subjects but with flexible endoscopy in 81%. The complete vocal fold length with anterior commissure was best visible with flexible endoscopy in 90.5% in low-soft and high-soft phonation. The rigid-90° endoscopy showed a slight agreement in comparison with the flexible endoscopy in regard to the types of vocal fold closure with a Cohen's kappa coefficient k = 0.199. The rigid-90° endoscopy showed an almost perfect agreement with k = 0.84 when compared to the rigid-70° endoscopy. The flexible endoscopy compared to the rigid-70° endoscopy showed a fair agreement with k = 0.346.

CONCLUSION

We found mainly corresponding results in both rigid-90° and rigid-70° endoscopic techniques which can be explained by the same transoral approach with the tongue pulled out, whereas the flexible transnasal endoscopy mainly gives a better view on the anterior commissure. The influence of transorally or transnasally guided endoscopic techniques needs to be considered in interpretation of laryngostroboscopic parameters like vocal fold closure and supraglottal hyperactivity.

Phoniatricians and otorhinolaryngologists approaching oropharyngeal dysphagia: an update on FEES

PURPOSE

Oropharyngeal dysphagia (OD) is a common phenomenon in otorhinolaryngology and phoniatrics. As both sub-disciplines have a strong tradition and clinical experience in endoscopic assessment of the upper aerodigestive tract, the implementation of fiberoptic endoscopic evaluation of swallowing (FEES) was an almost self-evident evolution. This review aims to provide an update on FEES and the role of phoniatricians and otorhinolaryngologists using FEES in Europe.

METHODS

A narrative review of the literature was performed by experts in the field of FEES both in the clinical context and in the field of scientific research.

RESULTS

FEES is the first-choice OD assessment technique for both phoniatricians and otorhinolaryngologists. FEES is becoming increasingly popular because of its usefulness, safety, low costs, wide applicability, and feasibility in different clinical settings. FEES can be performed by health professionals of varying disciplines, once adequate knowledge and skills are acquired. FEES aims to determine OD nature and severity and can provide diagnostic information regarding the underlying etiology. The direct effect of therapeutic interventions can be evaluated using FEES, contributing to design the OD management plan. Standardization of FEES protocols and metrics is still lacking. Technological innovation regarding image resolution, frame rate frequency, endoscopic light source specifications, and endoscopic rotation range has contributed to an increased diagnostic accuracy.

CONCLUSION

The rising number of phoniatricians and otorhinolaryngologists performing FEES contributes to the early detection and treatment of OD in an aging European population. Nevertheless, a multidisciplinary approach together with other disciplines is crucial for the success of OD management.

LaDIVA: A neurocomputational model providing laryngeal motor control for speech acquisition and production

Many voice disorders are the result of intricate neural and/or biomechanical impairments that are poorly understood. The limited knowledge of their etiological and pathophysiological mechanisms hampers effective clinical management. Behavioral studies have been used concurrently with computational models to better understand typical and pathological laryngeal motor control. Thus far, however, a unified computational framework that quantitatively integrates physiologically relevant models of phonation with the neural control of speech has not been developed. Here, we introduce LaDIVA, a novel neurocomputational model with physiologically based laryngeal motor control. We combined the DIVA model (an established neural network model of speech motor control) with the extended body-cover model (a physics-based vocal fold model). The resulting integrated model, LaDIVA, was validated by comparing its model simulations with behavioral responses to perturbations of auditory vocal fundamental frequency (fo) feedback in adults with typical speech. LaDIVA demonstrated capability to simulate different modes of laryngeal motor control, ranging from short-term (i.e., reflexive) and long-term (i.e., adaptive) auditory feedback paradigms, to generating prosodic contours in speech. Simulations showed that LaDIVA's laryngeal motor control displays properties of motor equivalence, i.e., LaDIVA could robustly generate compensatory responses to reflexive vocal fo perturbations with varying initial laryngeal muscle activation levels leading to the same output. The model can also generate prosodic contours for studying laryngeal motor control in running speech. LaDIVA can expand the understanding of the physiology of human phonation to enable, for the first time, the investigation of causal effects of neural motor control in the fine structure of the vocal signal.

A Portable Smartphone-Based Laryngoscope System for High-Speed Vocal Cord Imaging of Patients With Throat Disorders: Instrument Validation Study

Background

Currently, high-speed digital imaging (HSDI), especially endoscopic HSDI, is routinely used for the diagnosis of vocal cord disorders. However, endoscopic HSDI devices are usually large and costly, which limits access to patients in underdeveloped countries and in regions with inadequate medical infrastructure. Modern smartphones have sufficient functionality to process the complex calculations that are required for processing high-resolution images and videos with a high frame rate. Recently, several attempts have been made to integrate medical endoscopes with smartphones to make them more accessible to people in underdeveloped countries.

Objective

This study aims to develop a smartphone adaptor for endoscopes, which enables smartphone-based vocal cord imaging, to demonstrate the feasibility of performing high-speed vocal cord imaging via the high-speed imaging functions of a high-performance smartphone camera, and to determine the acceptability of the smartphone-based high-speed vocal cord imaging system for clinical applications in developing countries.

Methods

A customized smartphone adaptor optical relay was designed for clinical endoscopy using selective laser melting–based 3D printing. A standard laryngoscope was attached to the smartphone adaptor to acquire high-speed vocal cord endoscopic images. Only existing basic functions of the smartphone camera were used for HSDI of the vocal cords. Extracted still frames were observed for qualitative glottal volume and shape. For image processing, segmented glottal and vocal cord areas were calculated from whole HSDI frames to characterize the amplitude of the vibrations on each side of the glottis, including the frequency, edge length, glottal areas, base cord, and lateral phase differences over the acquisition time. The device was incorporated into a preclinical videokymography diagnosis routine to compare functionality.

Results

Smartphone-based HSDI with the smartphone-endoscope adaptor could achieve 940 frames per second and a resolution of 1280 by 720 frames, which corresponds to the detection of 3 to 8 frames per vocal cycle at double the spatial resolution of existing devices. The device was used to image the vocal cords of 4 volunteers: 1 healthy individual and 3 patients with vocal cord paralysis, chronic laryngitis, or vocal cord polyps. The resultant image stacks were sufficient for most diagnostic purposes. The cost of the device including the smartphone was lower than that of existing HSDI devices. The image processing and analytics demonstrated the successful calculation of relevant diagnostic variables from the acquired images. Patients with vocal pathologies were easily differentiable in the quantitative data.

Conclusions

A smartphone-based HSDI endoscope system can function as a point-of-care clinical diagnostic device. The resulting analysis is of higher quality than that accessible by videostroboscopy and promises comparable quality and greater accessibility than HSDI. In particular, this system is suitable for use as an accessible diagnostic tool in underdeveloped areas with inadequate medical service infrastructure.

Preoperative rigid laryngoscopic examination and modified jaw thrust manoeuver during fibreoptic-assisted tracheal intubation for general anaesthesia

Preoperative laryngoscopic examination of the airway informs general anaesthesia management and planning. However, the same glottic opening view cannot always be obtained during direct laryngoscopy of anaesthetised patients. In this case report, a patient underwent preoperative rigid laryngoscopy due to medical history, and no problems were anticipated in performing tracheal intubation; however, the direct laryngoscopic view was a Grade 4 on the Cormack-Lehane Scale after anaesthesia induction. A jaw thrust manoeuvre to facilitate fibreoptic-assisted nasotracheal intubation was not feasible. In order to compensate, a modified method of jaw thrust was implemented, where both thumbs were placed on the floor of the patient's mouth, leading to a successful result. Safe airway management should be implemented with proper planning based on a careful preoperative evaluation.

High-resolution magnetic resonance and mass spectrometry imaging of the human larynx

High-resolution, noninvasive and nondestructive imaging of the subepithelial structures of the larynx would enhance microanatomic tissue assessment and clinical decision making; similarly, in situ molecular profiling of laryngeal tissue would enhance biomarker discovery and pathology readout. Towards these goals, we assessed the capabilities of high-resolution magnetic resonance imaging (MRI) and matrix-assisted laser desorption/ionisation-mass spectrometry (MALDI-MS) imaging of rarely reported paediatric and adult cadaveric larynges that contained pathologies. The donors were a 13-month-old male, a 10-year-old female with an infraglottic mucus retention cyst and a 74-year-old female with advanced polypoid degeneration and a mucus retention cyst. MR and molecular imaging data were corroborated using whole-organ histology. Our MR protocols imaged the larynges at 45-117 μm² in-plane resolution and capably resolved microanatomic structures that have not been previously reported radiographically-such as the vocal fold superficial lamina propria, vocal ligament and macula flavae; age-related tissue features-such as intramuscular fat deposition and cartilage ossification; and the lesions. Diffusion tensor imaging characterised differences in water diffusivity, primary tissue fibre orientation, and fractional anisotropy between the intrinsic laryngeal muscles, mucosae and lesions. MALDI-MS imaging revealed peptide signatures and putative protein assignments for the polypoid degeneration lesion and the N-glycan constituents of one mucus retention cyst. These imaging approaches have immediate application in experimental research and, with ongoing technology development, potential for future clinical application.

Transnasal Flexible Laryngoscopy Using Different Topical Preparations and Methods of Application-A Randomized Study

BACKGROUND

The field of laryngology has grown exponentially since the advent of the transnasal flexible laryngoscopy. Flexible laryngoscopy when performed skillfully using the proper technique, facilitates a good view of the hidden areas of the larynx.

OBJECTIVE

To compare the effectiveness of the topical agents in providing a more comfortable experience for the patient, allowing the practitioner to advance the endoscope with less friction, pain and discomfort for the patient using 10% lidocaine spray, 2% lidocaine gel, 4% lidocaine with xylometazoline (1:1) soaked pledgets, or aqueous gel.

MATERIALS AND METHODS

A prospective randomized single-blinded clinical trial was conducted in a tertiary care teaching hospital in South India where 376 patients were recruited and allocated into four groups based on the topical preparation used. Following endoscopy, each subject filled a questionnaire grading their experience on a visual analogue scale. The clinician also then answered a questionnaire on aspects of the endoscopy performed.

RESULTS

The pain score and the ease of performing the procedure among the different groups were comparable. Those in the 10% lidocaine arm experienced significant burning sensation (P = 0.0001). The other variables such as throat pain (P = 0.783), gag reflex (P = 0.318), unpleasant taste (P = 0.092), globus (P = 0.190), swallowing difficulty after the procedure (P = 0.273), difficulty in breathing (P = 0.744) and willingness to have a repeat procedure (P = 0.883) were also comparable.

CONCLUSION

Aqueous gel can be used topically during a flexible nasopharyngolaryngoscopy instead of an anesthetic agent alone or one combined with a nasal decongestant.

Efficacy of Conversation Training Therapy for Patients With Benign Vocal Fold Lesions and Muscle Tension Dysphonia Compared to Historical Matched Control Patients

Purpose Conversation training therapy (CTT) is the 1st voice therapy approach to eliminate the traditional therapeutic hierarchy and use patient-driven conversation as the sole therapeutic stimulus. The purpose of this investigation was to determine the efficacy of CTT compared to standard-of-care voice therapy approaches for the treatment of patients with voice disorders. Method A prospective study of CTT treatment outcomes in adults with dysphonia due to primary muscle tension dysphonia or benign vocal fold lesions compared to age, gender, and diagnosis historical matched control (HMC) patients was used. The primary outcome was change in Voice Handicap Index-10 (VHI-10); secondary outcomes included acoustic, aerodynamic, and auditory-perceptual outcomes. Data were collected before treatment (baseline), at the start of each therapy session, 1 week after the final therapy session (short-term follow-up), and 3 months after the final therapy session (long-term follow-up). Results For the CTT group, statistically significant improvements were observed for VHI-10. Though statistically significant improvements were observed for the VHI-10 for the HMC group, the CTT group saw significantly greater improvement in VHI-10. Furthermore, equivalent gains were observed following only 2 sessions of CTT compared to 4-8 sessions of traditional therapy. Significant improvements in the CTT group were observed for cepstral peak prominence in a vowel, fundamental frequency, Cepstral Spectral Index of Dysphonia in a vowel and connected speech, vocal intensity, average airflow in speech in a reading passage, number of breaths and duration of reading passage, and auditory-perceptual measurement of overall voice severity. Conclusions Results support the hypothesis that training voice techniques in the context of spontaneous conversational speech improves patient perception of voice handicap and acoustic, aerodynamic, and auditory-perceptual voice outcomes both immediately following treatment and at long-term follow-up. CTT participants also demonstrated significantly larger decreases in VHI-10 compared to HMC participants who received standard-of-care, nonconversational, hierarchical-based voice therapy.

Evaluation of Vocal Fold Motion Abnormalities: Are We All Seeing the Same Thing?

OBJECTIVES

Flexible laryngoscopy is the principle tool for the evaluation of vocal fold motion. As of yet, no consistent, unified outcome metric has been developed for vocal fold paralysis/immobility research. The goal of this study was to evaluate vocal fold motion assessment (inter- and intra-rater reliability) among general otolaryngologists and fellowship-trained laryngologists.

STUDY DESIGN

Prospective video perceptual analysis study.

METHODS

Flexible laryngoscopic examinations, with sound, of 15 unique patient cases (20 seconds each) were sent to 10 general otolaryngologists and 10 fellowship-trained laryngologists blinded to clinical history. Reviewers were given written definitions of vocal fold mobility and immobility and two video examples. The cases included bilateral vocal fold mobility (six), unilateral vocal fold immobility (five), and unilateral vocal fold hypomobility (four). Five examinations were repeated to determine intra-rater reliability. Participants were asked to judge if there was or there was no purposeful motion, as described by written definitions, for each vocal fold (800 tokens in total).

RESULTS

Twenty reviewers (100%) replied. Both general otolaryngologists and fellowship-trained laryngologists had an overall inter-rater reliability of 95%. Difference in inter-rater reliability between the two groups of raters was negligible: 95% for general otolaryngologists and 97.5% for fellowship-trained laryngologists. There was no variability in intra-rater reliability within either rater group (99%).

CONCLUSION

Intra- and inter-rater agreement in determining whether the patient had purposeful vocal fold motion on flexible laryngoscopic examination was excellent in both groups. This study demonstrates that otolaryngologists can consistently and accurately judge the presence and the absence of vocal fold motion.

High- and ultrahigh-field magnetic resonance imaging of naïve, injured and scarred vocal fold mucosae in rats

Subepithelial changes to the vocal fold mucosa, such as fibrosis, are difficult to identify using visual assessment of the tissue surface. Moreover, without suspicion of neoplasm, mucosal biopsy is not a viable clinical option, as it carries its own risk of iatrogenic injury and scar formation. Given these challenges, we assessed the ability of high- (4.7 T) and ultrahigh-field (9.4 T) magnetic resonance imaging to resolve key vocal fold subepithelial tissue structures in the rat, an important and widely used preclinical model in vocal fold biology. We conducted serial in vivo and ex vivo imaging, evaluated an array of acquisition sequences and contrast agents, and successfully resolved key anatomic features of naïve, acutely injured, and chronically scarred vocal fold mucosae on the ex vivo scans. Naïve lamina propria was hyperintense on T1-weighted imaging with gadobenate dimeglumine contrast enhancement, whereas chronic scar was characterized by reduced lamina propria T1 signal intensity and mucosal volume. Acutely injured mucosa was hypointense on T2-weighted imaging; lesion volume steadily increased, peaked at 5 days post-injury, and then decreased – consistent with the physiology of acute, followed by subacute, hemorrhage and associated changes in the magnetic state of hemoglobin and its degradation products. Intravenous administration of superparamagnetic iron oxide conferred no T2 contrast enhancement during the acute injury period. These findings confirm that magnetic resonance imaging can resolve anatomic substructures within naïve vocal fold mucosa, qualitative and quantitative features of acute injury, and the presence of chronic scar.

Summary: Magnetic resonance imaging is shown to allow the nondestructive assessment of acute injury and scar formation in vocal fold mucosa, as demonstrated ex vivo using a preclinical rat model.

Impact of topical anesthesia on acoustic characteristics of voice during laryngeal telescopic examination

OBJECTIVE:

The purposes of this study are to investigate the impact of topical anesthetic alone and with concurrent laryngeal telescopic examination on acoustic characteristics of vocal fold function. Comparison with phonation in controlled conditions may imply diagnostic information from the examination.

STUDY DESIGN:

Thirty males evaluated as having a normal voice were included in the study. The subjects were asked to phonate sustained /i/ with a naturally comfortable pitch and loudness in three consecutive experimental sequences as “control condition,” “anesthetic condition,” and “telescopic condition.” Acoustic analysis of fundamental frequency, jitter, shimmer, and harmonic to noise ratio in the three different conditions were executed.

RESULTS:

The mean and standard deviation of Fo in control condition, anesthetic condition, and telescopic condition were 130.1 ± 18.5 Hz, 125.7 ± 19.7 Hz, and 173.2 ± 35.1 Hz, respectively. The telescopic condition showed more negative change than that in control condition and anesthetic condition in other parameters. There was a significant difference ( P < 0.001) between control condition and telescopic condition in all four parameters.

CONCLUSIONS:

This study showed that anesthesia has little effect on voice performance for subjects with a normal voice. On the other hand, the acoustic characteristics changed significantly during telescopic performance. When doing interpretation of acoustic data, the abnormality of the acoustic characteristics might be the result of the procedures and not reflect vocal pathology. Laryngeal variations due to manipulation of telescope should be ruled out.

Acoustic characteristics of different target vowels during the laryngeal telescopy

OBJECTIVE

The aim of this study was to investigate the acoustic characteristics of target vowels phonated in normal voice persons while performing laryngeal telescopy. The acoustic characteristics are compared to show the extent of possible difference to speculate their impact on phonation function.

METHODS

Thirty-four male subjects aged 20-39 years with normal voice were included in this study. The target vowels were /i/ and /ɛ/. Recording of voice samples was done under natural phonation and during laryngeal telescopy. The acoustic analysis included the parameters of fundamental frequency, jitter, shimmer and noise-to-harmonic ratio.

RESULTS

The sound of a target vowel /ɛ/ was perceived identical in more than 90% of the subjects by the examiner and speech language pathologist during the telescopy. Both /i/ and /ɛ/ sounds showed significant difference when compared with the results under natural phonation. There was no significant difference between /i/ and /ɛ/ during the telescopy.

CONCLUSION

The present study showed that change in target vowels during laryngeal telescopy makes no significant difference in the acoustic characteristics. The results may lead to the speculation that the phonation mechanism was not affected significantly by different vowels during the telescopy. This study may suggest that in the principle of comfortable phonation, introduction of the target vowels /i/ and /ɛ/ is practical.

Electromyographic laryngeal synkinesis alters prognosis in vocal fold paralysis

OBJECTIVES/HYPOTHESIS

Synkinesis, or misdirected reinnervation, is likely a confounder when predicting return of function of an immobile vocal fold. Currently, no information exists on the incidence of synkinesis in unilateral vocal fold immobility (UVFI) or the effect synkinesis has on prognosis and treatment. Our objective was to examine a vocal fold adductor synkinesis screening protocol using diagnostic laryngeal electromyography (LEMG). We aim to determine the effect of synkinesis on prognosis of recovery of purposeful vocal fold motion.

STUDY DESIGN

Retrospective review of LEMG data and patient charts from laryngology practice.

METHODS

A standardized LEMG analysis method to diagnose vocal fold adductory synkinesis was performed in 124 consecutive laryngeal electromyographic exams.

RESULTS

Synkinesis testing was positive in 12/124 patients (9.7%). Post hoc quantitative analysis of electromyographic recordings to compare motor unit potential amplitude in the thyroarytenoid/lateral cricoarytenoid complex during sustained phonation to those in the same muscle during a "sniff" revealed a significant difference in motor unit potential amplitude ratio for control subjects (0.32), those who recovered purposeful vocal fold motion (0.40), and those with vocal fold paralysis (0.96) (P = .001). The presence of synkinesis in patients with UVFI improved the negative predictive value of LEMG from 53% to 100% and the sensitivity from 56% to 100%.

CONCLUSIONS

Presence of laryngeal synkinesis using motor amplitude ratio criteria, in the setting of good voluntary motor unit recruitment and UVFI, downgrades a patient's prognosis to one that is poor for recovery. We propose this screening protocol as an adjunct to diagnostic LEMG.

Neurolaryngologic evaluation of the performer

Numerous neurologic diseases affect voice production either through direct effects on the larynx or by affecting muscles involved with support or resonation of the voice. Voice changes can be the initial presenting symptoms of neurodegenerative disorders, especially in patients who have increased awareness of their vocal quality. Some patients present to the otolaryngologist before the neurologist. The otolaryngologist must have an understanding and familiarity with laryngeal manifestations of neurodegenerative diseases to make the appropriate diagnosis in a timely fashion. Moreover, the otolaryngologist can play a significant role in the care of patients who have neurodegenerative disease. Video procedures for neurolaryngologic evaluation accompany this content online.

Strobovideolaryngoscopy and Laboratory Voice Evaluation

A complete and thorough vocal history and physical examination is the cornerstone of the evaluation of any patient who has a vocal complaint. Continued scientific progress in the understanding of vocal fold vibration and sound production combined with advances in technology have resulted in the availability of numerous supplemental diagnostic laboratory tools for an optimal voice evaluation. This article presents additional clinical tools accessible to the otolaryngologist that may aid in diagnosis and help elucidate difficult vocal tract pathology.

Acoustic Changes Related to Laryngeal Examination with a Rigid Telescope

The influence on voice quality of the insertion of endoscopic equipment with tongue anchoring and head position requirements during endoscopic evaluation has not been fully investigated. The present study attempted to examine the influence of: (1) the presence of a rigid endoscope and tongue anchoring, and (2) the angle of position technique (70-degree and 90-degree) on participants' vocal output during sustained production of the vowel /i/. Five acoustic measurements including fundamental frequency (F0) values, percent jitter values, relative average perturbation of F0 shimmer, and noise-to-harmonic ratios were used to represent participants' voice quality. Results indicated that F0 values were significantly influenced by the angle of sitting position, while percent jitter values, relative average perturbation of F0, shimmer, and noise- to-harmonic ratios were affected by the presence of a rigid endoscope and tongue anchoring.

Evaluating the effectiveness and efficiency of voice therapy using transnasal flexible laryngoscopy: a randomized controlled trial

Transnasal flexible laryngoscopy (TFL) is an examination of laryngeal anatomy and physiology using continuous light. TFL is being used increasingly by voice pathologists in treatment but with little scientific evidence to support it. The purpose of this study was to evaluate the effectiveness and efficiency of TFL as a therapeutic tool. The study used a prospective randomized controlled trial. Fifty dysphonic subjects were recruited and randomly assigned to either a traditional treatment group or a TFL-assisted treatment group. The effectiveness of voice therapy in both treatment groups was measured with a package of voice outcome measures. Subjects in both treatment groups demonstrated statistically significant improvements after voice therapy (perceptual auditory rating of voice quality measurement p < 0.01; instrumental electroglottographic measurement p < 0.01; patient questionnaire measurement p < 0.01). The time taken to complete treatment in both groups was recorded. The average (median) time taken to complete voice therapy in the TFL-assisted treatment group was 2 hours less than in the traditional treatment group (p < 0.01). Voice therapy with TFL as a therapy tool was effective and more efficient than traditional voice therapy.

Utility of laryngeal electromyography in predicting recovery after vocal fold paralysis

OBJECTIVES

To determine the value of laryngeal electromyography in predicting recovery after vocal fold paralysis and to determine what elements of laryngeal electromyography are most predictive of outcome.

DESIGN

Cohort study with retrospective data review.

SETTING

University voice center.

PARTICIPANTS

Consecutive sample of 31 patients with vocal fold paralysis diagnosed by indirect laryngoscopy, using either nasal insertion with a flexible nasopharyngoscope or peroral with a 70 degrees Hopkins rod. Inclusion criteria were that laryngeal electromyography had to have been performed between 21 days and 6 months from the onset of symptoms and patients must have been followed a minimum of 6 months.

INTERVENTIONS

Not applicable.

MAIN OUTCOME MEASURE

Vocal fold motion at 6 months from onset of symptoms.

RESULTS

Nine subjects (29%) had resolved vocal fold motion, whereas 22 (71%) had persistent vocal fold paralysis. By using our laryngeal electromyography paradigm, 4 of 6 patients with a laryngeal electromyography prognosis of excellent resolved. The predictive value for a negative test was 66.7%. For patients with a fair or poor prognosis, 5 of 25 resolved. The predictive value for a positive test was 80%. Only 8 of 22 patients with persistent vocal fold paralysis had fibrillations, and spontaneous activity was not significantly related to outcome. Patients with absent or greatly decreased motor unit recruitment had a significantly higher proportion of permanent vocal fold paralysis (P<.05). Stepwise forward logistic regression determined that prognosis by laryngeal electromyography and onset time were significant predictors of outcome (P<.01). The model predicted 44.4% of resolved cases, which represents a moderate prediction.

CONCLUSIONS

This study confirms the utility of laryngeal electromyography in assessing prognosis for recovery of vocal fold motion after laryngeal nerve injury. The results support our hypothesis that preset decision rules based on laryngeal electromyography data can be effectively used to determine a prognosis for recovery of vocal fold motion.

Acute management of the performing voice

Management of a singer's acute voice problem carries repercussions that may affect his or her career. When a vocalist develops a problem before a performance, the clinician is required to make a prompt diagnosis, determine the safety of the vocal performance, and provide treatment. The ability of the singer to fulfill the pending vocal performance is also of paramount importance. Therefore, it is important for the clinician to understand the presenting complaints, to evaluate the emergent vocal need of the singer, and to combine the art and science of laryngology to formulate the treatment plan.