Stroboscopy as a Research Instrument: Development of a Perceptual Evaluation Tool

Analyzing Vocal Fold Frequency Dynamics Using High-Speed 3D Laser Video Endoscopy

OBJECTIVE

To examine changes in lateral and vertical vibratory motion along the anterior, middle, and posterior sections of the vocal folds, as a function of vocal frequency variations.

METHODS

Absolute measurements of vocal fold surface dynamics from high-speed videoendoscopy with custom laser endoscope were made on 23 vocally healthy adults during sustained /i:/ production at 10%, 20%, and 80% of pitch range. The 3D parameters of amplitude (mm), maximum velocity opening/closing (mm/s), and mean velocity opening/closing (mm/s) were computed for the lateral and vertical vibratory motion along the anterior, middle, and posterior sections of the vocal folds. Linear mixed model analysis was conducted to evaluate the differences in (a) vocal frequency levels (high vs. normal vs. low pitch), (b) axis level (vertical vs. lateral), (c) position level (anterior vs. middle vs. posterior), and (d) gender differences (male vs. female).

RESULTS

Overall, the superior surface vertical motion of the vocal fold is greater compared with the lateral motion, especially in males. Along the superior surface, the mean and maximum closing velocities are greater posteriorly for low pitch. The location (anterior, middle, and posterior) along the superior surface is relevant only for vocal fold closing rather than opening, as the dynamics are different along the various locations.

CONCLUSIONS

The study highlights the significance of assessing the vertical motion of the superior surface of the vocal fold to understand the complex dynamics of voice production.

LEVEL OF EVIDENCE

NA Laryngoscope, 134:3267-3276, 2024.

Functional Analysis of Injectable Substance Treatment on Surgically Injured Rabbit Vocal Folds

OBJECTIVES

The objective of this study was to evaluate the efficacy of immediate injection treatments of dexamethasone, hyaluronic acid (HA)/gelatin (Ge) hydrogel and glycol-chitosan solution on the phonatory function of rabbit larynges at 42 days after surgical injury of the vocal folds, piloting a novel ex vivo phonatory functional analysis protocol.

METHODS

A modified microflap procedure was performed on the left vocal fold of 12 rabbits to induce an acute injury. Animals were randomized into one of four treatment groups with 0.1 mL injections of dexamethasone, HA/Ge hydrogel, glycol-chitosan or saline as control. The left mid vocal fold lamina propria was injected immediately following injury. The right vocal fold served as an uninjured control. Larynges were harvested at Day 42 after injection, then were subjected to airflow-bench evaluation. Acoustic, aerodynamic and laryngeal high-speed videoendoscopy (HSV) analyses were performed. HSV segments of the vibrating vocal folds were rated by three expert laryngologists. Six parameters related to vocal fold vibratory characteristics were evaluated on a Likert scale.

RESULTS

The fundamental frequency, one possible surrogate of vocal fold stiffness and scarring, was lower in the dexamethasone and HA/Ge hydrogel treatment groups compared to that of the saline control (411.52±11.63 Hz). The lowest fundamental frequency value was observed in the dexamethasone group (348.79±14.99 Hz). Expert visual ratings of the HSV segments indicated an overall positive outcome in the dexamethasone treatment group, though the impacts were below statistical significance.

CONCLUSION

Dexamethasone injections might be used as an adjunctive option for iatrogenic vocal fold scarring. An increased sample size, histological correlate, and experimental method improvements will be needed to confirm this finding. Results suggested a promising use of HSV and acoustic analysis techniques to identify and monitor post-surgical vocal fold repair and scarring, providing a useful tool for future studies of vocal fold scar treatments.

Looking for an Objective Parameter to Identify Early Vocal Dysfunctions in Healthy Perceived Singers

The finding of minimal laryngeal dysfunctions in professional voice users is essential to prevent the onset of organic vocal pathologies. The purpose of this study is to identify an objective parameter that supports the phoniatric evaluation in detecting minimal laryngeal dysfunctions in singers. 54 professional and non-professional singers have been evaluated with laryngostroboscopy, Multi-Dimensional Voice Program (MDVP), Dysphonia Severity Index (DSI), maximum phonation time (TMF), minimum intensity of sound emission (I-min), maximum frequency (F-max), voice handicap index (VHI), singing voice handicap index (SVHI), manual phonogram and audiometric examination. The SVHI of all the "healthy" singers was on average 23.7 ± 22.5, while that of the "dysfunctional" 20.9 ± 18. No statistically significant difference was found between the SVHI scores of the total of healthy singers compared to the scores of the dysfunctional ones on the VSL (p = 0.6). The between-group comparison of the means of individual parameter values of DSI, TMF, F-max, Jitter, Shimmer, NHR, and SPI was not statistically significant (respectively p = 0.315, 0.2, 0.18, 0.09, 0.2, 0.08, 0.3). The only parameter analyzed that was statistically significant was the I-min (p < 0.05). SVHI is a valid instrument for the evaluation after a therapy but in our experience, it is not useful in distinguishing healthy from dysfunctional patients. The minimum intensity of sound emission measured with the sound level meter (I-low2) resulted a reliable parameter to identify minimal laryngeal dysfunctions and a useful tool in supporting the phoniatric diagnostic-therapeutic process in singers.

The effect of the auditory signal on videolaryngostroboscopy ratings and interpretation

OBJECTIVE

The primary aim of this study was to examine the effect of the videolaryngostroboscopic auditory signal on videolaryngostroboscopy (VLS) ratings and interpretation in normophonic and dysphonic speakers.

STUDY DESIGN

Prospective repeated measures design METHOD: Eight speech-language pathologists evaluated rigid VLS exams obtained from 12 dysphonic speakers with vocal fold pathology and 4 normophonic speakers with normal VLS exams. VLS exams were evaluated with the auditory signal present and absent with a washout period between rating sessions. VLS measures were obtained using the Voice-vibratory Assessment of Laryngeal Imaging (VALI) and a 100mm visual analog scale (VAS). The effects of the auditory signal and its interaction with voice quality severity on 9 VLS ratings, diagnostic billing codes, and treatment recommendations were examined.

RESULTS

There was no effect of auditory information on VLS measures or overall severity of laryngeal function evaluated using the VAS (ps > 0.05). There was a main effect of auditory information and a significant interaction with voice quality severity for only one VLS measure (non-vibrating portion-left) evaluated using the VALI (P = 0.05). Post-hoc analysis for this rating showed significant increases (t-test adjusted P < 0.05) when voice quality severity was moderate-severe (M = 4.8%; SD = 1.65%) and auditory information was present. Agreement in individual clinician's selection of diagnostic codes (73%) and treatment recommendations (65.6%) when auditory cues were present and absent was moderate to high.

CONCLUSION

The presence of the videolaryngostroboscopic auditory signal had a minimal effect on VLS ratings, treatment recommendations, or diagnostic billing codes.

Determining Cutoff Point in Bahasa Malaysia Version of Voice Handicap Index-10 (mVHI-10)

OBJECTIVE

Determining the cutoff point on Bahasa Malaysia version of Voice Handicap Index (mVHI-10) questionnaire scores for distinguishing between dysphonic and normal voice samples.

STUDY DESIGN

A cross-sectional study was conducted in the tertiary hospital, Otorhinolaryngology-Head and Neck clinic.

METHODS

The study involved 205 subjects (105 in the dysphonia group; 100 in the normal group) with a complete database of flexible laryngoscopy/stroboscopy, voice recording, acoustic analysis, and mVHI-10 score. A sample with a discrepancy between subjective evaluation and acoustic analysis results was excluded from the study. Each classified dataset matched with the respective mVHI-10 questionnaire score. Finally, all the collected data were subjected to data analysis.

RESULTS

The best cutoff point for mVHI-10 was 7.5 by the receiver operating characteristic curve, with an area under the curve value of 0.997. Its sensitivity, specificity, positive predictive value, and negative predictive value were 92.4%, 100.0%, 100.0%, and 93.0%, respectively.

CONCLUSIONS

The best cutoff point for mVHI-10 is 7.5, as determined by stringent data evaluation and rigorous statistical analysis. With excellent diagnostic accuracy properties, it enhances the usage of the mVHI-10 questionnaire as an excellent screening tool. Nevertheless, we advocate multidimensional voice assessment for diagnostic purposes.

High-Speed Videoendoscopy Enhances the Objective Assessment of Glottic Organic Lesions: A Case-Control Study with Multivariable Data-Mining Model Development

The aim of the study was to utilize a quantitative assessment of the vibratory characteristics of vocal folds in diagnosing benign and malignant lesions of the glottis using high-speed videolaryngoscopy (HSV).

METHODS

Case-control study including 100 patients with unilateral vocal fold lesions in comparison to 38 normophonic subjects. Quantitative assessment with the determination of vocal fold oscillation parameters was performed based on HSV kymography. Machine-learning predictive models were developed and validated.

RESULTS

All calculated parameters differed significantly between healthy subjects and patients with organic lesions. The first predictive model distinguishing any organic lesion patients from healthy subjects reached an area under the curve (AUC) equal to 0.983 and presented with 89.3% accuracy, 97.0% sensitivity, and 71.4% specificity on the testing set. The second model identifying malignancy among organic lesions reached an AUC equal to 0.85 and presented with 80.6% accuracy, 100% sensitivity, and 71.1% specificity on the training set. Important predictive factors for the models were frequency perturbation measures.

CONCLUSIONS

The standard protocol for distinguishing between benign and malignant lesions continues to be clinical evaluation by an experienced ENT specialist and confirmed by histopathological examination. Our findings did suggest that advanced machine learning models, which consider the complex interactions present in HSV data, could potentially indicate a heightened risk of malignancy. Therefore, this technology could prove pivotal in aiding in early cancer detection, thereby emphasizing the need for further investigation and validation.

Non-Linear Image Distortions in Flexible Fiberoptic Endoscopes and their Effects on Calibrated Horizontal Measurements Using High-Speed Videoendoscopy

Laryngeal images obtained via high-speed videoendoscopy are an invaluable source of information for the advancement of voice science because they can capture the true cycle-to-cycle vibratory characteristics of the vocal folds in addition to the transient behaviors of the phonatory mechanism, such as onset, offset, and breaks. This information is obtained through relating the spatial and temporal features from acquired images using objective measurements or subjective assessments. While these images are calibrated temporally, a great challenge is the lack of spatial calibration. Recently, a laser-projection system allowing for spatial calibration was developed. However, various sources of optical distortions deviate the images from reflecting the reality. The main purpose of this study was to evaluate the effect of the fiberoptic flexible endoscope distortions on the calibration of images acquired by the laser-projection system. Specifically, it is shown that two sources of nonlinear distortions could deviate captured images from reality. The first distortion stems from the wide-angle lens used in flexible endoscopes. It is shown that endoscopic images have a significantly higher spatial resolution in the center of the field of view than in its periphery. The difference between the two could lead to as high as 26.4% error in calibrated horizontal measurements. The second distortion stems from variation in the imaging angle. It is shown that the disparity between spatial resolution in the center and periphery of endoscopic images increases as the imaging angle deviates from the perpendicular position. Furthermore, it is shown that when the imaging angle varies, the symmetry of the distortion is also affected significantly. The combined distortions could lead to calibrated horizontal measurement errors as high as 65.7%. The implications of the findings on objective measurements and subjective visual assessments are discussed. These findings can contribute to the refinement of the methods for clinical assessment of voice disorders. Considering that the studied phenomena are due to optical principles, the findings of this study, especially those related to the effects of the imaging angle, can provide further insights regarding other endoscopic instruments (eg, distal-chip and rigid endoscopes) and procedures (eg, gastroendoscopy and colonoscopy).

Glottic Staphylococcus aureus in a patient with systemic lupus erythematosus: videolaryngostroboscopic characteristics

Systemic lupus erythematous (SLE) is an autoimmune disease commonly treated with steroid which leads to immunosuppression and increased susceptibility to infection. Chronic laryngitis with whitish lesion on the true vocal fold in SLE may be caused by opportunistic organisms, such as tuberculous, fungal and Staphylococcus aureus infections. Videolaryngostroboscopy may be helpful in leading to the diagnosis and optimum treatment of glottic S. aureus A woman in her 40s with SLE presented with progressively worsening hoarseness for 2 months, accompanied by sore throat and odynophagia. Videoendoscopy showed erythematous and oedematous bilateral vocal fold with whitish lesion seen at the edge of middle one-third while the videolaryngostroboscopic evaluation showed there was severe asymmetry of the bilateral vocal folds, with severely reduced amplitude during phonation where the vocal cords were not vibrating, aperiodic vibratory cycles and 'always open', incomplete closure of vocal cord pattern. Later, endolaryngeal microsurgery and biopsy of the lesion confirmed of glottic S. aureus Her symptoms and followed up videolaryngostroboscopy showed resolution to normal findings after 6 weeks of cloxacillin. S. aureus infection of the glottis is a differential diagnosis in a chronic laryngitis with leucoplakic lesion in an immunosuppressive patient. Videolaryngostroboscopy has an important role in diagnosis, evaluation and treatment decision.

Laryngology Quality of Life Questionnaire Associations: Towards Reducing Survey Burden

OBJECTIVES

Outcomes in laryngology focus primarily on patient reported outcome measures (PROMs). The increasing number of questionnaires may lead to survey fatigue. We sought to determine the relationship between the newest questionnaire, Laryngopharyngeal Universal Measure of Perceived Sensation (LUMP), and other laryngology PROMs.

STUDY DESIGN

Cross-sectional study.

METHODS

Patients undergoing laryngology multidisciplinary evaluation prospectively completed laryngology questionnaires. Average summed scores between standard laryngology PROMs (ie, VHI-10, RSI, DI, CSI, EAT-10) and LUMP were compared. Expert consensus panel identified the most clinically relevant statements which were then compared to LUMP summed scores, in increasingly additive fashion.

RESULTS

Four hundred eighty patients (259 female) were assessed. Average age was 57.1 ± 17.7 years. Intraclass correlation coefficient (ICC) for each PROM in comparison to LUMP ranged from moderate to poor correlation: 0.64 (RSI), 0.55 (EAT-10), 0.50 (DI), 0.48 (CSI), and 0.34 (VHI-10). ICC for combinations of the five most clinically relevant individual items ranged from 0.29-0.53.

CONCLUSIONS

Patients with self-reported globus had statistically significantly higher scores across all PROMs. RSI had moderate correlation with LUMP, and the five selected expert consensus items demonstrated weaker correlation. While RSI may serve as a moderately selective clinical proxy for the LUMP questionnaire, LUMP remains a validated tool with increased specificity for quantification of globus which may be especially important in the research setting. There is continued question about the need for multiple laryngologic PROMs to evaluate patient complaints, and survey reduction remains an area of interest to decrease respondent fatigue, optimize patient care, and quantify interventional success.

LEVEL OF EVIDENCE

4 Laryngoscope, 131:1561-1565, 2021.

Laryngeal Electromyography-Guided Hyaluronic Acid Vocal Fold Injections for Glottic Insufficiency

OBJECTIVES

To assess voice outcomes using the novel technique of in-office laryngeal electromyography-guided vocal fold injections (LEVFI) with hyaluronic acid to treat glottal insufficiency. Secondary objectives included determining the complication/completion rates and if any factors were associated with improved voice outcomes.

METHODS

Retrospective review of patients who received their first LEVFI from August 2017 to December 2018. Three- and six-month voice outcomes were assessed. Outcomes included voice handicap index-10 (VHI-10), maximum phonation time (MPT), perceptual analysis of voice (GRBAS), fundamental frequency, and stroboscopy.

RESULTS

Of the 121 eligible patients (55.4% male, age 63.7 years), 94 (77.7%) had complete 3-month data and 59 (48.8%) had complete 6-month data. VHI-10 was significantly improved from 25.7 ± 7.5 to 20.9 ± 10.9 at 3 months (P < .001) and to 19.1 ± 11.5 at 6 months (P < .001). MPT improved from 6.2 ± 5.4 seconds to 9.4 ± 7.1 seconds at 3 months (P < .001) and to 11.3 ± 8.2 seconds at 6 months (P < .001). GRBAS was improved in 74.8% of patients ([65.2, 82.8] 95% CI) at 3 months and 80.8% ([69.9, 89.1]) 95% CI) at 6 months. Stroboscopy showed a glottic gap improvement in 74.8% of patients ([65.8, 82.4] 95% CI) at 3 months and in 80.3% ([65.9, 88.5] 95% CI) at 6 months. Fundamental frequency was unchanged, as expected. Multivariate analysis reported that no factors were associated with better voice outcomes. Overall, 177/181 (97.8%) injections were completed. There were no complications.

CONCLUSION

In-office LEVFI is an effective, novel technique to treat glottic insufficiency with improved voice outcomes, high completion rate, and no significant complications.

Vocal Hygiene in Collegiate Singers-Does Formal Training Relate to Practices?

BACKGROUND

Vocal hygiene is vitally important for protecting vocal quality and promoting vocal longevity. It includes adequate hydration, avoidance of environmental irritants, and refraining from phonotraumatic behaviors such as screaming, excessive talking, and throat clearing. Formal singing training in addition to enhancing singing techniques, is also assumed to promote good vocal hygiene. Consequently, we investigated whether collegiate singers with formal training are more likely to practice good vocal hygiene habits than untrained collegiate singers.

METHODS

We completed a prospective cohort study, where collegiate singers at Stanford University were voluntarily enrolled in an annual vocal health clinic. Full laryngeal exams were performed and demographic information, formal vocal training status, and information on vocal hygiene habits were obtained through questionnaires. The results were then analyzed by grouping singers as "untrained" if less than 1 year of formal training, and "trained" if greater than a year.

RESULTS

A total of 82 singers were included for analysis, with 49 (59.8%) having greater than one year of formal training. Trained singers were more likely to employ a primary musical singing style of classical or operatic singing compared to untrained singers who were more likely to utilize "R&B" (P < 0.001). No significant differences were found between groups for hydration practices (P = 0.20), caffeine consumption (P = 0.73), warm up practices (P = 0.08), and phonotraumatic behaviors. Alcohol consumption, smoking tobacco, marijuana, e-cigarette usage was similar between groups. Overall, 11% of our sample reported intermittent less than daily marijuana use, with one singer reporting daily consumption. None of the singers in this sample used e-cigarettes. These rates are noticeably lower than the agematched United States population. Perceptions of cigarettes, marijuana, electronic cigarettes, alcohol, and caffeine were also the same between groups, with the vast majority of singers perceiving these agents as harmful to the voice (64%-100% depending on the agent). No laryngeal pathology was identified during laryngeal examination of any singers.

CONCLUSIONS

Vocal hygiene habits are similar between trained and untrained collegiate singers. This likely relates to a desire for vocal longevity irrespective of prior training. This may dispel the long-held assumption that formal training was necessary to develop good vocal habits. We do however, present a very homogenous, highly educated sample of collegiate singers from Stanford University, having significantly less at-risk behavior than their aged-matched counterparts in the general US population. A lack of laryngeal pathology despite extensive vocal demands may also be reflective of good vocal hygiene habits.

Study of Pre and Post Operative Videostroboscopic Evaluation of Benign Vocal Cord Lesions

To determine pre and postoperative vocal fold vibratory changes using videostroboscopy (VS) and effect of surgery on functional, physical and emotional levels of voice using voice handicap index (VHI). To determine correlation between VHI and VS in patients with benign vocal fold pathology. This is a prospective study done at Pushpagiri Medical College. 40 patients in the age group of 14-75 years who presented with complaints of voice change were included. VS and VHI of patients done preoperatively in 40 patients. Patients were re-evaluated postoperatively at 1 month by VHI and VS. All patients underwent microlaryngoscopic excision of the benign vocal cord lesion with biopsy under GA in the conventional manner. One month postoperatively, these patients were evaluated by VS and VHI and the findings noted. There was statistically significant improvement in the stroboscopy ratings and VHI scores post operatively (p < 0.0001). The mucosal wave was diminished or absent in 100% of the studied TVC cysts and present in approximately 60% of vocal polyps. There was no significant correlation found between preoperative VHI scores and stroboscopy ratings except for mucosal waves. Whereas there was significant correlation noted between the VHI subscales and total scores with stroboscopic scores postoperatively except for symmetry. All but 6 patients in this study benefitted from surgery and 85% had a normal voice post-operatively. Pre and post operative assessment of patients with benign vocal fold lesions by stroboscopy and VHI is a useful way to determine the degree of improvement following surgery.

Outcome Analysis of Microlaryngeal Surgery for Benign Lesions of Vocal Cord Using Videostroboscopy and Voice Handicap Index

Benign vocal cord mass lesions are common causes of dysphonia which are often surgically correctable. They include lesions like vocal polyps, vocal cysts, vocal nodules and Reinke's edema. A prospective study of 30 patients was carried out at SMS medical college and hospital between April 2014 to November 2015 after institutional ethical committee clearance. The purpose of our study was to evaluate outcome of microlaryngeal surgery for benign lesions of vocal cord using videostroboscopy and voice handicap index. All cases between the age group 15-60 years with clinical evidence of benign lesions of vocal cord were included in study. Preoperative amplitude, mucosal wave, glottic closure was seen by videostroboscopy and subjective assessment of severity of handicap in voice was assessed by set of questionnaire using voice handicap index (Jacobson et al. in Am J Speech Lang Pathol 6: 66-70, 1997). Postoperative follow up was done at 3rd week and 10th week, and outcome of microlaryngeal surgery was assessed using videostroboscope and voice handicap index. At the end of study data was compiled systemically and analysed using paired 't' test and Chi square test. Our study observed statistically significant improvement in amplitude and mucosal wave and glottic closure. Subjective improvement in perception of severity of handicap in voice was analysed by voice handicap index which shows statistically significant data. Overall our study conclude microlaryngeal surgery as an effective way for improvement in speech parameters, that can be assessed by use of videostroboscopy and voice handicap index.

Does the accuracy of case history affect interpretation of videolaryngostroboscopic exams?

OBJECTIVE

To determine the effect of initial diagnostic hypotheses on clinicians' 1) detection and perceived severity of abnormalities, and 2) clinical impressions and treatment recommendations for individuals with and without voice disorders following interpretation of videolaryngostroboscopy (VLS).

METHODS

Thirty-two experienced speech-language pathologists and otolaryngologists specializing in voice disorders read case histories prior to interpreting exams. Case histories suggested specific accurate or inaccurate laryngeal diagnoses, or a control scenario that suggested a normal larynx. The effects of the accuracy of case histories on perceived severity of associated visual-perceptual parameters, clinical impressions, and treatment recommendations were examined.

RESULTS

Significant increases in perceived severity of posterior laryngeal appearance (P < 0.05) and mucosal wave (P < 0.02) were observed when these abnormalities were suggested by case histories. Overall agreement with clinical impressions improved from 49% to 72% when the case history was consistent with the examination. Case histories (accurate and inaccurate) indicating voice symptoms predicted recommendations for treatment above and beyond that of VLS presentation alone, P < 0.001.

CONCLUSION

Case histories suggesting specific abnormalities significantly affected severity ratings for two of three associated visual-perceptual parameters selected as primary outcome measures. Accurate case histories suggesting specific abnormalities increased the probability of detection and perceived severity. Inaccurate case histories led to false-positive findings and failures to detect abnormalities or to interpret them as less severe. Case histories affected visual-perceptual judgments and contributed to decisions about clinical impressions and treatment.

LEVEL OF EVIDENCE

2b Laryngoscope, 130:718-725, 2020.

Laryngeal stroboscopy-Normative values for amplitude, open quotient, asymmetry and phase difference in young adults

OBJECTIVE

To provide the normative values for laryngeal stroboscopy (LS) concerning amplitude, open quotient, asymmetry and phase difference in healthy, young subjects.

STUDY DESIGN

Prospective case-control study.

SETTING

Patients treated at a single institute.

METHODS

A total of 68 healthy subjects were included in the study (35 women, 33 men), aged 18-35 years. After obtaining LS recordings, image processing was performed to attain parameters of vocal fold vibration.

RESULTS

In women, the location of the maximum vibration amplitude is approximately in the 1/3 posterior part of the glottis, while in men, the location is moved to the glottis centre. In males, the relative amplitude vibration of the vocal folds in the 1/3 anterior part of the glottis was significantly higher than in females (P = 0.029). Women showed significantly higher open quotients (OQ) at the posterior part of the glottis than the male subjects (P < 0.001) and men presented significantly higher OQ at the anterior part of the glottis than the females (P < 0.001). The average OQ values for both sexes were almost the same. Females showed significantly higher relative glottal gap area (P = 0.044). Women presented a significantly lower amplitude asymmetry than men (P = 0.002). The weighted absolute left-right phase difference reached up to 24° and remained insignificantly higher in the men than the women (P = 0.142).

CONCLUSIONS

The study provides normative values for LS in young adults for the measurement of therapy outcomes in patients with voice disorders and realisation of evidence-based medicine. The LS parametrisation is easy to perform in clinical practice.

Cross-cultural Adaptation and Validation of the Greek Voice Handicap Index-10 (GVHI-10) With Additional Receiver Operating Characteristic Analysis

OBJECTIVE(S)

The use of subjective evaluation tools are proven useful and of high clinical value in the case of voice disordered population. For that type of evaluation, self-assessment questionnaires about the severity of the voice like Voice Handicap Index-30 (VHI-30) have been developed. The VHI-30 is the most studied tool which includes psychometrically robustness while guiding physician's therapeutic decision making. Additionally, a valid abbreviated version of VHI-30 was developed for the first time in the Greek Language which is named as Greek Voice Handicap Index-10 (GVHI-10). Consequently, the aim of our study was to validate the proposed version of the VHI-10.

METHODS

Ninety nondysphonic individuals and 90 dysphonic patients were classified by Otolaryngologists and Speech Language Pathologists. The study's subjects were evaluated with endoscopy and stroboscopy. Also, they were administrated the GVHI-30 and the translated version of the Voice Evaluation Template (VEF). The GVHI-10 was extracted by the Greek version of VHI-30.

RESULTS

The group with voice disorders exhibited higher statistical significance in all GVHI-10 scores compared to those of the control group. The GVHI-10 showed a high internal consistency (Cronbach's a = 0.915 and split-half reliability coefficient equal to 0.86), good sensitivity compared to Greek VHI-30 (r = 0.764, P = 0.000) and intraclass correlation. A total cut-off point equal to 6.50 (AUC: 0.964; P < 0.001) was also calculated.

CONCLUSIONS

The proposed version of GVHI-10 distinguished the perceived levels of voice between dysphonic and nondysphonic groups and between different voice disordered populations. The GVHI-10 is shown to be clinically valid and sensitive exhibiting high reliability.

Immediate selective laryngeal reinnervation in vagal paraganglioma patients

OBJECTIVE

This prospective case series aimed to present the outcomes of immediate selective laryngeal reinnervation.

METHODS

Two middle-aged women with vagal paraganglioma undergoing an excision operation underwent immediate selective laryngeal reinnervation using the phrenic nerve and ansa cervicalis as the donor nerve. Multidimensional outcome measures were employed pre-operatively, and at 1, 6 and 12 months post-operatively.

RESULTS

The voice handicap index-10 score improved from 23 (patient 1) and 18 (patient 2) at 1 month post-operation, to 5 (patient 1) and 1 (patient 2) at 12 months. The Eating Assessment Tool 10 score improved from 20 (patient 1) and 24 (patient 2) at 1 month post-operation, to 3 (patient 1) and 1 (patient 2) at 12 months. There was slight vocal fold abduction observed in patient one and no obvious abduction in patient two.

CONCLUSION

Selective reinnervation is safe to perform following vagal paraganglioma excision conducted on the same side. Voice and swallowing improvements were demonstrated, but no significant vocal fold abduction was achieved.

Recommended Protocols for Instrumental Assessment of Voice: American Speech-Language-Hearing Association Expert Panel to Develop a Protocol for Instrumental Assessment of Vocal Function

PURPOSE

The aim of this study was to recommend protocols for instrumental assessment of voice production in the areas of laryngeal endoscopic imaging, acoustic analyses, and aerodynamic procedures, which will (a) improve the evidence for voice assessment measures, (b) enable valid comparisons of assessment results within and across clients and facilities, and (c) facilitate the evaluation of treatment efficacy.

METHOD

Existing evidence was combined with expert consensus in areas with a lack of evidence. In addition, a survey of clinicians and a peer review of an initial version of the protocol via VoiceServe and the American Speech-Language-Hearing Association's Special Interest Group 3 (Voice and Voice Disorders) Community were used to create the recommendations for the final protocols.

RESULTS

The protocols include recommendations regarding technical specifications for data acquisition, voice and speech tasks, analysis methods, and reporting of results for instrumental evaluation of voice production in the areas of laryngeal endoscopic imaging, acoustics, and aerodynamics.

CONCLUSION

The recommended protocols for instrumental assessment of voice using laryngeal endoscopic imaging, acoustic, and aerodynamic methods will enable clinicians and researchers to collect a uniform set of valid and reliable measures that can be compared across assessments, clients, and facilities.

Proposal of a form for the collection of videolaryngostroboscopy basic findings

Videolaryngostroboscopy is a useful investigation required for a correct diagnosis of laryngeal diseases and voice disorders. We present a form for the collection of basic laryngostroboscopic findings, which provides for the evaluation of the classical six parameters codified by Hirano (symmetry and periodicity of glottic vibration, glottic closure, profile of vocal fold edge, amplitude of vocal fold vibration, mucosal wave) and six other parameters which we have included in the form for an essential and complete laryngostroboscopic evaluation (supraglottic framework behaviour, seat of phonatory vibration, vocal fold morphology and motility, level of the vocal fold, stops of vocal fold mucosa vibration). This form was created in 2002 during the elaboration of the protocol for the assessment of dysphonia of the Italian Society of Phoniatrics and Logopedics, which follows the guidelines of the European Laryngological Society published in 2001. We used this form for 15 years in our daily laryngological practice with great satisfaction. We propose a more detailed version of this form, which provides for drawings which show the various videolaryngostroboscopic findings, helping the laryngologist in the collection of videolaryngostroboscopic examination basic findings.

The value of narrow band imaging combined with stroboscopy for the detection of applanate indiscernible early-stage vocal cord cancer

BACKGROUND

Narrow band imaging (NBI) and stroboscopy are non-invasive techniques to detect the malignant lesions of the vocal cord. This study was to assess the diagnostic value of combined endoscopic analysis in the applanate indiscernible early-stage vocal cord cancer.

METHODS

A total of 110 patients with 160 suspicious vocal cord malignant lesions were included in this retrospective study. Stroboscopy was immediately performed after NBI and white light endoscopy (WLE) were performed in all patients. Excisional biopsy was performed to examine histopathology examination.

RESULTS

We found that the diagnostic specificity and PPV were higher in the NBI and WLE combined with stroboscopy group than in the NBI and WLE group without stroboscopy (88.9% vs 72.5%, 88.4% vs 60.9%). However, the diagnostic sensitivity was not significantly different in those two groups (69.3% vs 67.7%).

CONCLUSION

NBI and WLE combined with stroboscopy is a promising method to detect early-stage vocal cord cancer with the advantage of clinical feasibility and diagnostic specificity.

Reliability of High-speed Videoendoscopic Ratings of Essential Voice Tremor and Adductor Spasmodic Dysphonia

OBJECTIVES

The main objectives of this study were to (1) examine intrarater and inter-rater reliabilities in perceptual ratings of vocal fold vibratory patterns and supraglottic characteristics for essential vocal tremor and adductor spasmodic dysphonia (AdSD) using high-speed videoendoscopy (HSV), and (2) to investigate the specificity of the parameters in differentiating these two voice disorders.

METHODS

HSV recordings of 34 cases diagnosed with essential vocal tremor, AdSD, or AdSD with vocal tremor were evaluated blindly by two voice speech pathologists. The two raters examined all HSV video segments twice across nine supraglottic and vocal fold vibratory characteristics for inter-rater and intrarater reliabilities. A separate consensus rating was then developed, with the results analyzed to explore differentiation.

RESULTS

Raters demonstrated moderate intrarater reliability with mean Spearman's rho correlation coefficients of 0.68 (rater 1) and 0.73 (rater 2). Moderate inter-rater reliability for the two raters was seen across all parameters with a mean Cohen's kappa coefficient of 0.51. Raters showed higher intrarater and inter-rater reliabilities for supraglottic parameters. Only the presence of tremor differentiated between the two voice disorders in cases with a consistent diagnosis.

CONCLUSIONS

The high level of concomitance between vocal tremor and AdSD may affect subjective perceptual analysis of supraglottic and vocal fold vibratory patterns. Results indicate similar global involvement of supraglottic laryngeal structures for both vocal tremor and AdSD.

Observer Agreement for Measurements in Videolaryngostroboscopy

OBJECTIVE

This study evaluated the levels of intraobserver and interobserver agreement for measurements of visuoperceptual variables in videolaryngostroboscopic examinations and compared the observers' behavior during independent versus consensus panel rating.

STUDY DESIGN

This is a retrospective study.

SETTING

This study was conducted in a single-center tertiary care facility.

PARTICIPANTS

Sixty-four patients with dysphonia of heterogeneous etiology were included.

EXPOSURE

All subjects underwent a standardized videolaryngostroboscopic examination.

MAIN OUTCOME AND MEASURES

Two experienced and trained observers scored exactly the same examinations, first independently and then on a consensus panel. Specific visuoperceptual variables and the clinical diagnosis (as recommended by the Committee on Phoniatrics and the Phonosurgery Committee of the European Laryngological Society and advised by the American Speech-Language-Hearing Association) were scored. Descriptive and kappa statistics were used.

RESULTS

In general, intraobserver agreement was better than agreement between observers for measurements of several variables. The intrapanel observer agreement levels were slightly higher than the intraobserver agreement levels on the independent rating task. When rating on the consensus panel, the observers deviated considerably from the scores they had previously given on the independent rating task.

CONCLUSION AND RELEVANCE

Observer agreement in videolaryngostroboscopic assessment has important implications not only for the diagnosis and treatment of dysphonic patients but also for the interpretation of the results of scientific studies using videolaryngostroboscopic outcome parameters. The identification of factors that can influence the levels of observer agreement can provide a better understanding of the rating process and its limitations. The results of this study suggest that future research could achieve better agreement levels by rating the visuoperceptual variables in a panel setting.

Parameters and Scales Used to Assess and Report Findings From Stroboscopy: A Systematic Review

OBJECTIVE

Laryngeal endoscopy with stroboscopy, a critical component of the assessment of voice disorders, is rarely used as a treatment outcome measure in the scientific literature. We hypothesized that this is because of the lack of a widely used standardized, validated, and reliable method to assess and report laryngeal anatomy and physiology, and undertook a systematic literature review to determine the extent of the inconsistencies of the parameters and scales used in voice treatment outcome studies.

STUDY DESIGN

Systematic literature review.

METHODS

We searched PubMed, Ovid, and Cochrane for studies where laryngeal endoscopy with stroboscopy was used as a treatment outcome measure with search terms representing "stroboscopy" and "treatment" guided by Preferred Reporting Items for Systematic Reviews and Meta-Analyses statement standards.

RESULTS

In the 62 included articles, we identified 141 terms representing 49 different parameters, which were further classified into 20 broad categories. The six most common parameters were magnitude of glottal gap, mucosal wave amplitude, location or shape of glottal gap, regularity of vibration, phase symmetry, and presence and size of specific lesions. Parameters were assessed on scales ranging from binary to 100 points. The number of scales used for each parameter varied from 1 to 24, with an average of four different scales per parameter.

CONCLUSIONS

There is a lack of agreement in the scientific literature regarding which parameters should be assessed to measure voice treatment outcomes and which terms and scales should be used for each parameter. This greatly diminishes comparison and clinical implementation of the results of treatment outcomes research in voice disorders. We highlight a previously published tool and recommend it for future use in research and clinical settings.

endoscope-i: an innovation in mobile endoscopic technology transforming the delivery of patient care in otolaryngology

INTRODUCTION

Digital and mobile device technology in healthcare is a growing market. The introduction of the endoscope-i, the world's first endoscopic mobile imaging system, allows the acquisition of high definition images of the ear, nose and throat (ENT). The system combines the e-i Pro camera app with a bespoke engineered endoscope-i adaptor which fits securely onto the iPhone or iPod touch. Endoscopic examination forms a salient aspect of the ENT work-up. The endoscope-i therefore provides a mobile and compact alternative to the existing bulky endoscopic systems currently in use which often restrict the clinician to the clinic setting. Areas covered: This article gives a detailed overview of the endoscope-i system together with its applications. A review and comparison of alternative devices on the market offering smartphone adapted endoscopic viewing systems is also presented. Expert commentary: The endoscope-i fulfils unmet needs by providing a compact, highly portable, simple to use endoscopic viewing system which is cost-effective and which makes use of smartphone technology most clinicians have in their pocket. The system allows real-time feedback to the patient and has the potential to transform the way that healthcare is delivered in ENT as well as having applications further afield.

Intra- and Inter-database Study for Arabic, English, and German Databases: Do Conventional Speech Features Detect Voice Pathology?

A large population around the world has voice complications. Various approaches for subjective and objective evaluations have been suggested in the literature. The subjective approach strongly depends on the experience and area of expertise of a clinician, and human error cannot be neglected. On the other hand, the objective or automatic approach is noninvasive. Automatic developed systems can provide complementary information that may be helpful for a clinician in the early screening of a voice disorder. At the same time, automatic systems can be deployed in remote areas where a general practitioner can use them and may refer the patient to a specialist to avoid complications that may be life threatening. Many automatic systems for disorder detection have been developed by applying different types of conventional speech features such as the linear prediction coefficients, linear prediction cepstral coefficients, and Mel-frequency cepstral coefficients (MFCCs). This study aims to ascertain whether conventional speech features detect voice pathology reliably, and whether they can be correlated with voice quality. To investigate this, an automatic detection system based on MFCC was developed, and three different voice disorder databases were used in this study. The experimental results suggest that the accuracy of the MFCC-based system varies from database to database. The detection rate for the intra-database ranges from 72% to 95%, and that for the inter-database is from 47% to 82%. The results conclude that conventional speech features are not correlated with voice, and hence are not reliable in pathology detection.

Preliminary Evaluation of Stroboscopy System Using Multiple Light Sources for Observation of Pathological Vocal Fold Oscillatory Pattern

Objectives:

Laryngostroboscopy is used to check the oscillatory patterns of the vocal folds. However, the use of one single flash timing cannot give a clear view of abnormal vocal fold oscillations that have multiple fundamental frequencies. Visualization of such complex vocal fold movements will be helpful in the diagnosis of diplophonia, a pathological condition in which the vocal folds produce multiple tones at the same time.

Methods:

We developed a new stroboscopy-based technique using multiple light-emitting diodes (LEDs) and image analysis. Specific flash timings for each LED, suitable for accurate visualization, were determined on a computer according to an algorithm based on frequency analysis. The image analysis extracted the necessary parts of the captured images to yield a clear slow-motion view of the oscillations. The series of visualization procedures took advantage of the narrow-spectrum light property of LEDs, thereby yielding a degradation-free picture.

Results:

Feasibility tests using a mechanical vocal fold model demonstrated that this computer-assisted system allows observation of the pathological oscillatory patterns as one single video. They would not be clearly visualized by conventional stroboscopy.

Conclusions:

Because of its relatively simple use and inexpensive construction, the proposed technique can become one potential option for clinical assessment of pathological vocal fold oscillations.

Vocal fold augmentation with calcium hydroxylapatite (CaHA)

Objectives

Evaluate the effectiveness of CaHA injection for patients with glottal incompetence.

Methods

Multi-center, open-label, prospective clinical study with each patient serving as his/her own control. Voice-related outcome measures were collected for pre-injection and 1, 3, and 6 months.

Results

Sixty-eight patients were available for evaluation. Fifty percent of the injection procedures were done in office. Fifty-seven percent were diagnosed with unilateral paralysis and 42% with glottal incompetence with mobile vocal folds. Patient satisfaction 6 months post showed 56% had significantly improved voice and 38% reported moderately improved voice. Paired t tests from baseline to 6 months showed significant improvements on the VHI and VAS (vocal effort), CAPE-V judgments of voice severity and videoendostroboscopy ratings of glottal closure, and objective voice measures of glottal closure (MPT and S:Z ratio).

Conclusions

Preliminary results in this large cohort of patients demonstrate excellent clinical results.

Extension and Application of High-Speed Digital Imaging Analysis Via Spatiotemporal Correlation and Eigenmode Analysis of Vocal Fold Vibration Before and After Polyp Excision

OBJECTIVES/HYPOTHESIS

To evaluate the spatiotemporal correlation of vocal fold vibration using eigenmode analysis before and after polyp removal and explore the potential clinical relevance of spatiotemporal analysis of correlation length and entropy as quantitative voice parameters. We hypothesized that increased order in the vibrating signal after surgical intervention would decrease the eigenmode-based entropy and increase correlation length.

STUDY DESIGN

Prospective case series.

METHODS

Forty subjects (23 males, 17 females) with unilateral (n = 24) or bilateral (n = 16) polyps underwent polyp removal. High-speed videoendoscopy was performed preoperatively and 2 weeks postoperatively. Spatiotemporal analysis was performed to determine entropy, quantification of signal disorder, correlation length, size, and spatially ordered structure of vocal fold vibration in comparison to full spatial consistency. The signal analyzed consists of the vibratory pattern in space and time derived from the high-speed video glottal area contour.

RESULTS

Entropy decreased (Z = -3.871, P < .001) and correlation length increased (t = -8.913, P < .001) following polyp excision. The intraclass correlation coefficients (ICC) for correlation length and entropy were 0.84 and 0.93.

CONCLUSION

Correlation length and entropy are sensitive to mass lesions. These parameters could potentially be used to augment subjective visualization after polyp excision when evaluating procedural efficacy.

Investigating the Effects of Smoking on Young Adult Male Voice by Using Multidimensional Methods

OBJECTIVES

Smoking is one of the most common harmful habits in the world, especially common among young adult male population in Turkey. The purpose of this study was to evaluate the effect of smoking on the young adults' male voice using multidimensional voice assessment methods.

STUDY DESIGN

This is a case-control study.

METHODS

The study included 109 young adult men, 51 nonsmokers and 58 smokers between the ages of 20 and 34 years. The voice evaluation protocol consisted of voice handicap index (VHI), maximum phonation time (MPT), and perceptual, acoustic, and videostroboscopic analyses.

RESULTS

A statistically significant increase for physical, physiological, and total scores of VHI was found in smokers group (P < 0.05). MPT showed significantly lower values among smokers (P < 0.05). There were no significant changes in perceptual analysis of voice samples between smoker and nonsmoker groups. There were no significant changes in any of the acoustic parameters between smoker and nonsmoker groups. Results of videostroboscopic analysis showed significant relationships between smoking and increased vocal fold erythema (P < 0.05). In addition, significantly asymmetry, amplitude, and periodicity abnormality of vocal fold movements were observed in smoker group during phonation (P < 0.05).

CONCLUSIONS

The results of this study indicate that observable signs of laryngeal irritation and disturbed phonatory physiology occur even in young adults with relatively brief smoking habits. Subjective symptoms of smoking on voice appear to occur earlier than objective findings.

A Preliminary Quantitative Comparison of Vibratory Amplitude Using Rigid and Flexible Stroboscopic Assessment

STUDY OBJECTIVE

The purpose of this study was to establish preliminary, quantitative data on amplitude of vibration during stroboscopic assessment in healthy speakers with normal voice characteristics. Amplitude of vocal fold vibration is a core physiological parameter used in diagnosing voice disorders, yet quantitative data are lacking to guide the determination of what constitutes normal vibratory amplitude.

METHODS/STUDY DESIGN

Eleven participants were assessed during sustained vowel production using rigid and flexible endoscopy with stroboscopy. Still images were extracted from digital recordings of a sustained /i/ produced at a comfortable pitch and loudness, with F0 controlled so that levels were within ±15% of each participant's comfortable mean level as determined from connected speech. Glottal width (GW), true vocal fold (TVF) length, and TVF width were measured from still frames representing the maximum open phase of the vibratory cycle. To control for anatomic and magnification differences across participants, GW was normalized to TVF length. GW as a ratio of TVF width was also computed for comparison with prior studies.

RESULTS

Mean values and standard deviations were computed for the normalized measures. Paired t tests showed no significant differences between rigid and flexible endoscopy methods. Interrater and intrarater reliability values for raw measurements were found to be high (0.89-0.99).

CONCLUSIONS

These preliminary quantitative data may be helpful in determining normality or abnormality of vocal fold vibration. Results indicate that quantified amplitude of vibration is similar between endoscopic methods, a clinically relevant finding for individuals performing and interpreting stroboscopic assessments.

High-speed video or video stroboscopy in adolescents: which sheds more light?

OBJECTIVE

The primary objective of this study was to compare the utility of high-speed video (HSV) to videostroboscopy (VS) in the assessment of adolescents with normal and abnormal larynges. A secondary objective was to evaluate the ease of assessment of adolescents with HSV.

STUDY DESIGN

Case series with chart review.

SETTING

Tertiary academic health care center.

SUBJECTS AND METHODS

This study involved a retrospective review of recordings of 7 adolescents assessed with both HSV and VS. The 14 recordings were randomized and presented to 4 groups of blinded evaluators: 2 fellowship-trained laryngologists, 2 speech language pathologists (SLP) with multiyear experience working in a voice clinic, 2 pediatric otolaryngologists, and 2 otolaryngology residents. Raters were asked to evaluate the videos using a standardized scoring tool. Raters also completed a questionnaire assessing their opinion of the HSV and VS recordings.

RESULTS

Evaluators required more time to complete their assessment of VS recordings (2.95 min ± 2.41 min) than HSV recordings (2.31 min ± 1.92 min) (P = .004). There was no difference in ease of evaluation (P = .878) or diagnostic accuracy within evaluator groups by recording modality (P = .5). The overall agreement between VS and HSV was moderate (kappa [SE] = 0.446 [0.029]). The debrief questionnaire revealed that 5 of 8 (62.5%) preferred VS to HSV.

CONCLUSION

This is the first comparative study between HSV and VS in patients under 18 years of age. HSV permitted faster evaluation than VS, but there was no difference in diagnostic accuracy between the 2 modalities. The evaluators preferred VS to HSV.

Rater methodology for stroboscopy: a systematic review

OBJECTIVES

Laryngeal endoscopy with stroboscopy (LES) remains the clinical gold standard for assessing vocal fold function. LES is used to evaluate the efficacy of voice treatments in research studies and clinical practice. LES as a voice treatment outcome tool is only as good as the clinician interpreting the recordings. Research using LES as a treatment outcome measure should be evaluated based on rater methodology and reliability. The purpose of this literature review was to evaluate the rater-related methodology from studies that use stroboscopic findings as voice treatment outcome measures.

STUDY DESIGN

Systematic literature review.

METHODS

Computerized journal databases were searched for relevant articles using terms: stroboscopy and treatment. Eligible articles were categorized and evaluated for the use of rater-related methodology, reporting of number of raters, types of raters, blinding, and rater reliability.

RESULTS

Of the 738 articles reviewed, 80 articles met inclusion criteria. More than one-third of the studies included in the review did not report the number of raters who participated in the study. Eleven studies reported results of rater reliability analysis with only two studies reporting good inter- and intrarater reliability.

CONCLUSION

The comparability and use of results from treatment studies that use LES are limited by a lack of rigor in rater methodology and variable, mostly poor, inter- and intrarater reliability. To improve our ability to evaluate and use the findings from voice treatment studies that use LES features as outcome measures, greater consistency of reporting rater methodology characteristics across studies and improved rater reliability is needed.

Correlation between Reflux and multichannel intraluminal impedance pH monitoring in untreated volunteers

OBJECTIVES/HYPOTHESIS

Although probable causative agents have been identified (e.g., refluxate components, tobacco smoke), the definitive mechanism for inflammation-related laryngeal mucosal damage remains elusive. Multichannel intraluminal impedance combined with pH monitoring (MII/pH) has emerged as a sensitive tool for diagnosis and characterization of gastroesophageal reflux disease with laryngopharyngeal manifestations. To determine the relationship between laryngeal signs and MII/pH, we examined correlations between Reflux Finding Score (RFS) ratings of videostroboscopic laryngeal examinations and findings from MII/pH.

STUDY DESIGN

Correlational study.

METHODS

Healthy, untreated volunteers (n = 142) underwent reflux diagnosis using data acquired from MII/pH testing. Eight trained clinicians performed RFS ratings of corresponding laryngeal examinations. Averaged RFS ratings were compared to MII/pH data using Pearson correlation coefficients. The relationship between RFS and MII/pH findings and demographic/clinical information (age, sex, smoking status, reflux) was assessed using general linear modeling. Rater reliability was evaluated.

RESULTS

Posterior commissure hypertrophy was negatively correlated with minutes of nonacid refluxate (R = -0.21, P = .0115). General linear modeling revealed that 28% to 40% of the variance in ratings of ventricular obliteration, erythema/hyperemia, vocal fold edema, diffuse laryngeal edema, posterior commissure hypertrophy, and granulation/granuloma could be explained by main and interaction effects of age, sex, smoking status, and reflux. Intra- and inter-rater reliability for RFS were poor-fair.

CONCLUSIONS

These results support the theory that the RFS is not specific for reflux in healthy, untreated volunteers, suggesting there may be alternate explanations for inflammatory clinical signs commonly ascribed to reflux in this population.

Frequency and factors associated with use of videolaryngostroboscopy in voice disorder assessment

OBJECTIVES/HYPOTHESIS

Videolaryngostroboscopy (VLS) is considered an important diagnostic tool in the evaluation of patients with laryngeal/voice disorders. We evaluated the frequency of, diagnoses associated with, and factors related to VLS use in the evaluation of outpatients with laryngeal/voice disorders.

STUDY DESIGN

Retrospective analysis of a large, national administrative U.S. claims database.

METHODS

Patients with a laryngeal disorder based on International Classification of Diseases, Ninth Revision, Clinical Modification (ICD-9-CM) codes from January 1, 2004, to December 31, 2008, seen by an otolaryngologist were included. Patient age, gender, geographic region, laryngeal diagnosis, comorbid conditions, and whether laryngoscopy or VLS was performed during the outpatient otolaryngology visit were collected.

RESULTS

A total of 168,444 unique patients saw an otolaryngologist for 272,112 outpatient visits. Of those, 6.2% of outpatient otolaryngology visits had a VLS performed. Patient age was related to VLS use, with lower odds in the elderly (≥ 65 years of age) and those 0 to 17 years of age. Geographic variation was noted, with higher odds of VLS use in urban versus rural areas and greater odds in the Northeast versus the South. Laryngeal diagnosis was associated with VLS use with greatest odds for patients with multiple diagnoses, vocal fold paralysis, and paresis-followed by nonspecific dysphonia and benign vocal fold/laryngeal pathology and followed by acute and chronic laryngitis and laryngeal cancer. Patients with gastro-esophageal reflux (GER) had greater odds of VLS use than patients without GER.

CONCLUSIONS

VLS was used in 6.2% of outpatient otolaryngology outpatient visits; and its use was influenced by multiple factors.

Reinnervation of bilateral posterior cricoarytenoid muscles using the left phrenic nerve in patients with bilateral vocal fold paralysis

Objective

To evaluate the feasibility, effectiveness, and safety of reinnervation of the bilateral posterior cricoarytenoid (PCA) muscles using the left phrenic nerve in patients with bilateral vocal fold paralysis.

Methods

Forty-four patients with bilateral vocal fold paralysis who underwent reinnervation of the bilateral PCA muscles using the left phrenic nerve were enrolled in this study. Videostroboscopy, perceptual evaluation, acoustic analysis, maximum phonation time, pulmonary function testing, and laryngeal electromyography were performed preoperatively and postoperatively. Patients were followed-up for at least 1 year after surgery.

Results

Videostroboscopy showed that within 1 year after reinnervation, abductive movement could be observed in the left vocal folds of 87% of patients and the right vocal folds of 72% of patients. Abductive excursion on the left side was significantly larger than that on the right side (P < 0.05); most of the vocal function parameters were improved postoperatively compared with the preoperative parameters, albeit without a significant difference (P > 0.05). No patients developed immediate dyspnea after surgery, and the pulmonary function parameters recovered to normal reference value levels within 1 year. Postoperative laryngeal electromyography confirmed successful reinnervation of the bilateral PCA muscles. Eighty-seven percent of patients in this series were decannulated and did not show obvious dyspnea after physical activity. Those who were decannulated after subsequent arytenoidectomy were not included in calculating the success rate of decannulation.

Conclusions

Reinnervation of the bilateral PCA muscles using the left phrenic nerve can restore inspiratory vocal fold abduction to a physiologically satisfactory extent while preserving phonatory function at the preoperative level without evident morbidity.