Glottic Function Research Articles

Gender Differences in Benign Vocal Fold Mass Treatment

Abstract: Benign vocal fold masses are seen commonly in amateur and professional voice users. Data shows that patients presenting with similar benign vocal fold masses are treated with different modalities at different rates based on their gender identity and patient preference. Professional and amateur voice users are also found to have different rates of treatment. Singing teachers have unique longitudinal relationships with their students. Knowledge of the effects of benign focal fold masses on the voice and glottic function along with treatment modalities can help singing teachers provide extra surveillance to students who may be at risk of suboptimal treatment. This article focuses on benign vocal fold mass classification, causes, symptoms, medical diagnosis, and treatment relevant to singing teachers with respect to the patient’s gender. Professional voice use is discussed as a potentially confounding factor to seeking treatment of benign vocal fold masses in the context of gender differences.

Videokymographic index of glottic function: an analysis of diagnostic accuracy.

To develop the Videokymographic Index of Glottic Function (VIGF), a composite indicator from digital videokymography parameters, captured by high-speed videolaryngoscopy exams of women with and without laryngeal alterations of behavioral etiology. The sample consisted of 92 women aged between 18 and 45 years. Fifty-five (55) women with behavioral dysphonia, presenting with laryngeal and voice alterations, and thirty-seven (37) women without any laryngeal and voice alterations. Voice evaluation was performed by consensus via an auditory-perceptual analysis of the sustained vowel /a/ at a habitual pitch and loudness. Voice classification was obtained by means of a general degree of dysphonia, where G0 indicated neutral voice quality and G1 to G3 indicated altered voice quality. Laryngeal images were captured via digital videokymography analysis of a sustained vowel /i/ at a habitual pitch and loudness. The VIGF was based on the midpoint of the glottal region for analysis. Logistic regression was performed using the MINITAB 19 program. Logistic regression was composed of two stages: Stage 1 consisted of the analysis of all variables, where the maximum opening and closed quotient variables showed statistical significance (p-value <0.05) and the model was well adjusted according to the Hosmer-Lemeshow test (p-value=0.794). Stage 2 consisted of the re-analysis of the selected variables, also showing a well-adjusted model (p-value=0.198). The VIGF was defined as follows: VIGF=e^(8.1318-0.2941AbMax-0.0703FechGlo)/1+e^(8.1318-0.2941AbMax-0.0703FechGlo). The VIGF demonstrated a cut-off value equal to 0.71. The probability of success was 81.5%, sensitivity 76.4%, and specificity 89.2%.

Índice videoquimográfico da função glótica: análise da precisão diagnóstica

ABSTRACT Purpose To develop the Videokymographic Index of Glottic Function (VIGF), a composite indicator from digital videokymography parameters, captured by high-speed videolaryngoscopy exams of women with and without laryngeal alterations of behavioral etiology. Methods The sample consisted of 92 women aged between 18 and 45 years. Fifty-five (55) women with behavioral dysphonia, presenting with laryngeal and voice alterations, and thirty-seven (37) women without any laryngeal and voice alterations. Voice evaluation was performed by consensus via an auditory-perceptual analysis of the sustained vowel /a/ at a habitual pitch and loudness. Voice classification was obtained by means of a general degree of dysphonia, where G0 indicated neutral voice quality and G1 to G3 indicated altered voice quality. Laryngeal images were captured via digital videokymography analysis of a sustained vowel /i/ at a habitual pitch and loudness. The VIGF was based on the midpoint of the glottal region for analysis. Logistic regression was performed using the MINITAB 19 program. Results Logistic regression was composed of two stages: Stage 1 consisted of the analysis of all variables, where the maximum opening and closed quotient variables showed statistical significance (p-value &lt;0.05) and the model was well adjusted according to the Hosmer-Lemeshow test (p-value=0.794). Stage 2 consisted of the re-analysis of the selected variables, also showing a well-adjusted model (p-value=0.198). The VIGF was defined as follows: VIGF=e^(8.1318-0.2941AbMax-0.0703FechGlo)/1+e^(8.1318-0.2941AbMax-0.0703FechGlo). Conclusion The VIGF demonstrated a cut-off value equal to 0.71. The probability of success was 81.5%, sensitivity 76.4%, and specificity 89.2%.

Effects of coronavirus disease-2019 on voice: our experience of laryngeal complications following mechanical ventilation in severe coronavirus disease-2019 pneumonitis and review of current literature.

Purpose of reviewDysphonia has been described as a major symptom of coronavirus disease-2019 (COVID-19). A literature review examining this topic was undertaken and is presented here, combined with insights from our experience in managing patients with laryngeal complications following mechanical ventilation for severe COVID-19 pneumonitis.Recent findingsNaunheim et al. reported that patients who are most at risk of needing intubation with COVID-19 disease are those with patient-specific risk factors and these are at an increased risk for subsequent laryngotracheal injury following intubation (1). In our cohort of 105 patients referred with laryngological symptoms postintubation for COVID-19 pneumonitis, 40% presented as urgent reviews, of which almost half had severe postintubation complications requiring surgery. Perceptual voice ratings and patient-reported voice ratings varied widely, but there was no significant change in voice scores postoperatively. The reflux symptom index (RSI) scores did improve significantly (p = 0.0266). The need for surgery was associated with the presence of comorbidities for instance hypertension, diabetes and obesity in our cohort. This is in support of reported association of comorbidity as a risk factor for intubation and subsequent development of postintubation airway complications.SummaryDysphonia following COVID-19 infection may have multiple causes. Literature reports demonstrate intubation injury, sensory neuropathy, and postviral neuropathy are associated with voice changes. Our personal experience has confirmed postintubation injury markedly affects glottic function with resultant dysphonia attributable to scar formation, posterior glottic stenosis, granulation and subglottic stenosis. Frequent surgical intervention is required for airway patency and may have short-term further deleterious effects on phonation, although in our cohort this is not statistically significant analysing Grade, Roughness, Breathiness, Asthenia, Strain, Voice Handicap Index-10 or Airway, Voice, Swallow scores. Maximal antireflux medications and advice statistically improved RSI scores postoperatively.

The Effects of Endotracheal Suctioning on Hemodynamic Parameters and Tissue Oxygenation in Pediatric Intensive Care Unit.

Airway secretions may increase in intubated patients due to the impaired mucociliary clearance, impaired cough reflex, abnormal glottic function, insufficient moisturizing, and respiratory tract infections. As with any intervention, patients should be cautiously monitored for possible complications during the endotracheal suctioning. Procedure-related changes in the cerebral and somatic tissue oxygenation, hemodynamics, and oxygen saturation can be observed in these patients. It is important to ensure maintenance of tissue oxygenation during these and other interventions performed in critically ill children. The aim of this study was to investigate the effects of the endotracheal suctioning on tissue oxygenation in patients undergoing mechanical ventilation in the pediatric intensive care unit. Cerebral and somatic near-infrared spectroscopy (NIRS) monitoring were performed noninvasively using standardized NIRS equipment as a means of monitoring regional tissue oxygenation. Vital signs, level of sedation, pain scores, and somatic and cerebral tissue oxygenation values of mechanically ventilated patients were recorded prospectively 5 minutes before, during, and after endotracheal suctioning. Cerebral NIRS measurements did not exhibit any statistically significant changes during endotracheal suctioning. Somatic NIRS levels changed significantly before, during, and after endotracheal suctioning and remained low throughout the procedure. Endotracheal suctioning is an invasive intervention that facilitates clearance of tracheal secretions and maintenance of the oxygenation and ventilation. The maintenance of the tissue oxygenation should be documented during these and other interventions performed on critically ill children. Somatic NIRS is a useful tool for monitoring tissue oxygenation during such procedures.

Effect of Unilateral Cordotomy on Perception of Dysphagia.

CO2 laser medial transverse cordotomy is a permanent static procedure performed to achieve adequate functional airway in cases of posterior glottic stenosis and bilateral vocal fold paralysis. Although it is the preferred method to manage long-term bilateral vocal fold immobility, it is widely believed that cordotomy has the potential to cause aspiration. The minimal existing data on the effect surgical enlargement of the glottic airway on swallowing function is heterogeneous. Through investigation of dysphagia after cordotomy, we hope to better understand the influence of glottic function and its role in dysphagia. The Eating Assessment Tool (EAT-10), is a validated dysphagia symptom-specific outcome measure. We hypothesized that EAT-10 scores would not change after CO2 laser cordotomy despite causing glottic insufficiency. Retrospective review was performed on sequential patients having undergone unilateral CO2 laser cordotomy with complete pre- and postoperative EAT-10 questionnaire data available for evaluation. Fifteen patients were available for analysis; 10 patients underwent primary unilateral medial transverse cordotomy, 5 patients underwent revision cordotomy, and 20 unique procedures were included in the dataset. The median EAT-10 score during the visit prior to surgery was 3.5, whereas the post-surgery median score was 2. Furthermore, the median difference of 0 was statistically non-significant (P = .91). CO2 laser cordotomy does not contribute to patient-reported dysphagia despite creating glottic incompetence. This suggests vocal fold apposition may play a less significant role in normal swallowing function than widely believed.

Is There a Relationship Between Vocal Effort and VHI?

Vocal effort is often a symptom reported when a patient experiences a voice disorder. The aim of this investigation was to compare Voice Handicap Index (VHI) scores among patients with primary complaints of vocal effort (VE) versus vocal quality (VQ) and both vocal effort and quality (VQ+VE). A secondary aim was to compare Glottal Function Index (GFI), and glottic closure pattern between patients with the aforementioned primary presenting complaints and laryngeal pathology diagnosis. Prospective outcomes database design METHODS: Patients were identified with presenting complaints of VQ, VE, or VQ+VE who completed the VHI. Seven hundred and thirteen subjects who met criteria were categorized across three complaint groups and five laryngeal pathologies. Variables selected included age, gender, diagnosis, VHI, GFI, and 12-Item Short Form Health Survey. VHI and GFI scores were compared between the three presenting complaints. Relationships between the categorical variables and glottic closure were also assessed. Significant differences in total VHI were measured among all three presenting-complaint categories (P < 0.0001). Patients with VE only complaints had significantly greater VHI scores than those patients who report VQ only complaints. VHI scores were significantly higher for patients with combined complaints of VQ+VE as compared to VQ only or VE only. Significant differences in GFI were measured across all three complaints, and GFI was significantly higher in VE only as compared to VQ only (P < 0.001). Glottic closure pattern was not statistically significant in the variables examined. VHI scores were significantly different within pathology subgroups (P < 0.03). VE only complaints affect quality of life with and without concomitant VQ complaints. Patients with VE complaints perceive a higher level of glottic dysfunction. An underlying mechanism for increased VE could be altered glottic function, however, we were unable to suggest a correlation between glottic closure and GFI.

Development of a Closed-Loop Stimulator for Laryngeal Reanimation: Part 2. Device Testing in the Canine Model of Laryngeal Paralysis.

Laryngeal paralysis of central or peripheral origin can potentially be treated using functional electrical stimulation (FES) of laryngeal muscles. Experiments in canines (dogs) were performed using implant prototypes capable of closed-loop FES to refine engineering designs and specifications, test surgical approaches for implantation, and better understand the in vivo effects of laryngeal muscle stimulation on short- and long-term glottic function. Prospective, laboratory. We designed and tested a series of microprocessor-based implantable devices that can stimulate glottic opening or closing based on input from physiological control signals (real-time processing of electromyographic [EMG] signals). After acute device testing experiments, 2 dogs were implanted for 8 and 24 months, with periodic testing of closed-loop laryngeal muscle stimulation triggered from EMG signals. In total, 5 dogs were tested for the effects of laryngeal muscle stimulation on vocal fold (VF) posturing in larynges with nerve supplies that were intact (7 VFs), synkinetically reinnervated (2 VFs), or chronically denervated (1 VF). In 3 cases, the stimulation was combined with airflow-driven phonation to study the consequent modulation of phonatory parameters. Initial device prototypes used inductive coupling for power and communication, while later iterations used battery power and infrared light communication (detailed descriptions are provided in the Part 1 companion paper). Two animals were successfully implanted with the inductively powered units, which operated until removed at 8 months in 1 animal or for more than 16 months in the second animal. Surgically, the encapsulated implants were well tolerated, and procedures for placing, attaching, and connecting the devices were developed. To simulate EMG control signals in anesthetized animals, we created 2 types of nerve/muscle signal sources. In one approach, a neck muscle had a cuff electrode placed on its motor nerve that was connected to transdermal electrical connection ports for periodic testing. In the second approach, the recurrent laryngeal nerve on one side of the larynx was stimulated to generate a VF EMG signal, which was then used to trigger FES of the paralyzed contralateral side (eg, restoring VF movement symmetry). Implant testing identified effective stimulation parameters and closed-loop stimulation artifact rejection techniques for FES of both healthy and paralyzed VFs. Stimulation levels effective for VF adduction did not cause signs of discomfort during awake testing. Our inductive and battery-powered prototypes performed effectively during in vivo testing, and the 2 units that were implanted for long-term evaluation held up well. As a proof of concept, we demonstrated that elicited neck strap muscle or laryngeal EMG potentials could be used as a control signal for closed-loop stimulation of laryngeal adduction and vocal pitch modulation, depending on electrode positioning, and that VFs were stimulable in the presence of synkinetic reinnervation or chronic denervation.

International neuromonitoring study group guidelines 2018: Part II: Optimal recurrent laryngeal nerve management for invasive thyroid cancer-incorporation of surgical, laryngeal, and neural electrophysiologic data.

The purpose of this publication was to inform surgeons as to the modern state-of-the-art evidence-based guidelines for management of the recurrent laryngeal nerve invaded by malignancy through blending the domains of 1) surgical intraoperative information, 2) preoperative glottic function, and 3) intraoperative real-time electrophysiologic information. These guidelines generated by the International Neural Monitoring Study Group (INMSG) are envisioned to assist the clinical decision-making process involved in recurrent laryngeal nerve management during thyroid surgery by incorporating the important information domains of not only gross surgical findings but also intraoperative recurrent laryngeal nerve functional status and preoperative laryngoscopy findings. These guidelines are presented mainly through algorithmic workflow diagrams for convenience and the ease of application. These guidelines are published in conjunction with the INMSG Guidelines Part I: Staging Bilateral Thyroid Surgery With Monitoring Loss of Signal. Level of Evidence: 5 Laryngoscope, 128:S18-S27, 2018.

Evaluating Post-Radiotherapy Laryngeal Function with Laryngeal Videostroboscopy in Early Stage Glottic Cancer.

Dysphonia is common among patients with early stage glottic cancer. Laryngeal videostroboscopy (LVS) has not been routinely used to assess post-radiotherapy (RT) voice changes. We hypothesized that LVS would demonstrate improvement in laryngeal function after definitive RT for early-stage glottic cancer. Blinded retrospective review of perceptual voice and stroboscopic parameters for patients with early glottic cancer and controls. High-volume, single-institution academic medical center. Fifteen patients underwent RT for Tis-T2N0M0 glottic cancer and were evaluated with serial LVS exams pre- and post-RT. Stroboscopic assessment included six parameters: vocal fold (VF) vibration, VF mobility, erythema/edema, supraglottic compression, glottic closure, and secretions. Grade, roughness, breathiness, asthenia, strain (GRBAS) voice perceptual scale was graded in tandem with LVS score. Assessments were grouped by time interval from RT: pre-RT, 0-4, 4-12, and >12 months post-RT. 60 LVS exams and corresponding GRBAS assessments were reviewed. There were significant improvements in ipsilateral VF motion (P = 0.03) and vibration (P = 0.001) and significant worsening in contralateral VF motion (P < 0.001) and vibration (P = 0.008) at >12 months post-RT. Glottic closure significantly worsened, most prominent >12 months post-RT (P = 0.01). Composite GRBAS scores were significantly improved across all post-RT intervals. LVS proved to be a robust tool for assessing pre- and post-RT laryngeal function. We observed post-RT improvement in ipsilateral VF function, a decline in contralateral VF function, and decreased glottic closure. These results demonstrate that LVS can detect meaningful changes in VF and glottic function and support its use for post-RT evaluation of glottic cancer patients.

Management of laryngoceles by transoral robotic surgery.

We herein report our experience with the management of laryngoceles using transoral robotic surgery (TORS). A bicentric retrospective study was conducted from November 2009 to September 2015. The inclusion criteria were treatment of a laryngocele by TORS and no malignancy on definitive histopathology. Surgery was performed using the Da Vinci (Intuitive®) surgical robot. Surgical methods and post-operative outcomes were evaluated. Eight patients (four men and four women) presenting with a laryngocele (one bilateral case) were included (mean age 61.8years). There was one covering tracheotomy. The average post-operative stay was 3.75days. Three patients treated for a combined laryngocele had a nasogastric feeding tube inserted for 5days. One patient experienced late laryngeal bleeding that required surgical treatment. TORS may offer an efficient treatment option for laryngoceles. The use of precise and flexible instruments and a three-dimensional camera allow fine dissection of these tumours, preserving the glottic space and vocal function, even for combined laryngoceles extending deep within the neck.Evidence level: 4.

Clinical Implications of Assisted Peak Cough Flow Measured With an External Glottic Control Device for Tracheostomy Decannulation in Patients With Neuromuscular Diseases and Cervical Spinal Cord Injuries: A Pilot Study

ObjectiveTo investigate the clinical usefulness and significance of an external control device substituting for glottic function in determining the feasibility of decannulation in tracheostomized patients with neuromuscular diseases and cervical spinal cord injuries whose assisted peak cough flow (APCF) was unmeasurable or <160L/min. DesignBefore-after trial. SettingInpatient setting in a university hospital. ParticipantsTracheostomized patients (N=16; 11 with neuromuscular diseases and 5 with cervical spinal cord injuries) were recruited. InterventionsUnassisted peak cough flow (UPCF) and APCF were measured with and without an external glottic control device. Among patients whose APCF without the device was <160L/min, if their APCF with the device was measured as ≥160L/min, they were decannulated. After decannulation, UPCF and APCF were measured again. Main Outcome MeasuresAPCF with and without an external glottic control device as well as APCF after decannulation. ResultsAfter successful decannulation, APCFs were greater than or equal to those measured with the device before decannulation. No patients underwent intubation or retracheostomy, and there were no respiratory complications. ConclusionsThe external glottic control device substituting for innate glottic function is beneficial for determining tracheostomy decannulation. It provides an objective and accurate APCF. It is particularly helpful for patients whose APCF is ≥160L/min while using the device, even if APCF is <160L/min without this device.

Prospective study of vocal fold function after loss of the neuromonitoring signal in thyroid surgery: The International Neural Monitoring Study Group's POLT study.

Intraoperative neuromonitoring identifies recurrent laryngeal nerve (RLN) injury and gives prognostic information regarding postoperative glottic function. Loss of the neuromonitoring signal (LOS) signifies segmental type 1 or global type 2 RLN injury. This study aimed at identifying risk factors for RLN injury and determining vocal fold (VF) function initially and 6 months after definitive LOS. Prospective study encompassing 21 hospitals from 13 countries. Included in this study were patients with persistent intraoperative LOS. At first postoperative laryngoscopy, early VF palsy was present in 94 of all 115 patients with LOS (81.7%): in 53 of 56 patients (94.6%) with type 1 injury and 41 of 59 patients (69.5%) with type 2 injury. In LOS type 1, women outnumbered men >5-fold. Traction produced LOS type 1 in 38 of 56 patients (67.9%) and LOS type 2 in 54 of 59 patients (91.5%). Course of the RLN posterior and/or anterior to the inferior thyroid artery, extralaryngeal branching, or tuberculum of Zuckerkandl did not increase VF palsy rates. Permanent VF palsy rates were also lower (P = .661) after LOS type 2 than after LOS type 1: 6.8% (four of 59 patients) versus 10.7% (six of 56 patients). Intraoperative administration of steroids did not diminish postoperative VF palsy rates. LOS type 1 entails more severe nerve damage than LOS type 2, affecting women disproportionately. Both LOS types, being primarily associated with traction injury, are unaffected by variant neck anatomy in expert hands and unresponsive to steroids. 2b Laryngoscope, 126:1260-1266, 2016.

Voice Outcome Following Carbon Dioxide Laser Assisted Microlaryngeal Surgery.

Very few studies have been conducted in South Indian population to evaluate glottic function and voice outcome following carbon dioxide (CO2) laser assisted microsurgery for benign lesions of the larynx. This is a descriptive study which aims at assessing the voice outcome (perceptual and acoustic) and vocal fold function (stroboscopic) following CO2 laser excision in benign vocal fold lesions. 50 adult patients with benign laryngeal lesions were selected to undergo CO2 laser excision in super-pulse mode at power setting of 6 watts. Perceptual analysis was done using GRBAS score. Voice analysis was done using Praat software and fundamental frequency, jitter, shimmer and harmonics to noise ratio were assessed. Stroboscopy was done to evaluate vocal fold function using glottic closure and mucosal wave pattern as parameters. Evaluation of these parameters was done pre-operatively and at 2, 6weeks and 3months post-operatively. Perceptual analysis revealed a significant improvement in the GRBAS score after surgery (p<0.001). Acoustic analysis showed that all the parameters improved significantly after surgery (p<0.001). Stroboscopy showed that vocal fold function improved in 98% of patients in terms of completeness of glottic closure and regular, periodic mucosal wave. Super-pulse micro-spot carbon dioxide laser is a safe and effective treatment option for benign lesions of vocal folds, with excellent voice outcome.

Aerodynamic Measures and Biofeedback as Management in Persistent Paradoxical Vocal Fold Motion and Reverse Phonation

Paradoxical vocal fold motion (PVFM) and reverse phonation are characterized by aberrant vocal fold adduction. To date, there have been no studies examining the aerodynamic events during reverse phonation. We present an unusual case of persistent reverse phonation secondary to respiratory distress associated with PVFM. Case report. We present the case of a 42-year-old female with sudden onset of respiratory distress associated with PVFM and persistent reverse phonation. She underwent baseline aerodynamic measurements followed by trial therapy. Through the use of instrumental and tactile aerodynamic biofeedback, the patient was able to coordinate exhalatory breath pressure flow during phonation, which resulted in immediately improved voice quality from highly dysphonic to nearly normal voice quality. Patients with reverse phonation seldom undergo aerodynamic testing as part of the initial diagnostic and management program. Our case study demonstrates the effectiveness of aerodynamic technology to enable a patient with aberrant glottic function to recognize inspiratory phonation events and to reestablish consistent expiratory flow/pressure egress in speech tasks. Instrumental and tactile biofeedback is effective for reinforcement of normal flow patterns during speech tasks.

Intraoperative monitoring: Normative range associated with normal postoperative glottic function

Despite increasing use of intraoperative nerve monitoring (IONM), there is limited information on normative electrophysiologic electromyographic (EMG) parameters. The objective of this study was to define normative parameters of recurrent laryngeal nerve (RLN) intraoperative neuromonitoring during thyroid surgery associated with normal postoperative vocal cord function. Prospective data collection in a tertiary care center. Quantitative analysis of evoked waveform amplitude and threshold was performed on 125 patients with 167 nerves at risk. Values were displayed as a mean with 5th percentile and 95th percentiles (5th-95th). Postoperative vocal cord function in all patients was documented. All patients had normal postoperative laryngeal function (group I-normal) except for two patients who had postoperative transient vocal cord paralysis (group II-abnormal/outlier). The final amplitude between 247 and 3607 μV at the end of dissection/end of surgery was associated in all group I patients with a normal postoperative neural function. Final intraoperative amplitude measures for group II averaged just 97.5 μV, significantly different than our normative ranges obtained for group I, and fell outside of the group I 5% to 95% percentile range (P = .016). Final amplitude adequately predicted postoperative RLN impaired function immediately after surgery. We propose IONM EMG data criteria that predict normal postoperative vocal cord function monitoring and provide information about nerve functioning at the end of the operation, thereby allowing adaptation of the surgical strategy when a bilateral procedure is indicated to avoid bilateral nerve paralysis.

Development and Validation of a New Outcome Score in Subglottic Stenosis

We prospectively evaluated a clinical and endoscopic score, the tracheal endoscopic clinical score (TECS), developed as a disease-specified outcome measure in adult patients undergoing operation for subglottic stenosis. We also performed a retrospective chart review to identify preoperative and intraoperative risk factors for worse TECS. The TECS includes endoscopic (vocal cord and glottic function, anastomotic healing, and patency) and interview (respiration, voice, swallow) variables, and was administered at 6-month follow-up. Endoscopic and subjective domains were weighted to obtain a continuous TECS index ranging from 0 (best) to 1 (worse). The TECS and preoperative variables relationships were evaluated by univariate and multivariate analysis. We collected data (January 2009 to December 2010) from 30 patients (mean age, 48.3±19 years) undergoing subglottic resection and primary reconstruction. Stenosis etiology was postintubation (n=8), idiopathic (n=2), tracheostomy (n=18), and malignant (n=2). Surgery included Pearson operation with (n=7) or without (n=23) a Liberman-Mathisen cricoplasty. Mean length of resected trachea was 30.5±13.5 mm, and mean hospital stay was 7.4 days. Mortality rate was 1 patient (3.3%). The univariate analysis showed positive correlation between 6-month TECS and degree of stenosis (McCaffrey and Cotton scale 0 to 4) stage 4, tracheostomy or T-tube at surgery, bottleneck-type transition stenosis, and resection length. At multivariate analysis, the presence of tracheostomy, bottleneck-type transition stenosis and resection length were indicators of worse postoperative functional result. The TECS seems to be a valid and simple instrument to identify preoperative variables predicting worse results and to assess postoperative outcome. Validation on larger series is necessary.

Local vascularized flaps for augmentation of reinke's space

The purpose of this study is to describe and test a novel surgical strategy for augmentation of Reinke's space using vascularized flaps: a thyroid ala perichondrium flap (TAP) and a composite thyroid ala perichondrium flap (CTAP) from the anterior larynx. We hypothesized that these specially designed vascularized flaps would remain viable once inset into the lamina propria, and that they would not disrupt rheologic, biomechanical, and histologic properties of the native vocal fold. Experimental. In vivo canine model. The length and volume of test flaps harvested in six adult human cadaveric larynges were analyzed to determine suitability for use in augmentation in the lamina propria. Also, 12 beagles randomly underwent unilateral placement of either TAP or CTAP, which were designed in accordance with the human adult cadaveric experiments. Flap perfusion was measured before and after harvest with laser Doppler. After 1 month, the beagles were humanely sacrificed and their larynges subjected to aerodynamic and acoustic evaluation using an excised larynx apparatus. The vocal fold lamina propria of four larynges--two TAP and two CTAP--underwent rheologic evaluation using a simple-shear rheometer. The remaining eight larynges underwent quantitative histologic and immunohistochemical evaluation. The survival and complication (swallowing, airway, local wound) rates of all dogs were noted. Initial studies with adult human cadaveric larynges established that TAP and CTAP possessed length and volume greater than native lamina propria. In the canine experiments, the perfusion change in the flaps was similar between flap groups. The damping ratio (ζ), dynamic viscosity (η'), elastic shear modulus (G'), and viscous shear modulus (G″) of treated and untreated native vocal folds were not statistically different. The glottic function measures of vocal efficiency, laryngeal resistance, jitter, shimmer, and harmonics-to-noise ratio (HNR) of treated and normal larynges were not statistically different. Similarly, the values for collagen, elastin, and glycosaminoglycans (GAGs) in treated and untreated vocal folds were not statistically different. Also, neither neochrondrogenesis nor neoosteogenesis was detected in any treated vocal fold. The values for vascular and cellular proliferation in treated and untreated vocal folds were not statistically different. All test dogs survived and had no complications related to swallowing, airway distress, or the local wound. The test flaps described and tested in this study appear to have conceptually attractive features for augmentation of Reinke's space. When placed in an in vivo setting TAP and CTAP did not reveal unfavorable vascular, rheologic, aerodynamic, acoustic, or histologic characteristics. There was no unanticipated morbidity or mortality to the test animals. Long-term viability of these flaps is unknown. TAP and CTAP may open novel pathways for correction of glottic defects and may offer crossover opportunities with tissue engineering techniques.

Prolonging Survival in Amyotrophic Lateral Sclerosis

To assess the efficacy of noninvasive ventilatory support and intermittent positive pressure ventilation via uncuffed tracheostomy tubes (uTIPPV) to prolong survival in amyotrophic lateral sclerosis. Survival was prolonged by continuous noninvasive ventilatory support or TIPPV dependence. Once noninvasive ventilatory support was no longer adequate for six noninvasive ventilatory support users, they and 22 others underwent tracheotomy within 1 mo of measurement of spirometry (forced vital capacity and forced volume expired in 1 sec), peak cough flows, maximum insufflation capacity, manually assisted peak cough flows, and mechanically assisted peak cough flows. Glottic function was estimated by maximum insufflation capacity, FVC difference, and bulbar-innervated muscle function by Norris scale bulbar-innervated muscle subscore. Cuffless tubes were replaced by cuffed ones when hypoventilation developed despite increasing uTIPPV volumes. The survival of 22 patients was prolonged by continuous noninvasive ventilatory support dependence for 7.8 +/- 8.1 mos (range, 1-36 mos; median, 5 mos) after 13.9 +/- 11.2 mos (range, 2-36 mos) of part-time noninvasive ventilatory support. Six of these and 22 others underwent tracheotomy and initially used uTIPPV effectively. For ten of the 28 (35.7%) patients, the tubes had to be replaced by cuffed ones after 5.7 +/- 7.8 mos with the other 18 still using tracheostomy intermittent positive pressure ventilation volumes via uncuffed tubes for 20.2 +/- 17.6 mos at data collection. Pretracheotomy FVC was significantly lower in the ten patients who eventually required cuffed tubes (0.70 +/- 0.44 vs. 1.06 +/- 0.43 L, P < 0.05). The bulbar-innervated muscle was significantly lower when the uTIPPV users required cuffed TIPPV than when beginning uTIPPV (Norris scale bulbar-innervated muscle subscore, 3.20 +/- 1.30 vs. 8.00 +/- 3.20, P < 0.05), respectively. Noninvasive and tracheostomy IPPV via cuffless tubes can prolong survival for patients with amyotrophic lateral sclerosis until excessive air leak and hypoventilation necessitate a cuffed tube.

Carbon dioxide laser-assisted phonosurgery for benign glottic lesions

The objectives of the study were (1) to evaluate glottic function following carbon dioxide laser-assisted phonosurgery of benign laryngeal disease, and (2) to assess postoperative glottic morphology and disease recurrence rates, using the study design of comparative prospective non-randomized case series of patients with benign glottic pathology treated by laser-assisted phonosurgery over 10 years. 235 consecutive patients had pre- and postoperative data collected by objective laryngeal examination, videostroboscopy recording of vocal fold mucosal wave movement, electroacoustic voice analysis (statistical analysis: Wilcoxon test) and perceptual voice evaluation. Comparing pre- and postoperative functional results demonstrated a statistically significant improvement in all spectrographically analysed objective voice parameters (P < 0.001). Postoperative morphological analysis confirmed three recurrences of granuloma and one of Reinke's oedema. Carbon dioxide laser-assisted voice restoration for benign glottic disease is effective.