Mean Airflow Rate Research Articles

Influence of Superior Laryngeal Nerve Injury on Glottal Configuration/Function of Thyroidectomy‐Induced Unilateral Vocal Fold Paralysis

Recurrent laryngeal nerve (RLN) injury may induce unilateral vocal fold paralysis (UVFP). During thyroidectomy, the most common cause of UVFP, the superior laryngeal nerve (SLN), is also at risk of injury. In the literature, the influence of SLN injury on glottal configuration and function in patients with UVFP remains controversial. The present study investigates SLN injury influence on glottal configuration and function in patients with UVFP after thyroidectomy. Prospective controlled study. Tertiary medical center. The SLN and RLN function of 34 patients with UVFP after thyroidectomy was determined by laryngeal electromyography. The subjects were dichotomized into the isolated RLN injury group (n = 26) or the concurrent SLN/RLN injury group (n = 8). We evaluated glottal angle and paralyzed vocal fold shape during inspiration, normalized glottal gap area, and glottal shape during phonation. The glottal function measurements included voice acoustic and aerodynamic analyses and the Voice Handicap Index. The aforementioned parameters of the RLN and concurrent SLN/RLN injury groups were compared. There were no statistical differences in glottal configuration such as glottal angle, paralyzed vocal fold shape, normalized glottal gap area, and glottal shape between the RLN and concurrent SLN/RLN injury groups. There were also no significant differences in other glottal function analyses including fundamental frequency, mean airflow rate, phonation quotient, maximal phonation time, and Voice Handicap Index. In the present study, we did not find any evidence that SLN injury could significantly influence the glottal configuration and function in patients with UVFP.

Short-Term Treatment Results for Unilateral Vocal Fold Palsy Induced by Mediastinal Lesions

Vocal fold paralysis (VFP) is a frequent complication of surgery of mediastinal structures. This study evaluated the characteristics and short-term treatment outcomes of injection laryngoplasty for unilateral VFP (UVFP) induced by mediastinal lesions. The enrolled patients (n=60) underwent injection laryngoplasty once because of UVFP and were divided into two groups according to cause (group A, thyroidectomy and group B, mediastinal surgery). Voice analysis was performed preoperatively and at 1 month postoperatively. The glottal gap; the Grade, Roughness, Breathiness, Asthenia, and Strain scale; acoustic analysis; and aerodynamic results were measured. Group A and group B comprised eight and 52 patients, respectively. Group B patients were older than group A patients (P<0.05). The injected volume in group B (0.91±0.23mL) was larger than that of group A (0.38±0.17mL; P=0.022). Group B (13.35±4.69 units) showed a larger glottal gap than group A (6.64±4.05 units; P=0.017), and the glottal gap decreased after the procedure. In both groups, most preoperative acoustic parameters except roughness improved after injection laryngoplasty. The preoperative maximum phonation time of group B (2.87±1.11seconds) was shorter than that of group A (7.04±2.58seconds), and it improved after injection. Mean airflow rate improved significantly after injection in both groups. Mediastinal lesion-induced UVFP is associated with a larger glottal gap than that caused by an injury induced by thyroidectomy. Despite large glottal gap, injection laryngoplasty improves voice outcomes in such types of UVFP.

Over-adduction of the unaffected vocal fold during phonation in the unilaterally paralyzed larynx

Conclusions: Over-adduction of the unaffected vocal fold may not compensate vocal function in unilateral vocal fold paralysis (UVFP). Objective: To determine whether over-adduction of the unaffected vocal fold has any impact on vocal function in patients with UVFP. Methods: A total of 101 patients with UVFP who underwent three-dimensional computed tomographic (CT) examination of the larynx served as subjects. Three-dimensional endoscopic images together with coronal images during phonation were produced to evaluate over-adduction of the unaffected fold, posterior glottal gap, and differences in the vertical position and thickness between the vocal folds. Maximum phonation time (MPT) and mean airflow rate (MFR) were measured. Results: In all, 47 patients showed over-adduction. Their MPT and MFR were 4.9 ± 2.9 s and 653 ± 504 ml/s, respectively. The remaining 54 did not show over-adduction. Their MPT and MFR were 4.7 ± 2.7 s and 574 ± 384 ml/s, respectively. There were no significant differences in MPT or MFR between the two groups. Of the 47 patients with over-adduction, 9 showed no posterior glottal gap. However, their vocal function was not significantly different from that of 38 patients with posterior glottal gap or from that of 43 patients without over-adduction and having a posterior glottal gap.

Multidimensional evaluation of vocal quality in children with cochlear implants: a cross‐sectional, case‐controlled study

This study aimed to compare the differences in vocal quality between Mandarin-speaking children with cochlear implants and normal-hearing peers and to understand which cochlear implant usage parameters may predict unfavourable voice outcomes. A cross-sectional, case-controlled study. A tertiary medical centre. Thirty-five pre-lingually deaf children (age = 10.3 ± 1.6 years; 17 boys and 18 girls) who had used cochlear implants for >2 years and 35 age- and gender-matched controls with normal hearing. Through sustained phonation of /a/ and reading of the Hare and Tortoise passage, the subjects' voice quality was analysed with aerodynamics and acoustics. A six-point scale was used for auditory-perceptual evaluation. A Pediatric Voice-Related Quality of Life Survey was filled out by the caregivers. The implanted subjects had significantly lower mean airflow rate (P = 0.006), higher phonation threshold pressure (P < 0.001), higher fundamental frequency variations (P < 0.001) and peak-amplitude variations (P < 0.001), wider fundamental frequency range (P = 0.043), wider speaking intensity range (P = 0.015) and greater perceptual severity level of monotone (P < 0.001), resonance (P < 0.001), loudness (P < 0.001) and strain (P = 0.006) than their normal-hearing peers. Duration of postoperative rehabilitation was an independent predictor of unfavourable mean speaking fundamental frequency (odds ratio = 8.56, P = 0.008). Inadequate postoperative rehabilitation may hinder the normalisation of Mandarin-speaking implantees' voice quality. A multidimensional analysis may precisely evaluate the voice of paediatric implantees; however, the generalisability of these findings requires different forms of validation, including data from other languages and other institutions.

The Effects of Botulinium Toxin in Vocal Nodules

Background and ObjectivesZZVocal nodules are the most common voice disorder due to vocal misuses. Vocal nodules are primarily treated with voice therapy and are rarely removed through laryngomicrosurgery. Although the rate of recovery for individual patients may vary, 60-70% of them are fully treated. Because vocal nodules have many possible causes, 30-40% of patients remain untreated. Also, vocal nodules recurrence after the surgical treatment is sometimes observed. The author claims that incomplete contact between vocal cords during phonation is a major cause of the vocal nodules. Most vocal nodules do occur from incomplete contact between vocal cords during phonation, and various voice therapies are designed to improve habitual misuses of the vocal cords. However, vocal nodules tend to remain unhealed unless patients change their habitual misuses of the vocal cords. The cricothyroid muscle tension is known to hinder the contact between vocal cords. The author injected a restricted amount of botulinium toxin to the cricothyroid muscle to reduce the muscle tension and observed changes in vocal cords’ movement. Subjects and MethodZZIn this study, the author injected botulinium toxin to the cricothyroid muscle of 21 patients. For 2-4 weeks, we observed patients’ responses to the treatment, by measuring changes in subglottal pressure, mean air flow rate, maximum phonation time, jitter, shimmer, noise-to-harmonic ration of patients and subjective evaluation of voice changes. In addition, the author conducted stroboscopy to evaluate the usefulness of the treatment. ResultsZZThe improvement was in the subjective evaluation of voice changes and stroboscopic findings. ConclusionZZThe observation demonstrated a great improvement in vocal nodules after the injection of botulinium toxin into the cricothyroid muscle.

Phonological outcome of laryngeal framework surgery by different anesthesia protocols: a single-surgeon experience

Conclusion: Similar to combined arytenoid adduction and medialization laryngoplasty (i.e. combined surgery) under local anesthesia, general anesthesia by intubation or by the laryngeal mask airway (LMA) method significantly improves phonological outcome. Thus, laryngeal framework surgery under general anesthesia is a promising surgical approach for selected patients with unilateral vocal cord paralysis (UVCP). Objective: The advantages of laryngeal framework surgery under local anesthesia have been described, but no studies exist concerning the difference in phonological outcome of laryngeal framework surgery performed under general anesthesia. To add new information, we retrospectively investigated the phonological outcome of the combined surgery performed under three different anesthesia protocols. Methods: Thirty-nine consecutive patients with severe UVCP underwent the combined surgery under three anesthesia protocols performed by a single surgeon: (1) under general anesthesia by intubation, (2) under general anesthesia using LMA, and (3) under local anesthesia. Results: Under all anesthesia protocols, the vocal cords of most patients could be positioned such that the best vocal outcome could be expected. Statistical analyses demonstrated improved maximum phonation time and mean airflow rate, and grade, roughness, breathiness, asthenia, and strain (GRBAS) scale in all patients, regardless of their anesthesia protocol. Furthermore, of the three protocols, local anesthesia had the shortest operation time.

Laryngeal Muscle Activity in Unilateral Vocal Fold Paralysis Patients Using Electromyography and Coronal Reconstructed Images

Objectives: Assess laryngeal muscle activity in patients with unilateral vocal fold paralysis (UVFP) using laryngeal electromyography (LEMG) and coronal multi-planar reconstructed images (coronal images). Methods: Twenty-one patients suffering from paralytic dysphonia, who had had onset of UVFP more than 6 months previously, underwent LEMG, phonatory function, and coronal images. For LEMG analysis, a four-point scale was employed to grade motor unit (MU) recruitment; 4+: absent, 3+: greatly decreased, 2+: moderately decreased, and 1+: mildly decreased (less than full interference). Maximum phonation time (MPT) and mean airflow rate (MFR) were employed. Coronal images during phonation and inhalation were assessed focusing on differences in thickness and vertical position between the vocal folds during phonation. Results: MU recruitment results were three patients for 1+, five for 2+, six for 3+, and seven for 4+. MPT was positively correlated with the MU recruitments ( P = 0.011). The thinning of the affected fold was evident during phonation in 20 of the 21 subjects. All 8 subjects with MU recruitments 1+ and 2+ showed the affected fold located at an equal level to the healthy fold. Twelve of 13 subjects with MU recruitments 3+ and 4+ showed the affected fold located at a higher level than the healthy fold. There was a significant difference between MU recruitment and vertical position of the affected fold ( P = 0.001). Conclusions: MU recruitments in patients with UVFP may be related to phonatory function and the vertical position of the affected fold. Synkinetic reinnervation may occur in some cases with UVFP.

Implantation of Contralaterally Harvested Nerve‐Muscle Pedicle Flap Combined with Arytenoid Adduction for Paralytic Dysphonia

Objectives: 1) Describe operative procedures to reinnervate the thyroarytenoid muscle (TA) on the paralyzed side using a modified nerve-muscle pedicle (NMP) flap implantation harvested on the contralateral side combined with arytenoid adduction (AA). 2) Assess time-dependent improvement in vocal function during postoperative follow-up. Methods: Prospective case series. Four patients underwent modified NMP flap implantation combined with AA for paralytic dysphonia between August 2009 and January 2013. The NMP flap was harvested on the contralateral side because of scar formation on the paralyzed side and was secured to the TA under microscopic control. Three of them were followed over one year, and their voice outcomes, determined by 5 objective and 2 subjective parameters, were evaluated preoperatively and at 4 different time points after surgery. Results: On average, maximum phonation time and mean airflow rate improved from 5.4s and 569mL/s preoperatively to 24.2s and 116mL/s 12 months postoperatively, respectively. Jitter, shimmer, and harmonics-to-noise ratio also improved from 10.5%, 16.4%, and 4.2dB preoperatively to 1.7%, 11.2%, and 6.8dB postoperatively, respectively. Grade overall and breathiness of GRBAS scale became much better from 2.6 and 2.4 preoperatively to 0.2 and 0.0 12 months postoperatively, respectively. Stroboscopic images together with voice during follow-up period will be presented. Conclusions: Combination of AA and a modified NMP flap implantation harvested on the contralateral side improves long-term voice outcomes of paralytic dysphonia. Therefore, patients in whom the ansa cervicalis nerve is unavailable due to high level scar formation could have a great benefit by these operative methods.

Voice Quality After Surgical Treatment for Thyroid Cancer

Thyroidectomy is a standard treatment for thyroid cancers. Hoarseness due to the paralysis of the recurrent laryngeal nerve is one of the most common postoperative complications, and has been studied by many investigators. However, voice quality after thyroidectomy in patients in whom recurrent laryngeal nerves were preserved and vocal cord morbidity was endoscopically normal has not been well studied. To understand voice quality after thyroidectomy further, we conducted a time-course analysis of voice quality in patients who had thyroidectomy with normal cord morbidity by various measures. We evaluated voice parameters including the Voice Handicap Index-10 (VHI-10), the vocal efficacy index, the fundamental frequency (F0), the maximum phonation time (MPT), the mean air flow rate (MFR), jitter, shimmer, and the noise-to-harmonics ratio (NHR) before and after total thyroidectomy (TT) or lobectomy (LO) for thyroid cancers in 110 patients in whom the recurrent laryngeal nerves were preserved without apparent injury and normal vocal cord mobility was confirmed by endoscopic examination. Thirteen patients who underwent parotidectomy were enrolled as controls. Immediately after surgery, significant decreases in MPT (p=0.003) and significant increases in jitters, shimmers, and NHR (p=0.0002, 0.02, and 0.03, respectively) were observed in the patients who underwent TT. In comparison with the controls, jitters and NHR were significantly higher in the patients who had a TT (p=0.03, 0.04). MFR was significantly higher in the patients who had an LO than in the controls (p=0.02). As compared with the patients who had an LO, MPT was significantly shorter (p=0.0004) and MFR and NHR were significantly higher (p=0.004, 0.03) in the patients with a TT. In the patients who had a TT, the MPT immediately after the surgery was significantly longer in the patients who had simultaneously neck dissection (ND) in comparison with the patients who did not have ND. However, all these differences gradually decreased and were not significant at one month after surgery. Our results suggest that TT and ND have a distinct impact on voice quality after surgical treatment for thyroid cancer, probably due to slight and transient nerve conduction disorders induced by the manipulation around recurrent laryngeal nerves and/or laryngeal edema induced by the disturbance of venous and lymphatic drainages. However, these changes appear to be temporary, lasting only a few weeks.

음도 고정 유무에 따른 공기역학, 음성효율성 및 성대접촉률 차이

The aerodynamic characteristics (subglottal pressure (Ps) and mean airflow rate (MFR)), fundamental frequency (Fo), intensity (I), vocal efficiency (VE), and closed quotient (CQ) were compared during a sustained vowel /o/ sound under three conditions: in a comfortable loudness and pitch level (condition 1), in a maximum loudness level with a fixed pitch (condition 2), and in a maximum loudness level without a fixed pitch (condition 3). Also, multiple regression analyses were done to measure the aerodynamic characteristics affect on the VE and the CQ in each condition. The results showed the Fo, Ps, MFR, VE, and CQ increased as I increased with and without fixed pitch. Most notably, VE in condition 3 was the highest of all the conditions, but CQ was not very high. By the results of multiple regression analysis, VE was significantly affected by I and Ps in all conditions; Fo was the other main key for affecting VE in high pitch. However, none of the aerodynamic characteristics significantly affected CQ. As I increases, Fo should be increased by increasing Ps and VE. Therefore, researchers should consider and specify an a priori to Fo, Ps, and I when measuring VE to examine the complex and delicate vocal mechanism.

Laryngeal aerodynamic analysis of vocal nodules

The present study is aimed to investigate the effects of vocal nodules on the aerodynamic analysis of the voice. The study included twelve females with normal laryngeal and respiratory functions and twelve age, gender and language matched females with bilateral vocal nodules within the age group of 18-40 years. All participants were subjected to non-invasive aerodynamic analysis using Aeroview 1.4.4 version (Glottal Enterprises Inc, USA). The participants were instructed to produce the CV syllable train papapapa into the circumvented mask at comfortable pitch and loudness. The recorded stimuli were analyzed to obtain laryngeal aerodynamic measures such as estimated subglottic pressure, mean airflow rate, laryngeal airway resistance, and laryngeal airway conductance. Mean and standard deviation for all the four laryngeal aerodynamic measures were calculated separately for both control and clinical groups. The results revealed significant effect of voice on laryngeal measures such as estimated subglottic pressure and mean airflow rate. Thus, results suggest that indirect measurement of laryngeal aerodynamic parameters are effective and essential investigative tools in assessment of vocal nodules.

Glottal configuration in unilaterally paralyzed larynx and vocal function

Conclusions: Three different types of glottal configuration in unilaterally paralyzed larynx were proposed by utilizing three-dimensional computed tomographic (3DCT) images. This new classification might facilitate understanding of the behavior of the affected vocal fold in terms of vocal function. Objectives: To develop a classification of glottal configuration in unilateral vocal fold paralysis (UVFP) based on the thickness and location of the vocal folds utilizing 3DCT and to compare each type of configuration with vocal function. Methods: Thirty-seven consecutive patients with UVFP underwent CT during phonation and inhalation. 3D endoscopic and coronal images on two occasions were produced. Maximum phonation time and mean airflow rate were also measured. Results: Three types of glottal configuration were proposed. The thickness of the affected vocal fold during phonation was equal to or slightly thinner than the healthy fold in 10 patients (type A). The affected fold of the remaining 27 was thin during phonation; they were further classified into types B and C. In type B, the affected fold remained thin during phonation and inhalation (n = 12). Type C was allocated to those showing one or two paradoxical movements of the affected fold (n = 15). Those with type A showed significantly better vocal function.

Sulcus vocalis: excision, primary suture and medialization laryngoplasty: personal experience with 44 cases

This is a prospective, cohort study to present personal experience on excision of sulcus, primary suture of defect and medialization laryngoplasty. An article about this subject is not present in medical literature. Forty-four patients with sulcus vocalis who were operated on by excision, primary suture of epithelial defect and medialization laryngoplasty were included. Pre- and postoperative evaluations included GRBAS, VHI-30, stroboscopy, aerodynamic and acoustic analysis. Grade, roughness and breathiness of GRBAS were significantly better postoperatively (p<0.05), whereas asthenia and strain were not (p>0.05). All VHI-30 results decreased significantly after surgery (p<0.01). Glottal closure and mucosal wave amplitude during stroboscopy improved significantly postoperatively (p<0.05), whereas symmetry and periodicity did not (p>0.05). Maximum phonation time, mean airflow rate, mean efficiency and mean pressure of aerodynamic analysis improved significantly after surgery (p<0.05). However, mean resistance and mean power were not significantly different (p>0.05). All parameters, except F (0) and soft phonation index during acoustic analysis with /a/, and except F (0), voice turbulence index and soft phonation index during acoustic analysis with constant phrase improved significantly after surgery (p<0.05). Surgical treatments of sulcus vocalis are not satisfactory enough, yet. Excision of sulcus, primary suture of epithelial defect and medialization laryngoplasty is one of the successful surgical options. Intact vocal ligament at the bottom of sulcus is a good prognostic sign for good postoperative voice result. Success appears to depend on how long, how wide and how deep sulcus is. Good patient selection may increase the percentage of happy patients.

Analysis of Pitch Range After Arytenoid Adduction by Fenestration Approach Combined With Type I Thyroplasty for Unilateral Vocal Fold Paralysis

The purpose of this study was to determine the postoperative pitch range acquired in cases of unilateral vocal fold paralysis, as well as factors affecting outcomes. We analyzed 39 cases of unilateral vocal fold paralysis for which surgery was performed between January 2006 and January 2009 and for which pitch ranges and the items listed below were measured preoperatively and 1 year postoperatively. Arytenoid adduction (AA) and type I thyroplasty were performed simultaneously in all cases regardless of preoperative severity. AA was performed by the fenestration approach as previously reported. In this procedure, the cricoarytenoid and cricothyroid joints are not released. Correlations between pitch range acquired postoperatively and the following items were examined: (1) pre- and postoperative maximum phonation time (MPT), (2) pre- and postoperative mean airflow rate (MFR), and (3) preoperative pitch range. Furthermore, patients were surveyed regarding their ability to sing after surgery, and the pitch range cutoff value dividing ability and inability to sing was calculated. Pitch range increased significantly from 3±4.47 halftones (mean ± standard deviation) preoperatively to 17.5±5.80 halftones postoperatively. Preoperative MPT, MFR, and pitch range did not correlate with postoperative pitch range. Postoperatively, only MPT correlated with the width of postoperative pitch range. Twenty-three of 39 subjects (59%) responded that they were able to sing, and the pitch range cutoff value dividing the two groups was 22 halftones. AA and type I thyroplasty significantly expanded postoperative pitch range. There was no correlation between preoperative severity and width of pitch range acquired postoperatively.

Longitudinal analysis of voice quality in patients with early glottic cancer after transoral laser microsurgery

We conducted longitudinal voice evaluations in patients with early glottic cancer who underwent transoral laser microsurgery (TLM) to determine the time to stability. Twenty-five patients underwent TLM, including 13 limited cordectomies (type I and type II) and 12 extended cordectomies (type III to type IV). Multidimensional voice evaluations were performed before treatment and at 1, 3, 6, and 12 months after treatment. Voice parameters of asthenicity, strain, mean airflow rate (MFR), voice handicap index (VHI)-functional, VHI-physical, and VHI-total scores improved in all patients. Most patients had improved 6 months after TLM. Patients with extended cordectomy showed higher breathiness, MFR, VHI-functional, and VHI-total scores. Healing was complete in all cases by 6 months and in a majority of cases (76%) by 3 months. Voice quality achieved stability 6 months after TLM. Comparing treatment outcomes and surgical intervention are not recommended within 6 months of surgery.

Arytenoid adduction combined with medialization laryngoplasty under general anesthesia using a laryngeal mask airway

PurposeLaryngeal framework surgery is usually performed under local anesthesia but cannot be tolerated by some patients. To develop a new procedure for these patients, we evaluated voice outcomes after arytenoid adduction combined with medialization laryngoplasty under general anesthesia using a laryngeal mask airway (LMA) for unilateral vocal cord paralysis. Materials and MethodsEleven consecutive patients with severe unilateral vocal cord paralysis, with a maximum phonation time of less than 5 seconds, underwent arytenoid adduction combined with medialization laryngoplasty under general anesthesia using an LMA. Each paralyzed vocal cord was observed by intraoperative videolaryngoscopy. The vocal cord was moved to the position where the best vocal outcome could be expected, according to 3 parameters obtained from glottal images. ResultsAll patients achieved a maximum phonation time of more than 11 seconds. The mean airflow rate, which ranged from 550 to 1000 mL/s before surgery, improved to less than 390 mL/s. Perceptual evaluation using the grade, roughness, breathiness, asthenia and strain scale also improved significantly. ConclusionsThese results were equivalent to those of previous reports of surgeries performed under local anesthesia. Intraoperative endoscopic vocal cord observation through the LMA may have contributed to the positive results.

Laryngeal Electromyography-Guided Hyaluronic Acid Vocal Fold Injection for Unilateral Vocal Fold Paralysis—Preliminary Results

The purpose of this study is to investigate the feasibility of using an injectable needle electrode to guide hyaluronic acid (HA) vocal fold injection (VFI) during laryngeal electromyography (LEMG) for unilateral vocal fold paralysis (UVFP). Prospective study. From March to June 2010, 20 UVFP patients received LEMG examination at our clinic. Before completion of LEMG, 1.0 cc of HA (Restylane Perlane(®); Q-Med, Uppsala, Sweden) was injected via a 26-gauge monopolar injectable needle electrode into paralyzed thyroarytenoid muscle. After injection, 20 patients completed 3-months follow-up and 16 patients completed 6-months follow-up. The data before, 1 week, 3 months, and 6 months after injection, including the normalized glottal gap area (NGGA) from videostroboscopy, maximal phonation time (MPT), mean airflow rate (MAFR), phonation quotient (PQ), perceptual evaluation of voice (grade, roughness, breathiness, asthenia, strain [GRBAS] scale), Voice Handicap Index (VHI), and self-grading of choking (grade 1-7), were analyzed by the Wilcoxon signed rank test. All of the patients completed the procedure without complications. After injection, mean NGGA was significantly reduced from 8.28 units to 0.52 units (1 week), 1.79 units (3 months), and 1.36 units (6 months). The mean MPT was prolonged from 5.66 seconds to 11.73, 11.25, and 11.93 seconds, respectively. VHI was reduced from 76.05 to 38.10, 37.40 and 35.00, respectively. Other analyzed data (PQ, MAFR, GRBAS scale, and choking severity) also showed statistically significant improvement. LEMG-guided HA VFI provides UVFP patients with neuromuscular function evaluation and treatment in one step. This clinical technique is feasible, and the short-term results are satisfactory.

Laryngeal Aerodynamic Analysis in Assisting With the Diagnosis of Muscle Tension Dysphonia

To estimate the aerodynamic multiparameters for patients with muscular tension dysphonia (MTD) and evaluate voice aerodynamic analysis for assisting the diagnosis of this disorder. A prospective study. Voice aerodynamic parameters, including subglottal pressure (SGP) level, glottal resistance (GR), mean airflow rate (MFR), and maximum phonation time (MPT), for 26 MTD patients and 27 normal adults were analyzed using receiver operating characteristics (ROC) analysis and multivariate logistic regression. For male samples, MTD patients had higher SGP (P=0.001), higher GR (P=0.012), lower MFR (P=0.042), and shorter MPT (P=0.027), whereas for female samples, the difference between cases and controls was statistically significant only in SGP (P<0.001) and MPT (P<0.001). ROC analysis showed that the threshold of 8.175 cm H(2)O for SGP achieved a good classification for MTD, with an adequate sensitivity (76.9%) and the perfect specificity (100%). Finally, multivariate logistic regression established a credible model (with SGP and MPT as the predictors) for classifying MTD, with a 92.5% percentage correct. This analysis indicates that aerodynamics evaluation could help the diagnosis of MTD patients, jointly with medical history scrutiny, physical examination, fibrolaryngoscopy, and/or videoendostroboscopy.

A new and less invasive procedure for arytenoid adduction surgery

Arytenoid adduction (AA) is the most effective procedure for improving voice function in patients affected by unilateral vocal fold paralysis (UVFP), but it is often associated with severe complications following airway obstruction. The aim of this study is to describe a new and less invasive AA surgical procedure termed endoscopic-assisted AA surgery (EAAS) and to evaluate its voice outcomes. We demonstrated this method using extirpated larynges from three laryngeal cancer patients. Ten patients with severe UVFP underwent EAAS alone or combined with type I thyroplasty or lipoinjection laryngoplasty. EAAS involves the placement of permanent adducting sutures around the muscular process (MP) of the arytenoid cartilage using two needles, a penetration needle and a loop needle, under endoscopic guidance. To define the anatomic position of the MP for safer needle insertion, the location of the MP was measured relative to three landmarks on computed tomography/X-ray images of the larynges and in resected larynges. For all patients with UVFP, the maximum phonation time, mean airflow rate, and three acoustic analysis parameters were measured before and after EAAS. The values of the three variables were similar in all cases. Most patients achieved a maximum phonation time of more than 10 seconds and a mean airflow rate of less than 200 mL/second. All three acoustic analysis parameters were significantly improved after surgery. EAAS is a simple and effective arytenoid rotation procedure.

Nerve-Muscle Pedicle Flap Implantation Combined With Arytenoid Adduction

To describe a new technique of nerve-muscle pedicle (NMP) flap implantation combined with arytenoid adduction (AA) to treat dysphonia due to unilateral vocal fold paralysis and to examine postoperative vocal function. Retrospective review of clinical records. Tertiary academic center. Twenty-two consecutive patients underwent NMP flap implantation with AA and were followed up short term over a period of 1 to 6 months (mean, 2.9 months) and long term over a period of 7 to 36 months (mean, 21.4 months). An NMP flap was made using an ansa cervicalis branch and a piece of the sternohyoid muscle. A window was opened in the thyroid ala at the level of the vocal fold. Then, AA was performed and the NMP flap was securely implanted onto the thyroarytenoid muscle through the window under microscopic guidance. The maximum phonation time, mean airflow rate, pitch range, and acoustic parameters (jitter, shimmer, and harmonics to noise ratio) were evaluated before surgery and twice after surgery. All parameters improved significantly after surgery (P < .01). The measurements for maximum phonation time, mean airflow rate, and harmonics to noise ratio were within normal ranges after surgery. Furthermore, the maximum phonation time and jitter were significantly improved after long-term follow-up compared with early postoperative measurements (P < .01 and P < .05, respectively). Precise harvest of an NMP flap and its placement directly onto the thyroarytenoid muscle combined with AA provided excellent vocal function. The NMP method may have played a certain role in the improvement of postoperative vocal function, although further study with electromyographic examination is required to clarify the innervation status of the thyroarytenoid muscle.