Minimizing Thermal Damage During Thulium Laser-Assisted Partial Arytenoidectomy: Pulsed Versus Continuous Cutting in an Ex-Vivo Calf Model

OBJECTIVES

The 2 µm-wavelength thulium laser is an effective cutter during partial arytenoidectomy, but thermal trauma can damage adjacent laryngeal tissue. Pulsing laser energy may reduce trauma when compared to continuous-wave cutting. This study measured temperature changes, thermal trauma, and time to complete partial arytenoidectomy, with and without pulsing, in an ex-vivo calf model.

METHODS

Tissue temperature and time to complete a trans-cartilaginous cut were measured during partial arytenoidectomy on ex-vivo calf vocal folds (N = 24) using a thulium laser in continuous-wave (CW, N = 12) and pulsed-wave (PW, N = 12) modes. Energy was 5 W for CW and PW cuts; pulse-widths were 250, 500, and 750 ms. Thermal damage was analyzed histologically by measuring the depth of lactate dehydrogenase (LDH) inactivation perpendicular to the laser-cut edge at the vocal process. Paired t-tests compared CW and PW modes.

RESULTS

Change in temperature was lower using CW (6.5°C) compared to PW modes (250 ms = 18°; 500 ms = 16°; 750 = 19°; P < .05). Trans-cartilaginous cuts were completed faster using CW (37 seconds) compared to PW (250 ms = 136 seconds; 500 ms = 61 seconds; 750 = 44 seconds; P < .05), and both modes delivered the same total Joules. The average depth of LDH depletion (thermal damage) was similar for all cuts.

CONCLUSIONS

1. Thulium laser cuts in continuous-mode unexpectedly produced less tissue heating yet created similar thermal damage than pulsed-mode cuts during simulated partial arytenoidectomy. 2. Trans-cartilaginous cuts were completed significantly faster in continuous-mode as compared to pulsed-mode cutting. 3. Pulsing the thulium laser does not minimize thermal damage compared to continuous wave cutting during thulium laser-assisted partial arytenoidectomy.

Lions and brown bears colonized North America in multiple synchronous waves of dispersal across the Bering Land Bridge

The Bering Land Bridge connecting North America and Eurasia was periodically exposed and inundated by oscillating sea levels during the Pleistocene glacial cycles. This land connection allowed the intermittent dispersal of animals, including humans, between Western Beringia (far northeast Asia) and Eastern Beringia (northwest North America), changing the faunal community composition of both continents. The Pleistocene glacial cycles also had profound impacts on temperature, precipitation and vegetation, impacting faunal community structure and demography. While these palaeoenvironmental impacts have been studied in many large herbivores from Beringia (e.g., bison, mammoths, horses), the Pleistocene population dynamics of the diverse guild of carnivorans present in the region are less well understood, due to their lower abundances. In this study, we analyse mitochondrial genome data from ancient brown bears (Ursus arctos; n = 103) and lions (Panthera spp.; n = 39), two megafaunal carnivorans that dispersed into North America during the Pleistocene. Our results reveal striking synchronicity in the population dynamics of Beringian lions and brown bears, with multiple waves of dispersal across the Bering Land Bridge coinciding with glacial periods of low sea levels, as well as synchronous local extinctions in Eastern Beringia during Marine Isotope Stage 3. The evolutionary histories of these two taxa underline the crucial biogeographical role of the Bering Land Bridge in the distribution, turnover and maintenance of megafaunal populations in North America.

Changes in the Daily Phonotrauma Index Following the Use of Voice Therapy as the Sole Treatment for Phonotraumatic Vocal Hyperfunction in Females

Purpose The aim of this study was to use the Daily Phonotrauma Index (DPI) to quantify group-based changes in the daily voice use of patients with phonotraumatic vocal hyperfunction (PVH) after receiving voice therapy as the sole treatment. This is part of an ongoing effort to validate an updated theoretical framework for PVH. Method A custom-designed ambulatory voice monitor was used to collect 1 week of pre- and posttreatment data from 52 female patients with PVH. Normative weeklong data were also obtained from 52 matched controls. Each week was represented by the DPI, which is a combination of neck-surface acceleration magnitude skewness and the standard deviation of the difference between the first and second harmonic magnitudes. Results Compared to pretreatment, the DPI statistically decreased towards normal in the patient group after treatment (Cohen's d = -0.25). The posttreatment patient group's DPI was still significantly higher than the control group (d = 0.68). Conclusions The DPI showed the pattern of improved ambulatory voice use in a group of patients with PVH following voice therapy that was predicted by the updated theoretical framework. Per the prediction, voice therapy was associated with a decreased potential for phonotrauma in daily voice use, but the posttreatment patient group data were still significantly different from the normative control group data. This posttreatment difference is interpreted as reflecting the impact on voice use of the persistence of phonotrauma-induced structural changes to the vocal folds. Further validation of the DPI is needed to better understand its potential clinical use.

Surgeon Positioning During Awake Laryngeal Surgery: An Ergonomic Analysis

OBJECTIVES

While it is acknowledged that otolaryngologists performing microlaryngeal surgery can develop musculoskeletal symptoms due to suboptimal body positioning relative to the patient, flexible laryngoscopy and awake laryngeal surgeries (ALSs) can also pose ergonomic risk. This prospective study measured the effects of posture during ergonomically good and bad positions during laryngoscopy using ergonomic analysis, skin-surface electromyography (EMG), and self-reported pain ratings.

STUDY DESIGN

Prospective cohort study.

METHODS

Eight participants trained in laryngoscopy assumed four ergonomically distinct standing positions (side/near, side/far, front/near, front/far) at three different heights (neutral-top of patient's head in line with examiner's shoulder, high-6 inches above neutral, and low-6 inches below neutral) in relation to a simulated patient. Participants' postures were analyzed using the validated Rapid Upper Limb Assessment (RULA, 1 [best] to 7 [worst]) tool for the 12 positions. Participants then simulated ALS for 10 minutes in a bad position (low-side-far) and a good position (neutral-front-near) with 12 EMG sensors positioned on the limbs and torso.

RESULTS

The position with the worst RULA score was the side/near/high (7.0), and the best was the front/near/neutral (4.5). EMG measurements revealed significant differences between simulated surgery in the bad and good positions, with bad position eliciting an average of 206% greater EMG root-mean-squared magnitude across all sampled muscles compared to the good posture (paired t-test, df = 7, P < .01), consistent with self-reported fatigue/pain when positioned poorly.

CONCLUSION

Quantitative and qualitative measurements demonstrate the impact of surgeon posture during simulated laryngoscopy and suggest ergonomically beneficial posture that should facilitate ALSs.

LEVEL OF EVIDENCE

3 Laryngoscope, 2021.

Differences in Daily Voice Use Measures Between Female Patients With Nonphonotraumatic Vocal Hyperfunction and Matched Controls

Purpose The purpose of this study was to obtain a more comprehensive understanding of the pathophysiology and impact on daily voice use of nonphonotraumatic vocal hyperfunction (NPVH). Method An ambulatory voice monitor collected 1 week of data from 36 patients with NPVH and 36 vocally healthy matched controls. A subset of 11 patients with NPVH were monitored after voice therapy. Daily voice use measures included neck-skin acceleration magnitude, fundamental frequency (f _o), cepstral peak prominence (CPP), and the difference between the first and second harmonic magnitudes (H1-H2). Additional comparisons included 118 patients with phonotraumatic vocal hyperfunction (PVH) and 89 additional vocally healthy controls. Results The NPVH group, compared to the matched control group, exhibited increased f _o (Cohen's d = 0.6), reduced CPP (d = -0.9), and less positive H1-H2 skewness (d = -1.1). Classifiers used CPP mean and H1-H2 mode to maximally differentiate the NPVH and matched control groups (area under the receiver operating characteristic curve of 0.78). Classifiers performed well on unseen data: the logit decreased in patients with NPVH after therapy; ≥ 85% of the control and PVH groups were identified as "normal" or "not NPVH," respectively. Conclusions The NPVH group's daily voice use is less periodic (CPP), is higher pitched (f _o), and has less abrupt vocal fold closure (H1-H2 skew) compared to the matched control group. The combination of CPP mean and H1-H2 mode appears to reflect a pathophysiological continuum in NPVH patients of inefficient phonation with minimal potential for phonotrauma. Further validation of the classification model is needed to better understand potential clinical uses. Supplemental Material https://doi.org/10.23641/asha.14390771.

Optimal Arytenoid Position in Laryngeal Framework Surgery: An Anatomic Human Larynx Study

OBJECTIVES

The purpose of this study was to better understand the effects of stitch placement on arytenoid medialization by measuring normative cricoarytenoid joint anatomy and changes in arytenoid position when varying arytenopexy stitch configuration.

METHODS

This adult human larynx study was done in two parts. First, measurements of the cricoid and arytenoid cartilage anatomy relevant to cricoarytenoid joint function were made in 45 preserved larynges (26 male (M), 19 female (F)) using digital calipers. Second, the arytenoids of six fresh larynges ( three M, three F) were sutured to the cricoid using various arytenopexy-stitch placements ranging from inferior-lateral to superior-medial, and the resulting arytenoid positions were compared by measuring medial displacement of the arytenoid body and change in glottal configuration from macro still images using Image J. Paired t-tests were used to compare the results.

RESULTS

Cartilage and joint facet dimensions showed differences between males (M) and females (F). Cricoid facet lengths averaged 9.3 mm (M) and 7.1 mm (F), and widths averaged 4.9 mm (M) and 4.0 mm (F). The arytenoid facet widths averaged 10.5 mm (M) and 9.7 mm (F). Average distances between cricoid facets were 11.8 mm for both males and females. Securing the arytenoid superior-medially on the cricoid facet produced more medialization (2.2 mm vs 1.0 mm, P < .001) and better glottic aperture configuration (9.5° vs 2.7°, P < .001) than securing the arytenoid inferior-laterally on the facet.

CONCLUSIONS

Anatomic consistency in cricoarytenoid anatomy provides reliable surgical landmarks for ideal placement of an arytenopexy suture to optimally reposition the arytenoid cartilage. Optimal arytenoid medialization can be accurately reproduced with an arytenopexy-suture that is placed superior-medially on the cricoid facet.

LEVEL OF EVIDENCE

NA Laryngoscope, 2021.

Differences Between Female Singers With Phonotrauma and Vocally Healthy Matched Controls in Singing and Speaking Voice Use During 1 Week of Ambulatory Monitoring

Purpose Previous ambulatory voice monitoring studies have included many singers and have combined speech and singing in the analyses. This study applied a singing classifier to the ambulatory recordings of singers with phonotrauma and healthy controls to determine if analyzing speech and singing separately would reveal voice use differences that could provide new insights into the etiology and pathophysiology of phonotrauma in this at-risk population. Method Forty-two female singers with phonotrauma (vocal fold nodules or polyps) and 42 healthy matched controls were monitored using an ambulatory voice monitor. Weeklong statistics (average, standard deviation, skewness, kurtosis) for sound pressure level (SPL), fundamental frequency, cepstral peak prominence, the magnitude ratio of the first two harmonics (H₁-H₂ ), and three vocal dose measures were computed from the neck surface acceleration signal and separated into singing and speech using a singing classifier. Results Mixed analysis of variance models found expected differences between singing and speech in each voice parameter, except SPL kurtosis. SPL skewness, SPL kurtosis, and all H₁-H₂ distributional parameters differentiated patients and controls when singing and speech were combined. Interaction effects were found in H₁-H₂ kurtosis and all vocal dose measures. Patients had significantly higher vocal doses in speech compared to controls. Conclusions Consistent with prior work, the pathophysiology of phonotrauma in singers is characterized by more abrupt/complete glottal closure (decreased mean and variation for H₁-H₂ ) and increased laryngeal forces (negatively skewed SPL distribution) during phonation. Application of a singing classifier to weeklong data revealed that singers with phonotrauma spent more time speaking on a weekly basis, but not more time singing, compared to controls. Results are used as a basis for hypothesizing about the role of speaking voice in the etiology of phonotraumatic vocal hyperfunction in singers.

Changes in a Daily Phonotrauma Index After Laryngeal Surgery and Voice Therapy: Implications for the Role of Daily Voice Use in the Etiology and Pathophysiology of Phonotraumatic Vocal Hyperfunction

Purpose This study attempts to gain insights into the role of daily voice use in the etiology and pathophysiology of phonotraumatic vocal hyperfunction (PVH) by applying a logistic regression-based daily phonotrauma index (DPI) to predict group-based improvements in patients with PVH after laryngeal surgery and/or postsurgical voice therapy. Method A custom-designed ambulatory voice monitor was used to collect 1 week of pre- and postsurgery data from 27 female patients with PVH; 13 of these patients were also monitored after postsurgical voice therapy. Normative weeklong data were obtained from 27 matched controls. Each week was represented by the DPI, standard deviation of the difference between the first and second harmonic amplitudes (H1-H2). Results Compared to pretreatment, the DPI significantly decreased in the patient group after surgery (Cohen's d effect size = -0.86) and voice therapy (d = -1.06). The patient group DPI only normalized after voice therapy. Conclusions The DPI produced the expected pattern of improved ambulatory voice use across laryngeal surgery and postsurgical voice therapy in a group of patients with PVH. The results were interpreted as providing new objective information about the role of daily voice use in the etiology and pathophysiology of PVH. The DPI is viewed as an estimate of potential vocal fold trauma that relies on combining the long-term distributional characteristics of two parameters representing the magnitude of phonatory forces (neck-surface acceleration magnitude) and vocal fold closure dynamics (H1-H2). Further validation of the DPI is needed to better understand its potential clinical use.

Patient-Reported Factors Associated with the Onset of Hyperfunctional Voice Disorders

OBJECTIVES

Prevention, diagnosis, and treatment of hyperfunctional voice disorders would be improved by better understanding their etiological contributing factors. Therefore, this study estimated the prevalence of etiological factors using self-reported data about disorder onset from a large cohort of patients with Phonotraumatic Vocal Hyperfunction (PVH) and Non-Phonotraumatic Vocal Hyperfunction (NPVH).

METHODS

Retrospective chart review extracted the self-reported rate (gradual, sudden) and events associated (voice use, anxiety/stress, upper respiratory infection [URI]) with disorder onset from 1,577 patients with PVH and 979 patients with NPVH.

RESULTS

Both patient groups reported a gradual onset more than a sudden onset. Voice use was the most frequently reported event for PVH and the NPVH group self-reported all three events at equal frequency. The largest PVH subgroups were associated with voice use while the NPVH subgroups were associated with only voice use, only URI, or only anxiety/stress.

CONCLUSION

The results support the general clinical view that PVH is most strongly related to the gradual accumulated effects of phonotrauma, while NPVH has a more heterogeneous etiology. The identified PVH and NPVH subgroups may have clinical relevance and future work could investigate differences in treatment and outcomes among these subgroups.

Estimation of Subglottal Pressure From Neck Surface Vibration in Patients With Voice Disorders

Purpose Given the established linear relationship between neck surface vibration magnitude and mean subglottal pressure (Ps) in vocally healthy speakers, the purpose of this study was to better understand the impact of the presence of a voice disorder on this baseline relationship. Method Data were obtained from participants with voice disorders representing a variety of glottal conditions, including phonotraumatic vocal hyperfunction, nonphonotraumatic vocal hyperfunction, and unilateral vocal fold paralysis. Participants were asked to repeat /p/-vowel syllable strings from loud-to-soft loudness levels in multiple vowel contexts (/pa/, /pi/, /pu/) and pitch levels (comfortable, higher than comfortable, lower than comfortable). Three statistical metrics were computed to analyze the regression line between neck surface accelerometer (ACC) signal magnitude and Ps within and across pitch, vowel, and voice disorder category: coefficient of determination (r 2), slope, and intercept. Three linear mixed-effects models were used to evaluate the impact of voice disorder category, pitch level, and vowel context on the relationship between ACC signal magnitude and Ps. Results The relationship between ACC signal magnitude and Ps was statistically different in patients with voice disorders than in vocally healthy controls; patients exhibited higher levels of Ps given similar values of ACC signal magnitude. Negligible effects were found for pitch condition within each voice disorder category, and negligible-to-small effects were found for vowel context. The mean of patient-specific r 2 values was .63, ranging from .13 to .92. Conclusions The baseline, linear relationship between ACC signal magnitude and Ps is affected by the presence of a voice disorder, with the relationship being participant-specific. Further work is needed to improve ACC-based prediction of Ps, across treatment, and during naturalistic speech production.

Differences in Weeklong Ambulatory Vocal Behavior Between Female Patients With Phonotraumatic Lesions and Matched Controls

Purpose Previous work using ambulatory voice recordings has shown no differences in average vocal behavior between patients with phonotraumatic vocal hyperfunction and matched controls. This study used larger groups to replicate these results and expanded the analysis to include distributional characteristics of ambulatory voice use and measures indicative of glottal closure. Method Subjects included 180 adult women: 90 diagnosed with vocal fold nodules or polyps and 90 age-, sex-, and occupation-matched controls with no history of voice disorders. Weeklong summary statistics (average, variability, skewness, kurtosis) of voice use were computed from neck-surface acceleration recorded using an ambulatory voice monitor. Voice measures included estimates of sound pressure level (SPL), fundamental frequency (f _o), cepstral peak prominence, and the difference between the first and second harmonic magnitudes (H1-H2). Results Statistical comparisons resulted in medium-large differences (Cohen's d ≥ 0.5) between groups for SPL skewness, f _o variability, and H1-H2 variability. Two logistic regressions (theory-based and stepwise) found SPL skewness and H1-H2 variability to classify patients and controls based on their weekly voice data, with an area under the receiver operating characteristic curve of 0.85 and 0.82 on training and test sets, respectively. Conclusion Compared to controls, the weekly voice use of patients with phonotraumatic vocal hyperfunction reflected higher SPL tendencies (negatively skewed SPL) with more abrupt glottal closure (reduced H1-H2 variability, especially toward higher values). Further work could examine posttreatment data (e.g., after surgery and/or therapy) to determine the extent to which these differences are associated with the etiology and pathophysiology of phonotraumatic vocal fold lesions.

The Use of 532-Nanometer-Pulsed Potassium-Titanyl-Phosphate (KTP) Laser in Laryngology: A Systematic Review of Current Indications, Safety, and Voice Outcomes

OBJECTIVE

To investigate the indications, efficacy, safety, and outcomes of potassium-titanyl-phosphate (KTP) laser procedures for treatment of laryngeal disease.

METHODS

PubMed, Cochrane Library, and Scopus were searched for studies providing information about the indications, efficacy, and safety of both in-office and operative suspension microlaryngoscopy KTP laser procedure in treatment of laryngeal disease. Diagnostic criteria and clinical outcome evaluation of included studies were analyzed using Preferred Reporting Items for Systematic Reviews and Meta-Analyses criteria.

RESULTS

Of the initial screened 140 papers, 17 met our inclusion criteria. Six papers involved KTP laser procedures for benign and malignant vocal fold lesions in suspension microlaryngoscopy only, 10 papers focused on only in-office KTP laser procedures for benign vocal fold lesions, and 1 paper included both in-office and suspension microlaryngoscopy procedures. The following lesions may be considered as indications for KTP laser procedures: Reinke's edema, sulcus vocalis, vocal fold hemorrhage, polyp, granuloma, cyst, scar, papillomatosis, dysplasia, leukoplakia, and early vocal fold malignancies. Irrespective of the types of procedure (in-office vs suspension microlaryngoscopy), the KTP laser is associated with a low complication rate and overall good vocal fold vibration recovery. There is an important heterogeneity among studies concerning laser settings, indications, and outcomes used for the assessment of treatment effectiveness. There are no controlled studies directly comparing KTP laser with other lasers (ie, carbon dioxide laser).

CONCLUSION

The use of KTP laser procedures for treatment of laryngeal disease has increased over the past decade, especially for office-based management of vocal fold lesions. Future controlled studies are needed to compare the safety and outcomes of the KTP laser to other techniques.

Efficacy of Videostroboscopy and High-Speed Videoendoscopy to Obtain Functional Outcomes From Perioperative Ratings in Patients With Vocal Fold Mass Lesions

OBJECTIVES

A major limitation of comparing the efficacy of videostroboscopy (VS) and high-speed videoendoscopy (HSV) is the lack of an objective reference by which to compare the functional assessment ratings of the two techniques. For patients with vocal fold mass lesions, intraoperative measures of lesion size and depth may serve as this objective reference. This study compared the relationships between the pre- to postoperative change in VS and HSV visual-perceptual ratings to intraoperative measures of lesion size and depth.

DESIGN

Prospective visual-perceptual study with intraoperative measures of lesion size and depth.

METHODS

VS and HSV samples were obtained preoperatively and postoperatively from 28 patients with vocal fold lesions and from 17 vocally healthy controls. Two experienced clinicians rated amplitude, mucosal wave, vertical phase difference, left-right phase asymmetry, and vocal fold edge on a visual-analog scale using both imaging techniques. The change in perioperative ratings from VS and HSV was compared between groups and correlated to intraoperative measures of lesion size and depth.

RESULTS

HSV was as reliable as VS for ratings of amplitude and edge, and substantially more reliable for ratings of mucosal wave and left-right phase asymmetry. Both VS and HSV had mild-moderate correlations between change in perioperative ratings and intraoperative measures of lesion area. Change in function could be obtained in more patients and for more parameters using HSV than VS. Group differences were noted for postoperative ratings of amplitude and edge; however, these differences were within one level of the visual-perceptual rating scale. The presence of asynchronicity in VS recordings renders vibratory features either uninterpretable or potentially distorted and thus should not be rated.

CONCLUSIONS

Amplitude and edge are robust vibratory measures for perioperative functional assessment, regardless of imaging modality. HSV is indicated for evaluation of subepithelial lesions or if asynchronicity is present in the VS image sequence.

Carbon debris and fiber cleaving: Effects on potassium-titanyl-phosphate laser energy and chorioallantoic membrane model vessel coagulation

OBJECTIVES/HYPOTHESIS

Photoangiolytic precision afforded by the 532-nm potassium-titanyl-phosphate (KTP) laser relies on predictable energy delivery. Inadequate energy output can cause vessel rupture, and excessive energy can cause thermal damage. The quality of the cleaved surface and carbon deposits from ablated tissue are two factors that could negatively impact fiber performance. The effects of these on energy output and blood vessel coagulation were assessed using a chorioallantoic membrane (CAM) model.

STUDY DESIGN

Comparative analysis.

METHODS

Laser fibers with carbon debris, optimal fiber cleaving, and suboptimal cleaving were inspected at three times magnification, and the light dispersion pattern of each fiber was rated. The average energy output from consecutive pulses through each fiber configuration was recorded. The effect of these fiber conditions on clinical efficacy was estimated by measuring vessel coagulation versus rupture in the CAM model. Repeated measures analysis of variance compared results.

RESULTS

Carbon debris and suboptimal cleaving resulted in decreased energy output in comparison to optimal cleaving ([-Δ244 mJ, d = 4.31, P < .001] and [-Δ195 mJ, d = 6.04, P < .001]). Optimal cleaving resulted in immediate coagulation of vessels. Fibers with suboptimal cleaving and carbon debris had unpredictable outcomes, requiring multiple pulses for coagulation or causing vessel rupture.

CONCLUSIONS

KTP laser fiber function is significantly affected by fiber tip condition. Carbon debris and suboptimal cleaving create significant attenuation of energy, which results in an unpredictable angiolytic effect, as demonstrated by increased vessel rupture in the CAM model. Optimal recleaving of KTP laser fibers restores prior energy output and predictable coagulation. Care should be taken to avoid carbon debris on laser-fiber tips and to cleave fibers properly.

LEVEL OF EVIDENCE

NA Laryngoscope, 129:2244-2248, 2019.

Glottic Stenosis: An Anatomic Analysis and New Treatment With a Self-Retaining Interarytenoid Spring

Introduction:

Endotracheal (ET) intubation is a common cause of acquired glottic stenosis. Severe cases often require an irreversible arytenoidectomy/cordectomy, which typically results in poor voice quality. Adult human cadaver larynges were studied to gain insights about ET tube–induced posterior glottic injuries, hoping to create a less invasive remedy.

Study Design:

Human cadaver investigation and case reports.

Methods:

Microlaryngeal assessments were done on 10 human cadaver larynges (5 men, 5 women) with and without ET tubes. After supracricoid soft tissue resection, measurements were obtained, including the distance between the outer diameter of the ET tube and the medial aspect of the cricoarytenoid joint facet. Additionally, measurements of the circumferential arc of differently sized ET tubes were made alongside both cricoarytenoid joint capsules. This information was used to design a silastic stent that would function as a self-retaining interarytenoid spring to treat posterior glottic stenosis in 5 patients. Four of 5 patients included in the clinical study were tracheotomy dependent, primarily because of glottic stenosis. The human surgical technique is described in detail.

Results:

The shortest distance between the outer diameter of the ET tube to the medial cricoid facet averaged 5.02 mm in men and 3.62 mm in women. On the basis of the diameter of the intralaryngeal component of the initially round stent, and the position of the cricoarytenoid joint facets, the interarytenoid spring would have a subtended arc between 110° and 175°. These data helped fashion parameters for modifying a conventional T-tube to form a new self-retaining silastic interarytenoid spring. The first 5 human cases have been successful, allowing effective tracheotomy tube decannulation and excellent voice quality.

Conclusions:

The anatomic investigation herein provided key insights into ET tube–induced glottic stenosis and facilitated a new straightforward procedure to surgically improve the airway yet preserve excellent vocal function in patients with acquired glottic stenosis. Level of Evidence: NA

Hyperbranched poly(ethylenimine-co-oxazoline) by thiol–yne chemistry for non-viral gene delivery: investigating the role of polymer architecture

Synthesis of long-chain hyperbranched poly(ethylenimine-co-oxazoline)s by AB₂ thiol–yne chemistry is reported, and their application as pDNA transfection agents studied.

Branched poly (trimethylphosphonium ethylacrylate-co-PEGA) by RAFT: alternative to cationic polyammoniums for nucleic acid complexation

Cationic and highly branched poly (trimethylphosphonium ethylacrylate-co-poly (ethylene glycol) acrylate) (p (TMPEA-co-PEGA)), and its ammonium equivalent, have been synthesised from post-polymerisation modification of a poly (bromo ethylacrylate-co-poly (ethylene glycol) acrylate) (p (BEA-co-PEGA)) precursor polymer produced using reversible addition fragmentation chain transfer (RAFT) polymerisation. The cationic polymers were evaluated for their ability to complex nucleic acids, their in vitro cytotoxicity and their GFP pDNA transfection efficiency. The results show RAFT copolymerisation of BEA and PEGA is a simple route to polyphosphoniums showing reduced cytotoxicities and higher transfection efficiencies than their polyammonium alternatives.

Vocal Fold Motion Recovery in Patients With Iatrogenic Unilateral Immobility: Cervical Versus Thoracic Injury

Objectives:

Prognostic information about the return of vocal fold mobility in patients with iatrogenic unilateral vocal fold immobility (UVFI) can help with informed decisions about temporary and permanent treatment options. Although many variables can influence the likelihood of recovery, clinical experience suggests that cervical versus thoracic injury is a determining factor. The purpose of this study was to compare recovery rates from UVFI between cervical and thoracic injuries.

Methods:

A retrospective review of the medical record was performed on all adult patients diagnosed with complete iatrogenic UVFI from 2005 to 2015 (n = 923). Patients with incomplete data and etiologies of idiopathic, malignancy, or stenosis were excluded, leaving a study cohort of 502 patients who were categorized as having UVFI after cervical (n = 329) or thoracic (n = 173) injury. Data regarding site of iatrogenic injury (cervical vs thoracic), mobility status, and time interval to recovery or surgical intervention were recorded and compared using χ2 analyses.

Results:

Overall, 15% of patients recovered vocal fold mobility at a median of 4.1 months. Patients with cervical injury (65 of 329 [20%]) were significantly more likely to recover mobility than patients with thoracic injury (11 of 173 [6.4%]) (odds ratio, 3.63). The cervical cohort contained more women (68% vs 31%) and was younger (mean age, 60.4 ± 13.8 vs 64.1 ± 16.1 years; Cohen’s D = 0.25).

Conclusions:

Patients with cervical injuries resulting in UVFI are 4 times more likely to recover mobility than patients with thoracic injuries. This information can be valuable in counseling patients with UVFI and may affect clinical decision making.

Wound healing after transoral angiolytic laser surgery for early glottic carcinoma

OBJECTIVES/HYPOTHESIS

Wound healing after transoral angiolytic laser surgery for early glottic carcinoma was analyzed to identify factors influencing healing and clinical significance of persistent granulation tissue.

STUDY DESIGN

Retrospective review.

METHODS

A retrospective review of 100 consecutive patients undergoing endoscopic angiolytic laser surgery for T1 and T2 glottic carcinoma was performed. Patients with prior radiation or incomplete data were excluded. Postoperative endoscopic images were analyzed for time to healing, size and location of wound, and presence of granulation tissue. Three blinded, independent raters graded wound appearance and presence of granulation tissue.

RESULTS

Seventy-nine patients healed without need for intervention at a median of 3.5 months. Two patients had office-based ablation of granulation without biopsy and healed. The remaining 19 patients had biopsy for granulation tissue. Wounds that underwent biopsy at >3 months were more likely to contain carcinoma (5/6 patients, 83%) than wounds that were biopsied <3 months (2/13 patients, 15%) (P = .004). Presence of granulation significantly correlated with resection involving anterior commissure (P = .01), > 75%vocal fold length (P = .006), and depth into muscle (P = .001). Delayed healing (>3 months) correlated with T2b tumors (P = .02), depth into ligament (P = .002) and anterior commissure involvement (P = .04). T1a carcinomas more commonly healed in <3 months (P = .005).

CONCLUSIONS

Many vocal fold wounds heal completely within 3.5 months after angiolytic laser surgery for early glottic carcinoma. Larger and deeper wounds are more likely to heal with granulation tissue. Granulation can resolve without surgical intervention; however, granulation present > 3 months warrants biopsy due to increased risk of malignancy.

LEVEL OF EVIDENCE

4 Laryngoscope, 129:435-440, 2019.

Efficient Binding, Protection, and Self-Release of dsRNA in Soil by Linear and Star Cationic Polymers

Double stranded RNA (dsRNA) exhibits severe degradation within 3 days in live soil, limiting its potential application in crop protection. Herein we report the efficient binding, protection, and self-release of dsRNA in live soil through the usage of a cationic polymer. Soil stability assays show that linear poly(2-(dimethylamino)ethyl acrylate) can delay the degradation of dsRNA by up to 1 week while the star shaped analogue showed an increased stabilization of dsRNA by up to 3 weeks. Thus, the architecture of the polymer can significantly affect the lifetime of dsRNA in soil. In addition, the hydrolysis and dsRNA binding and release profiles of these polymers were carefully evaluated and discussed. Importantly, hydrolysis could occur independently of environmental conditions (e.g., different pH, different temperature) showing the potential for many opportunities in agrochemicals where protection and subsequent self-release of dsRNA in live soil is required.

A Comparison of Laser-Protected Endotracheal Tubes

OBJECTIVES

To compare the physical characteristics of 3 laser-protected endotracheal tubes (LPETs) commonly used in endoscopic laser surgery. To report potential intraoperative problems related to LPET use and suggest practical solutions.

STUDY DESIGN

Comparative analysis.

SETTING

Academic laboratory.

SUBJECTS AND METHODS

Physical characteristics of the Mallinckrodt Laser-Flex (MTL), Medtronic Laser-Shield II (ML-II), and Rusch LaserTubus (RL) were compared. The effect of bending LPETs on airflow resistance was estimated with a pressure transducer. The force required to pull each tube through the glottis and the pressure exerted during this maneuver were measured in a fresh cadaveric human larynx.

RESULTS

The design features and physical characteristics of LPETs differ, including varying balloon-tip lengths. Bending LPETs to acute angles caused significant pressure increase within the RL tube (Δ 3.42 cm H₂O) and minimal change within the ML-II (Δ 0.12 cm H₂O) and MTL (Δ 0.21 cm H₂O) tubes. The average force required to pull the RL (48.12 g, P = .003) and MTL (282.4 g, P = .001) tubes through the glottis was 7.6× and 44.5× greater than that for the ML-II (6.39 g). When pulled through the vocal folds, the ML-II cuff exerted no detectable pressure, whereas higher pressures were measured for the RL (2.2 cm H₂O) and MTL (6.5 cm H₂O) tubes.

CONCLUSION

The ML-II tube had the most favorable characteristics, with minimal pressure during extubation and resistance to kinking. The RL tube kinks readily with a resultant increase in resistance to airflow. The MTL tube extends farther into the trachea due to a relatively elongated balloon-tip configuration. Future LPET designs should incorporate features that avoid intraoperative difficulties related to airway protection and ventilation.

Cationic and hydrolysable branched polymers by RAFT for complexation and controlled release of dsRNA

The complexation and sustained release of dsRNA from highly branched polymers prepared via RAFT polymerisation and copolymerisation of the monomers DMAEA, DMAPA, and DMAEMA, is reported.

Self-Ratings of Vocal Status in Daily Life: Reliability and Validity for Patients With Vocal Hyperfunction and a Normative Group

PURPOSE

The aim of this study was to establish reliability and validity for self-ratings of vocal status obtained during the daily activities of patients with vocal hyperfunction (VH) and matched controls.

METHOD

Eight-four patients with VH and 74 participants with normal voices answered 3 vocal status questions-difficulty producing soft, high-pitched phonation (D-SHP); discomfort; and fatigue-on an ambulatory voice monitor at the beginning, 5-hr intervals, and the end of each day (7 total days). Two subsets of the patient group answered the questions during a 2nd week after voice therapy (29 patients) or laryngeal surgery (16 patients).

RESULTS

High reliability resulted for patients (Cronbach's α = .88) and controls (α = .95). Patients reported higher D-SHP, discomfort, and fatigue (Cohen's d = 1.62-1.92) compared with controls. Patients posttherapy and postsurgery reported significantly improved self-ratings of vocal status relative to their pretreatment ratings (d = 0.70-1.13). Within-subject changes in self-ratings greater than 20 points were considered clinically meaningful.

CONCLUSIONS

Ratings of D-SHP, discomfort, and fatigue have adequate reliability and validity for tracking vocal status throughout daily life in patients with VH and vocally healthy individuals. These questions could help investigate the relationship between vocal symptom variability and putative contributing factors (e.g., voice use/rest, emotions).

Integration of Motor Learning Principles Into Real-Time Ambulatory Voice Biofeedback and Example Implementation Via a Clinical Case Study With Vocal Fold Nodules

PURPOSE

Ambulatory voice biofeedback (AVB) has the potential to significantly improve voice therapy effectiveness by targeting one of the most challenging aspects of rehabilitation: carryover of desired behaviors outside of the therapy session. Although initial evidence indicates that AVB can alter vocal behavior in daily life, retention of the new behavior after biofeedback has not been demonstrated. Motor learning studies repeatedly have shown retention-related benefits when reducing feedback frequency or providing summary statistics. Therefore, novel AVB settings that are based on these concepts are developed and implemented.

METHOD

The underlying theoretical framework and resultant implementation of innovative AVB settings on a smartphone-based voice monitor are described. A clinical case study demonstrates the functionality of the new relative frequency feedback capabilities.

RESULTS

With new technical capabilities, 2 aspects of feedback are directly modifiable for AVB: relative frequency and summary feedback. Although reduced-frequency AVB was associated with improved carryover of a therapeutic vocal behavior (i.e., reduced vocal intensity) in a patient post-excision of vocal fold nodules, causation cannot be assumed.

CONCLUSIONS

Timing and frequency of AVB schedules can be manipulated to empirically assess generalization of motor learning principles to vocal behavior modification and test the clinical effectiveness of AVB with various feedback schedules.

Well-defined hyperstar copolymers based on a thiol–yne hyperbranched core and a poly(2-oxazoline) shell for biomedical applications

Well defined ‘hyperstar’ copolymers were synthesized by combining hyperbranched polymers produced by thiol–yne chemistry with poly(oxazoline)s.

Comparison of Videostroboscopy to Stroboscopy Derived From High-Speed Videoendoscopy for Evaluating Patients With Vocal Fold Mass Lesions

PURPOSE

Videostroboscopy (VS) uses an indirect physiological signal to predict the phase of the vocal fold vibratory cycle for sampling. Simulated stroboscopy (SS) extracts the phase of the glottal cycle directly from the changing glottal area in the high-speed videoendoscopy (HSV) image sequence. The purpose of this study is to determine the reliability of SS relative to VS for clinical assessment of vocal fold vibratory function in patients with mass lesions.

METHODS

VS and SS recordings were obtained from 28 patients with vocal fold mass lesions before and after phonomicrosurgery and 17 controls who were vocally healthy. Two clinicians rated clinically relevant vocal fold vibratory features using both imaging techniques, indicated their internal level of confidence in the accuracy of their ratings, and provided reasons for low or no confidence.

RESULTS

SS had fewer asynchronous image sequences than VS. Vibratory outcomes were able to be computed for more patients using SS. In addition, raters demonstrated better interrater reliability and reported equal or higher levels of confidence using SS than VS.

CONCLUSION

Stroboscopic techniques on the basis of extracting the phase directly from the HSV image sequence are more reliable than acoustic-based VS. Findings suggest that SS derived from high-speed videoendoscopy is a promising improvement over current VS systems.

Injectable Aorta Tissue Paste for Vocal Fold Medialization: Residence Time, Biocompatibility, and Comparison to Predicates in a Guinea Pig Subdermal Model

OBJECTIVES

Aortic homografts integrate well with laryngeal tissue when used in reconstructive surgery. It was hypothesized that a paste of aortic homograft, rich in slow-to-degrade elastin, would compare favorably in residence time and biocompatibility to predicate materials used for vocal fold injection-medialization.

METHODS

An injectable aorta paste (AP) was made by pulverizing aortic homografts at -196°C (cryomilling). To assess residence time and biocompatibility, 0.3 cc was injected subdermally in guinea pigs (n = 3 per 2-, 4-, 8-, 16-, 24-week time points) followed by histological analysis. To test particle size versus residence time, APs made using 80 or 200 seconds of cryomilling were compared. Implant characteristics of AP were then compared to Restylane, Radiesse Voice (Hydroxylapatite), Radiesse Voice Gel, and Cymetra in additional animals (n = 6 per 4-, 8-, 12-week time points).

RESULTS

Injected AP formed ovoid masses with minimal inflammation. Cellular infiltration was mild and increased with survival time. There was a gradual reduction of implant volume to ~40% at 24 weeks. Increased residence time for paste with larger particles (80 cryomilling seconds) was noted. Von Kossa staining showed progressive calcification of the AP. Cymetra was difficult to reconstitute reliably but formed subdermal masses similar to AP in shape, size, and reactivity and without calcification. The other predicates showed good biocompatibility but spread more widely and erratically in the tissue.

CONCLUSION

Aortic paste is easy to create, biocompatible, degrades slowly, and forms well-defined implants in guinea pig subdermal tissue. The AP implants calcified over time, and experiments are ongoing to determine the source of calcification and how it might be controlled or exploited clinically.

Chick Chorioallantoic Membrane as a Model for Simulating Human True Vocal Folds

Objectives:

Evolving photoangiolytic laser techniques for treating vocal fold lesions motivated the development of a model for research and surgical training. The chick chorioallantoic membrane (CAM), which is composed of a microvasculature suspended within the egg albumen, simulates the vocal fold microcirculation within the superficial lamina propria (SLP). To characterize this model, we compared measurements of vessel diameters to superficial vessels in human vocal folds.

Methods:

The diameters of first-, second-, and third-order CAM vessels were measured in fertilized chicken eggs. The superficial blood vessels of the human vocal fold were measured from intraoperative images.

Results:

According to the branching pattern, vessel segments were identified as first-, second-, or third-order, with average diameters of 0.035 mm (0.02 to 0.1 mm), 0.18 mm (0.12 to 0.41 mm), and 0.8 mm (0.6 to 0.98 mm), respectively. The total vessels measured included 362 first-order, 119 second-order, and 82 third-order vessels. In 10 adult human vocal folds, an average vessel diameter of 0.04 mm (0.015 to 0.1 mm) was observed in 50 vessels.

Conclusions:

The CAM microvasculature suspended in albumen provides a useful surgical model simulating the microcirculation within the SLP of the human vocal fold. Although first-order CAM vessels best approximate the size of normal vocal fold subepithelial vessels seen at surgery, second- and third-order vessels resemble the vascular abnormalities frequently encountered during microsurgery for phonotraumatic lesions.

Office-Based 532-nm Pulsed KTP Laser Treatment of Glottal Papillomatosis and Dysplasia

Objectives:

Treatment of glottal papillomatosis and dysplasia was mirror-guided and done in surgeons' offices in the 19th century. It migrated to the operating room in the 20th century to accommodate direct laryngoscopic surgery, which required assistants to administer anesthesia and procedural support. The primary treatment goals, which are disease regression and voice restoration and/or maintenance, are tempered by the morbidity of general anesthesia and potential treatment-induced vocal deterioration. To obviate general anesthesia, office-based laser laryngeal surgery was first done in 2001 with the 585-nm pulsed dye laser (PDL), because it employs a fiber delivery system and its energy is selectively absorbed by oxyhemoglobin. Since then, this new angiolytic laser treatment paradigm has become a mainstay of management for many surgeons; however, there are a number of shortcomings of the PDL. To further develop this concept and address the limitations of the PDL, we used a 532-nm pulsed potassium titanyl phosphate (KTP) laser.

Methods:

A prospective assessment was performed on 48 patients in 72 cases of recurrent glottal dysplasia (36) or papillomatosis (36). All individuals had previously undergone microlaryngoscopic management with histopathologic evaluation.

Results:

Two dysplasia patients did not tolerate the procedure. Of the treatable dysplasia cases, there was follow-up in 29 of 34. Disease regression was at least 75% in 18 of 29 cases (62%), 50% to 75% in 7 of 29 (24%), and 25% to 50% in the remaining 4 of 29 (14%). Papilloma patients returned for treatment when symptoms recurred, so disease regression could not be assessed accurately. Similar to data obtained with the PDL, these data confirmed that dysplastic mucosa could normalize without resection.

Conclusions:

Our observations revealed that the 532-nm pulsed KTP laser provided enhanced performance over the PDL laser in a number of ways. The ability to use smaller glass fibers precluded mechanical trauma to the channels of the flexible laryngoscopes and allowed for improved suctioning of secretions. Oxyhemoglobin absorbs energy better at 532 nm than at 585 nm, and the KTP laser can be delivered through a longer pulse width. These factors provide enhanced hemostasis and improved intralesional energy absorbance. Finally, unlike the PDL, the KTP laser is a solid-state laser and is not prone to mechanical failure.

Office-Based Treatment of Glottal Dysplasia and Papillomatosis with the 585-NM Pulsed Dye Laser and Local Anesthesia

Treatment of glottal papillomatosis and dysplasia was mirror-guided and performed in surgeons' offices in the 19th century. It migrated to the operating room in the 20th century to accommodate direct laryngoscopic surgery, which required assistants to administer anesthesia and procedural support. Presently, the primary treatment goals, which are disease regression and voice restoration or maintenance, are tempered by the morbidity of general anesthesia and potential treatment-induced vocal deterioration. In fact, general anesthesia has been appropriately considered to be an acceptable source of morbidity for the promise of a precise procedure, which usually ensures airway safety and an optimal vocal outcome. However, patients with recurrent glottal papillomatosis and keratosis with dysplasia are typically monitored with various degrees of watchful waiting until there is a subjective judgment (on the part of the patient and surgeon) that the disease is more of a liability than is the procedure to treat it. Innovations in the 585-nm pulsed dye laser delivery system have allowed for its use in the clinic with local anesthesia through the working channel of a flexible fiberoptic laryngoscope. A prospective assessment was done on 51 patients in 82 cases of recurrent glottal papillomatosis (30) and dysplasia (52). All individuals had previously undergone microlaryngoscopic management with histopathologic evaluation. Five procedures could not be completed because of impaired exposure (2) or discomfort (3). Of those patients who could be treated, there was at least a 50% disease involution in 68 of 77 cases (88%) and 25% to 50% disease regression in the remaining 9 (12%). Patient self-assessment of the voice revealed that 34 of 77 were improved, 39 were unchanged, 4 were slightly worse, and none were substantially worse. These data confirm that diseased mucosa can be normalized without resection or substantial loss of vocal function. The putative mechanisms, which vary according to the fluence (energy) delivered by the laser, are photoangiolysis of sublesional microcirculation, denaturing of epithelial basement membrane linking proteins, and cellular destruction. Furthermore, this relatively safe, effective technique allowed for treatment of many patients (in a clinic setting) in whom classic surgery-related morbidity would have often delayed intervention.

Office-Based and Microlaryngeal Applications of a Fiber-Based Thulium Laser

Objectives:

The carbon dioxide (CO2) laser is the premier dissecting instrument for hemostatic cutting and ablation during endolaryngeal surgery. However, microlaryngeal tangential dissection and office-based photoablation have been limited by the lack of a fiber-based delivery system. To address this limitation, a new laser was designed, which is a diode-pumped solid-state laser with a thulium-doped yttrium-aluminum-garnet laser rod. It produces a continuous-wave beam with a wavelength of 2,013 nm and a target chromophore of water. This new laser functions similarly to a CO2 laser with the benefit of being delivered through a small glass fiber (0.365 to 0.550 mm).

Methods:

A prospective pilot trial was done in 74 cases to explore applications of the new thulium laser. Thirty-two procedures were done with the laser used as an ablating instrument and topical anesthesia through a flexible laryngoscope (papillomatosis, 20; microinvasive carcinoma, 6; benign supraglottic lesions, 3; edema, 2; granuloma, 1). Forty-two procedures were done with the laser used as a cutting or ablating instrument for microlaryngeal dissection and general anesthesia. These included 27 partial laryngeal resections (supraglottis, 15; glottis, 10; subglottis, 2) and 8 posterior glottic laryngoplasties. The laser was also used as an ablative instrument during microlaryngoscopy in 7 cases.

Results:

The thulium laser was used effectively in all cases, under both local and general anesthesia. In microlaryngeal dissection, electrocautery was not needed to control bleeding, even during cutting in the highly vascular paraglottic space. No complications related to the use of the thulium laser were experienced in any case.

Conclusions:

Because of the fiber-based delivery system, the 2,013-nm continuous-wave thulium laser shows substantial promise for tangential dissection during microlaryngoscopy and soft tissue photoablation during office-based flexible laryngoscopy. Hemostasis was judged to be superior to experiences with the CO2 laser. In this pilot study, performing en bloc laryngeal cancer resection procedures was facilitated by use of the thulium laser.

Suspension Laryngoscopy Revisited

Every critical advancement in direct laryngoscopic surgical technique has enhanced its precision. Among the most notable was Killian's seminal description of suspension laryngoscopy 90 years ago, which allowed for bimanual direct laryngoscopic surgery. Because of the technical difficulties encountered while performing suspension laryngoscopy, Brünings and Seiffert designed fulcrum laryngoscope holder-stabilizers for spatula laryngoscopes from Killian's original instrument design. Their devices, which were easier to use and better tolerated by patients, were supported from the laryngeal cartilage framework or chest wall. Laryngoscope holder-stabilizers were retrofitted to tubular laryngoscope specula in the 1940s and 1950s, whereupon they became very popular. Suspension laryngoscopy should have become more common subsequent to the introduction of general endotracheal anesthesia with paralysis in the 1960s. However, laryngoscope holder-stabilizers were entrenched as the device preferred by most, and they remain so today. This entrenchment occurred despite the fact that suspension laryngoscopy allows for positioning a larger examining speculum, which in turn allows for enhanced exposure and endolaryngeal procedural precision. The applied vector forces on the mandible, maxilla, oral cavity, pharynx, and larynx associated with suspension laryngoscopy are preferable to those associated with holder-stabilizers. A prospective assessment of 120 cases revealed effective use of suspension laryngoscopy in all. We believe that only a minority of surgeons has actually seen true suspension laryngoscopy and that its merits are worthy of reexamination.

Bedside Injection Medialization Laryngoplasty in Immediate Postoperative Patients

Objectives

The morbidity of glottic insufficiency resulting from unilateral vocal fold immobility may significantly compromise postoperative recovery in patients with decreased pulmonary reserve or inability to protect their airway. Injection medialization laryngoplasty is an effective means of treating glottic insufficiency due to unilateral vocal fold immobility. The purpose of this study is to present our experience with bedside transoral injection medialization laryngoplasty in the immediate postoperative period.

Study Design

Case series with chart review.

Setting

Academic tertiary care hospital.

Subjects and Methods

Patient demographics, clinical characteristics, procedural details, and short-term outcome measures of oral intake were recorded in a cohort of 68 patients over 5 years with unilateral vocal cord paralysis who underwent injection medialization as a bedside procedure in the immediate postoperative period.

Results

Mean time to injection was 8.2 days postoperatively. At the time of injection, 40 of 68 patients were nil per os. Seventy percent (28 of 40) had their diet advanced to adequate oral intake within 5 days of injection. Greater than half of the injections (36 of 68) were performed in the intensive care unit. No complications were noted, and all patients in this cohort were able to tolerate the bedside injection.

Conclusion

Bedside injection medialization laryngoplasty in the immediate postoperative period via the transoral approach can be performed in patients, even in the intensive care unit, while on anticoagulation, and may be of benefit for hospitalized patients with unilateral vocal fold immobility. Further studies quantifying improvement in voice and swallowing data are merited.

Average Ambulatory Measures of Sound Pressure Level, Fundamental Frequency, and Vocal Dose Do Not Differ Between Adult Females With Phonotraumatic Lesions and Matched Control Subjects

OBJECTIVES

Clinical management of phonotraumatic vocal fold lesions (nodules, polyps) is based largely on assumptions that abnormalities in habitual levels of sound pressure level (SPL), fundamental frequency (f0), and/or amount of voice use play a major role in lesion development and chronic persistence. This study used ambulatory voice monitoring to evaluate if significant differences in voice use exist between patients with phonotraumatic lesions and normal matched controls.

METHODS

Subjects were 70 adult females: 35 with vocal fold nodules or polyps and 35 age-, sex-, and occupation-matched normal individuals. Weeklong summary statistics of voice use were computed from anterior neck surface acceleration recorded using a smartphone-based ambulatory voice monitor.

RESULTS

Paired t tests and Kolmogorov-Smirnov tests resulted in no statistically significant differences between patients and matched controls regarding average measures of SPL, f0, vocal dose measures, and voicing/voice rest periods. Paired t tests comparing f0 variability between the groups resulted in statistically significant differences with moderate effect sizes.

CONCLUSIONS

Individuals with phonotraumatic lesions did not exhibit differences in average ambulatory measures of vocal behavior when compared with matched controls. More refined characterizations of underlying phonatory mechanisms and other potentially contributing causes are warranted to better understand risk factors associated with phonotraumatic lesions.

Revision Transcervical Medialization Laryngoplasty for Unilateral Vocal Fold Paralysis

Objective

To identify patterns of failure following transcervical medialization laryngoplasty for unilateral vocal fold paralysis and describe indications and revision techniques for optimal vocal outcomes.

Study Design

Case series with chart review.

Setting

Tertiary care center.

Subjects and Methods

Thirty-nine consecutive patients between January 2005 and April 2014 undergoing transcervical revision of failed primary medialization laryngoplasty were identified. Demographics, etiology, stroboscopic assessment, and surgical techniques were recorded. Patient self-assessment using the Voice-Related Quality-of-Life (VRQOL) questionnaire and objective acoustic and aerodynamic assessments performed pre- and postoperatively were analyzed using t tests for paired comparisons.

Results

Thirty-nine patients underwent 48 transcervical revision surgeries. Median follow-up was 14.6 months from time of final revision surgery. Indications included anterior glottic incompetence (38/48, 79%), posterior glottic incompetence (20/48, 42%), glottic overclosure (8/48, 17%), and/or decreased phonatory pliability (12/48, 25%). A combination of findings was present in 21 (44%) surgeries. Revision techniques included either anterior augmentation, arytenopexy, and cricothyroid subluxation (alone or in combination) in 46 of 48 (96%) patients or partial implant removal alone in 2 patients. Seven patients (18%) required multiple revisions. A complete set of voice parameters was available for 22 patients, and statistically significant improvements included VRQOL scores, fundamental frequency in females, jitter, noise-to-harmonic ratio, and mean airflow rate.

Conclusion

Patterns of failure in patients with suboptimal phonatory function after transcervical medialization laryngoplasty included persistent glottic incompetence, glottic overclosure, and decreased vocal fold pliability. Revision transcervical medialization surgery, guided by individualized consideration of vocal fold position and surface pliability, can improve phonatory outcomes.

Cu(0)-mediated living radical polymerisation in dimethyl lactamide (DML); an unusual green solvent with limited environmental impact

The synthesis of poly-acrylates, methacrylates and styrene derivatives by SET-LRP is reported in a user and environmentally friendly “green” solvent, dimethyl lactamide (DML).

Vocal Fold Leukoplakia: Controversies in Evaluation and Treatment

Program Description:

This miniseminar comprehensively reviews evaluation and management of laryngeal leukoplakia. Although white vocal fold lesions are common, management remains challenging. Doing too little may allow precancerous lesions to progress, while doing too much may create unnecessary dysphonia. Within a framework balancing oncologic with functional outcomes, and using case-based presentations, this miniseminar highlights challenges, controversies, and emerging paradigms in laryngeal leukoplakia care. Perspectives from laryngology, head and neck oncology, and radiation oncology will discuss innovations such as narrow-band imaging, optical coherence tomography, potassium titanyl phosphate (KTP) and CO2 laser, chemotherapy, radiotherapy, and photodynamic therapy as they apply to current and future state-of-the-art management.

Educational Objectives:

(1) Understand the risk of progression of laryngeal leukoplakia to carcinoma and need to balance oncologic efficacy with functional outcomes in leukoplakia care. (2) Review current and emerging techniques for accurate diagnosis, staging, and surveillance of laryngeal leukoplakia. (3) Discuss treatment alternatives for laryngeal leukoplakia, emphasizing surgical techniques of KTP, CO2, and cold-instrument phonosurgery and including potential roles of radiotherapy, photodynamic therapy, and chemotherapy.

Simulation Model for Transcervical Laryngeal Injection Providing Real-time Feedback

Objective:

This study aimed to develop and evaluate a model for teaching transcervical laryngeal injections.

Methods:

A 3-dimensional printer was used to create a laryngotracheal framework based on de-identified computed tomography images of a human larynx. The arytenoid cartilages and intrinsic laryngeal musculature were created in silicone from clay casts and thermoplastic molds. The thyroarytenoid (TA) muscle was created with electrically conductive silicone using metallic filaments embedded in silicone. Wires connected TA muscles to an electrical circuit incorporating a cell phone and speaker. A needle electrode completed the circuit when inserted in the TA during simulated injection, providing real-time feedback of successful needle placement by producing an audible sound. Face validation by the senior authorconfirmed appropriate tactile feedback and anatomical realism. Otolaryngologists pilot tested the model and completed presimulation and postsimulation questionnaires.

Results:

The high-fidelity simulation model provided tactile and audio feedback during needle placement, simulating transcervical vocal fold injections. Otolaryngology residents demonstrated higher comfort levels with transcervical thyroarytenoid injection on postsimulation questionnaires.

Conclusion:

This is the first study to describe a simulator for developing transcervical vocal fold injection skills. The model provides real-time tactile and auditory feedback that aids in skill acquisition. Otolaryngologists reported increased confidence with transcervical injection after using the simulator.

Effect of Mandibular Tori on Glottic Exposure During Simulated Suspension Microlaryngoscopy

Objectives:

Mandibular tori have been identified as a contributing factor in difficult exposure during intubation. However, no investigation has measured the effect of mandibular tori on glottic exposure during suspension microlaryngoscopy (SML). The objective of this study was to measure how the size and location of mandibular tori affect glottic exposure during simulated SML at different thyromental distances.

Methods:

Suspension microlaryngoscopy was modeled on an anatomically accurate skull and larynx with thyromental distances between 6 and 12 cm. Mandibular tori were simulated by protruding screws 5 to 15 mm from the lingual aspect of the mandible. The tori were positioned either 15 mm (anterior) or 25 mm (posterior) from the midline of the symphysis. The glottic exposure for the various-size tori in each location was measured by recording the displacement of the glottiscope tip relative to the most anterior exposure achievable without tori. The glottiscope angle relative to the horizontal plane was measured for each condition.

Results:

Mandibular tori of more than 10 mm had a significant impact on glottic exposure. Displacement of the glottiscope tip ranged from 2 to 9 mm for anteriorly placed tori and from 7 to 29 mm for posteriorly placed tori, with larger tori causing greater displacement. Increasing the thyromental distance increased the posterior glottiscope tip displacement regardless of torus size or location. The glottiscope angle increased with larger tori (12º to 28º), but this angle did not change with increasing thyromental distance.

Conclusions:

Larger size and more-posterior location of mandibular tori more significantly reduce glottic exposure during SML. The inner table of the mandible is the most relevant anatomic constraint on glottic exposure, which varies with the presence or absence of mandibular tori independent of thyromental distance.

Absolut “copper catalyzation perfected”; robust living polymerization of NIPAM: Guinness is good for SET-LRP

The controlled polymerization of N-isopropyl acrylamide (NIPAM) is reported in a range of international beers, wine, ciders and spirits utilizing Cu(0)-mediated living radical polymerization (SET-LRP).

Surgical Innovations for Larynx and Pharynx Cancer

Program Description:

Transoral treatment of larynx and pharynx cancer has been done for over a century. Despite substantial technical innovations such as enhanced imaging, innovative laser technologies, and robotic guidance systems, chemoradiation protocols dominate treatment strategies at many institutions. Outcomes data on transoral microsurgical management for advanced oropharynx and larynx cancer will be presented to illustrate the efficacy of surgical management of these diseases. Robotics and laser photoangiolysis of laryngeal cancer are two emerging technologies that can enhance endoscopic surgery. This miniseminar will highlight advantages and disadvantages of endoscopic techniques and innovative technology through presentations from experts in the field.

Educational Objectives:

1) Evaluate outcomes data on transoral laser microsurgery for advanced oropharyngeal and laryngeal cancer. 2) Interpret the emerging role of robotics in the endoscopic surgical management of larynx and pharynx cancer. 3) Apply concepts of photoangiolysis in treatment of aerodigestive tract malignancy.

Voice outcomes for photoangiolytic KTP laser treatment of early glottic cancer

OBJECTIVES

Surgery and radiotherapy routinely provide high cure rates in treating early glottic cancer. Therefore, key metrics for success are optimal voice outcome and preservation of future cancer treatment options. Remarkably, there is a paucity of pretreatment versus posttreatment voice outcome data. Angiolytic KTP (potassium titanyl phosphate) laser treatment of early glottic cancer with ultranarrow margins was initiated to better preserve vocal function. Given that effective oncological results have been achieved, it was hypothesized that this approach would also result in improved posttreatment measures of vocal function that more closely approximate historical norms than pretreatment values.

METHODS

Pretreatment and posttreatment voice outcome data were obtained for 92 patients (64 with T1 cancer and 28 with T2 cancer) who underwent 532-nm KTP laser treatment of early glottic cancer in a study design in which each patient essentially served as his or her own control. The evaluations included objective measures (acoustic and aerodynamic) and patients' self-assessments of vocal function (Voice-Related Quality of Life; V-RQOL). A series of mixed analyses of variance were conducted for all vocal function measures, with tumor stage and depth of invasion as the between-subjects variables and time (presurgery versus postsurgery) as the within-subject variable.

RESULTS

There were statistically significant (p < or = 0.05) postoperative improvements for acoustic (perturbation and noise-to-harmonics ratio) and aerodynamic (subglottic pressure and vocal efficiency) measures of vocal function, as well as for V-RQOL assessment.

CONCLUSIONS

Comprehensive pretreatment and posttreatment voice measures in a large patient cohort demonstrated that the KTP laser significantly improved postoperative vocal function in patients with early glottic cancer. Furthermore, radiotherapy was preserved as an oncological treatment option.