Laryngology and phonosurgery

Management Experience of T1 Glottic Cancer Treated by CO2 Laser Surgery: A Cohort of 173 Patients

It was aimed to explore an alternative solution to manage T1 glottic cancer patients. One hundred seventy-three patients were enrolled. Seventy-eight cases were treated with type I and proved to be microinvasion cancer. Of them, 21 willingly selected followed up and 57 were further undergone type II. Ninety-five underwent type III and confirmed to be superficial invasion cancer in which Reinke's space was invaded. Five(23.8%), four(7.0%) and nine (9.5%)cases separately relapsed in type I, II and III. No significant difference was observed (p>0.05). 5/60, 5/11 and 8/102 patients respectively replaced in negative, positive and uncertain margin groups. There were remarkable differences among them (p<0.05). The recurrence rate is still low for patients with early glottic cancer undergone vocal cord resection using CO2 laser, and the appropriate surgical method should be selected for a diverse range of glottic cancer to avoid overtreatment. Patients with positive incisal margins have a relatively high recurrence rate and should take this situation seriously.

Blue light laser recontouring for pediatric benign fibrovascular vocal fold lesions

INTRODUCTION

Up to 40% of children with hoarseness due to benign fibrovascular vocal fold lesions do not respond to voice therapy and could benefit from further intervention to improve their communication abilities. Currently there are limited surgical options for children too young to comply with post-operative voice rest. We have begun using the 445 nm laser to recontour benign fibrovascular vocal fold lesions without post-operative voice rest in young children with hoarseness due to vocal fold nodules that is unresponsive to voice therapy. This report presents pilot data on the effect of this treatment on pediatric voice-related quality of life.

METHODS

Pediatric patients with benign fibrovascular lesions and severe subjective dysphonia (per parents or teachers) were given the option of undergoing surgery or continuing voice therapy. Those that opted for surgery underwent 445 nm laser recontouring of their vocal folds. They were discharged home the same day with no voice rest required. Pre- and post-demographic, acoustic measures, auditory perceptual assessments, and validated patient quality of life measures were collected.

RESULTS

Four patients (ages 3-8y, all male) were selected for surgery. The mean pre- and post-op PVRQOL scores were 59.4 (range: 22.5-80) and 98.1 (range: 97.5-100), respectively (low scores suggest lower voice-related QOL), and a mean change of 38.8 (previously established minimum clinically important difference: 12). Pre- and post-acoustic and aerodynamic measures similarly reflected this improvement.

CONCLUSION

This pilot case series addresses a commonly seen population (children with benign fibrovascular lesions and significant dysphonia despite voice therapy) where the best practice for timing and types of surgical intervention is unclear. Photoangiolytic lasers (including the 445 nm laser) are gaining popularity for the treatment of benign laryngeal pathologies, and their use may expand treatment possibilities for children with severe dysphonia due to benign vocal fold lesions that do not respond to voice therapy. Further longitudinal investigations are necessary to confirm the safety and efficacy.

Asiatic Acid Improves Extracellular Matrix Remodeling in Vocal Fold Scarring Via SMAD7 Activation

OBJECTIVES/HYPOTHESIS

Vocal fold (VF) fibroblasts are the central target for developing new strategies for the treatment of VF scarring and fibrosis. Asiatic acid (AA) is a triterpenoid derivate with antifibrotic properties. However, the effect of AA in VF scarring is poorly understood. The objective of this study was to investigate the potential application of AA as a therapeutic treatment in VF scarring.

STUDY DESIGN

Xxxxx.

METHODS

The functional expression of SMAD7 was knocked down with recombinant adenoviruses and adeno-associated viruses carrying shRNAs in the in vitro and in vivo models, which were constructed to investigate AA's antifibrotic function. The expression of collagens and SMADs in cultured human and rabbit cell lines and animal models was evaluated with quantitative reverse transcription polymerase chain reaction and immunohistochemistry labeling, respectively. Cell migration capacity and contraction in VF fibroblast cell lines were also evaluated.

RESULTS

AA downregulated the downstream fibrotic activation in a dose-dependent manner. Meanwhile, AA attenuated VF scarring/fibrosis by reducing collagen deposition. Furthermore, the antifibrotic effects of AA were associated with the upregulation of SMAD7. In contrast, knockdown of SMAD7 inhibited the effect of AA on transforming growth factor-beta-1 (TGF-β1) stimulation, which suggests a central role for SMAD7 in AA-induced antifibrotic activities during VF fibrosis.

CONCLUSION

We concluded that AA, which is a novel therapeutic candidate for preventing VF scarring/fibrosis, might exert its antifibrotic effect via the TGF-β1/SMAD signaling pathway.

LEVEL OF EVIDENCE

N/A Laryngoscope, 2021.

Bipedicled Vocal Fold Mucosal Flap: An Experimental Study

OBJECTIVE

To determine the dimensions of mucosal defects that can be covered by a bipedicled vocal fold mucosal flap.

METHODS

We used 20 adults human larynges (10 of each gender) excised from cadavers, divided into 2 groups of 10 larynges (5 of each gender) each. In one group (the normal flap group), we created the largest possible bipedicled vocal fold mucosal flap and then quantified the dimensions of the largest defect that could be covered by displacing the flap medially. In the other group (the augmented flap group), the flap was augmented laterally with mucosa from the laryngeal ventricle and we determined whether the larger flap would effectively cover larger defects.

RESULTS

The mean width of mucosal defect capable of being covered was 1.51 mm when the normal bipedicled flap was employed and was 1.67 mm when the augmented flap was applied. However, the difference was not statistically significant. We found that defect size correlated with vocal fold length, width and flap size in the normal flap group, whereas it correlated only with vocal fold length in the augmented flap group. The bipedicled flap is capable of covering larger defects in males.

CONCLUSION

Enlargement of a bipedicled vocal fold mucosal flap with laryngeal ventricular mucosa does not necessarily translate to an increase in the size of defect that can be covered. On average, the flap should be 30% larger than the width of the defect. The statistical model for predicting the defect size based on the vocal fold length, vocal fold width, and flap size has excellent predictive quality when a normal flap is employed.

Pathophysiology of Fibrosis in the Vocal Fold: Current Research, Future Treatment Strategies, and Obstacles to Restoring Vocal Fold Pliability

Communication by voice depends on symmetrical vibrations within the vocal folds (VFs) and is indispensable for various occupations. VF scarring is one of the main reasons for permanent dysphonia and results from injury to the unique layered structure of the VFs. The increased collagen and decreased hyaluronic acid within VF scars lead to a loss of pliability of the VFs and significantly decreases their capacity to vibrate. As there is currently no definitive treatment for VF scarring, regenerative medicine and tissue engineering have become increasingly important research areas within otolaryngology. Several recent reviews have described the problem of VF scarring and various possible solutions, including tissue engineered cells and tissues, biomaterial implants, stem cells, growth factors, anti-inflammatory cytokines antifibrotic agents. Despite considerable research progress, these technical advances have not been established as routine clinical procedures. This review focuses on emerging techniques for restoring VF pliability using various approaches. We discuss our studies on interactions among adipose-derived stem/stromal cells, antifibrotic agents, and VF fibroblasts using an in vitro model. We also identify some obstacles to advances in research.

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.

A Method for Reconstruction of Anterior Commissure Glottal Webs With Endoscopic Fibro-Mucosal Flaps

Background:

Anterior-commissure (AC) cicatrization and web formation is a difficult problem that can result from a variety of clinical scenarios. An advancement-rotation flap utilizing papillomatous epithelium and subepithelial fibrous tissue has been previously described. For patients in whom there was not excessive redundant papillomatosis covering the AC web, including other clinical scenarios, a microlaryngoscopic procedure was designed to lengthen the glottal/subglottal aperture using substantial local fibro-mucosal tissue. Although it has been done for over a decade, this approach is not widely known and to our knowledge not photo-documented.

Study Design:

Retrospective.

Material and Methods:

An analysis was done with Institutional Review Board approval that identified 42 patients who underwent 53 procedures to treat AC webs, which were reconstructed with local soft-tissue flaps and without any device/stent to maintain the glottal aperture. The microlaryngoscopic method and technical nuances for this approach with and without diseased epithelium are described and photo-documented. Tactical mucosal incisions were made to facilitate advancement and/or rotation of fibro-mucosal flaps with enough length to resurface the medial aspect of 1 vocal fold. The scarred submucosal soft tissue in the AC region was separated with cold instruments, and the flaps were sutured in position. Variations of this method are demonstrated mobilizing fibro-mucosal soft tissue from different locations, including the web itself, contralateral vocal fold, infrapetiole region, and/or the inner aspect of the thyroid lamina below the anterior-commissure tendon.

Results:

Of the 53 cases in which anterior commissure glottal webs were reconstructed with endoscopic fibro-mucosal flaps, 31 of 53 had recurrent respiratory papillomatosis (RRP). Redundant RRP comprised the majority of the flap in 14 of 31 RRP cases. Fibro-mucosal tissue without a substantial amount of disease occurred in 17 of 31 RRP cases. Of the remaining 22 AC web cases, the primary diagnoses observed were: glottic cancer = 7 of 22, intraepithelial dysplasia = 10 of 22, glottic trauma = 3 of 22, congenital = 1 of 22, and radiotherapy = 1 of 22.

Conclusion:

Endolaryngeal utilization of local fibro-mucosal tissue to lengthen the glottal/subglottal aperture for AC webs is an effective strategy. It can be done without using devices or keels for webs that are congenital or from nonsurgical trauma, idiopathic disease, or postsurgical traumatic cicatrization of the anterior commissure subsequent to treatment of epithelial disease (eg, cancer, dysplasia, and RRP). Normalizing the architecture of the anterior commissure was a valuable asset in patients who require future treatment of epithelial diseases, especially in an office-based setting.

Lubricin/proteoglycan 4 detected in vocal folds of humans and five other mammals

OBJECTIVES/HYPOTHESIS

Lubricin/proteoglycan-4 (PRG4) lubricates connective tissues such as joints and tendon sheaths, enabling them to better withstand shearing and frictional forces during motion. We wondered whether PRG4 might play a role in phonation, as normal vocal folds withstand repetitive, high-velocity deformations remarkably well. As a first step, we tested whether PRG4 is expressed in vocal folds.

STUDY DESIGN

Laboratory study.

METHODS

Anatomical and molecular methods were applied to 47 larynges from humans, macaque (Macaca fascicularis), canines, pigs, calves, and rats. Immunohistochemistry (IHC), Western blot, and quantitative real-time polymerase chain reaction (qRT-PCR) methods were used to test for the presence of PRG4.

RESULTS

In all species, the true vocal fold lamina propria (TVF-LP) was positive for PRG4 by IHC, whereas immunoreactivity of the false vocal fold was weak or absent, depending on the species. Human TVF-LP was strongly stained across all layers. Immunoreactivity was seen variably on the vocal fold surface and within the vocal fold epithelium, in the conus elasticus and thyroglottic ligament, and at the tip of vocal process. Western blots of four humans and six pigs demonstrated immunoreactivity at appropriate molecular weight. qRT-PCR of pig tissues confirmed PRG4 mRNA expression, which was highest in the TVF-LP.

CONCLUSIONS

PRG4 was found in phonatory tissues of six mammals. We suggest it might act as a lubricant within the lamina propria and possibly on the vocal fold surface, limiting phonation-related damage to vocal fold extracellular matrix and epithelium, and enhancing vocal efficiency by reducing internal friction (viscosity) within the vocal fold.

LEVEL OF EVIDENCE

NA Laryngoscope, 129:E229-E237, 2019.

Update on Management of Hoarseness

Dysphonia is altered voice quality, pitch, loudness, or vocal effort that impairs communication or decreases voice-related quality of life. Hoarseness is vocal roughness and a possible manifestation of dysphonia. This article uses the broader term dysphonia because it reflects of a wide range of voice complaints, with or without vocal roughness. Dysphonia is often caused by benign conditions but may also be the sentinel symptom of a serious or progressive condition requiring immediate diagnosis and management. The role of laryngeal visualization in assessment and diagnosis for these patients is critical.

The Ferret as a Surgical Model for Vocal Fold Scar Creation and Treatment

Objectives:

To develop a vocal fold (VF) scarring procedure in the ferret, characterize the scars histologically, and test the injectability of the lamina propria (LP). Secondarily, to compare laryngeal anatomy of the ferret with rat and rabbit.

Materials and Methods:

The larynges of 18 male ferrets were prepared by unilateral scarring, and normal larynges from 6 female Wistar rats and 5 male albino rabbits were used for comparative purposes. For scarring, the right VF were electrocauterized, ablating the entire LP. Prior to harvesting the larynges at 4 and 16 weeks, each ferret was re-anesthetized, and in 3 animals, India ink was injected into the LPs of both normal and scarred VFs.

Results:

Laryngoscopic methods and instrumentation for precise visualization, scarring, and injection were developed. The scarred VFs had reduced hyaluronic acid and increased collagen type I, III, and fibronectin compared with normal VFs. The 2 timepoints (4 and 16 weeks) differed significantly only in collagen type III level (levels were higher at 4 weeks). Injected ink migrated from scarred LP to muscle layer just beneath the scarred tissue 3 hours after injection.

Conclusion:

The ferret is a promising species for creation and experimental treatment of vocal fold scar.

Impact of Superparamagnetic Iron Oxide Nanoparticles on Vocal Fold Fibroblasts: Cell Behavior and Cellular Iron Kinetics

PURPOSE

The voice is the most important instrument of communication. Tissue defects in the vocal fold (VF) area lead to serious reduction in quality of life, but thus far, no satisfactory VF implant exists. Therefore, we aim to establish a functional VF implant in a rabbit model by magnetic tissue engineering (MTE) using superparamagnetic iron oxide nanoparticles (SPION). Hence, iron quantification over time as well as cell behavior studies upon SPION treatment are of great importance.

METHODS

Rabbit VF fibroblasts (VFF) were treated with different concentrations of SPIONs (20, 40, and 80 μg/cm²), and iron content was examined for up to 40 days using microwave plasma-atom emission spectroscopy. The effects of SPION treatment on VFF (adhesion, spreading, and migration), which are important for the formation of 3D structures, were tested.

RESULTS

Cellular SPION quantification revealed that there was no residual iron remaining in VFFs after 40 days. SPIONs had a dose-dependent effect on cell adhesion, with good tolerability observed up to 20 μg/cm². Migration and spreading were not significantly influenced by SPION treatment up to 80 μg/cm².

DISCUSSION AND CONCLUSION

To develop 3D structures, cell behavior should not be affected by SPION uptake. After 40 days, cells were free of iron as a result of metabolism or rarefication during cell division. Cell functions including adhesion, spreading, and migration were proven to be intact in a dose-dependent manner after SPION treatment, suggesting a safe usage of MTE for voice rehabilitation. Our results thus constitute a solid basis for a successful transfer of this technique into 3D constructs, in order to provide an individual and personalized human VF implant in the future.

Potential treatment for vocal fold scar with pirfenidone

OBJECTIVES/HYPOTHESIS

Pirfenidone (PFD) is a strong antifibrotic agent that has been clinically approved in Japan for idiopathic pulmonary fibrosis. We examined the antifibrotic effects of PFD on fibroblasts isolated from scarred vocal folds (VFs) of ferrets in vitro.

STUDY DESIGN

Prospective animal experiments with controls.

METHODS

Scar fibroblasts (SFs) were isolated from scarred VFs that had been electrocauterized 2 weeks before harvesting (N = 4). Normal fibroblasts (NFs) were isolated from intact VFs (N = 4). SFs and NFs were incubated in the presence of 10 ng/mL transforming growth factor β1 (TGF-β1), with or without PFD. After the 48-hour incubation, mRNA expression levels of α smooth muscle actin (αSMA), TGF-β1, collagen type I, and hyaluronan synthase 2 (HAS2) were examined by real-time polymerase chain reaction. Immunohistochemistry with anti-αSMA anti-collagen type I and phosphorylated Smad (p-Smad)2/3 antibodies in SFs with or without PFD was performed. SFs and NFs were cultured in collagen gel with or without PFD for 48 hours, and the extent of gel contraction was examined quantitatively.

RESULTS

PFD treatment significantly (P < .05) decreased mRNA expression of collagen type I, significantly increased mRNA expression of TGF-β1 and HAS2, and significantly suppressed collagen gel contraction. However, it did not have a significant effect on the expression of αSMA. The expression of p-Smad2/3 in the nucleus was faded with PFD, possibly demonstrating the suppression of translocation of p-Smad2/3 from cytoplasm to nucleus with PFD.

CONCLUSIONS

This is the first report to demonstrate the in vitro antifibrotic effects of PFD on fibroblasts isolated from scarred VFs of ferrets.

LEVEL OF EVIDENCE

NA. Laryngoscope, 128:E171-E177, 2018.

Laryngeal exposure and margin status in glottic cancer treated by transoral laser microsurgery

OBJECTIVE

Laryngeal exposure is one of the most limiting factors in transoral laser microsurgery (TLM) for glottic cancer. We evaluated the correlation between the degree of laryngeal exposure, as assessed by an easy previously described scoring tool (Laryngoscore), and histopathologic surgical margin status after TLM.

STUDY DESIGN

Prospective evaluation of 147 patients affected by Tis-T2 glottic cancer treated by TLM with curative intent between January 2012 and April 2016.

METHODS

All patients were preoperatively assessed and classified as having good (group A including Laryngoscore class 0-I) or suboptimal laryngeal exposure (group B including class II-III). Margins were classified as negative (more than 1 mm margin between healthy tissue and tumor) or positive (one/multiple superficial or deep margins involved by invasive or in situ carcinoma). Patients with multiple superficial or deep margin positivity were scheduled for TLM re-excision, open partial laryngectomy, or postoperative radiotherapy.

RESULTS

Twenty-one type I, 54 type II, 19 type III, 7 type IV, 41 type V, and 5 type VI cordectomies (according to the European Laryngological Society classification) were performed with an en-bloc or multi-bloc technique according to the size, site, and exposure of the lesion. Group A included 109 (74%) and group B included 38 (26%) patients. Positive surgical margins were overall observed in 39 (26.5%) cases: 21 (19.2%) in group A versus 18 (47.4%) in group B (P = 0.001).

CONCLUSION

Laryngeal exposure is one of the most important factors influencing TLM resection of glottic cancer within safe surgical margins. The importance of its adequate preoperative assessment cannot be overemphasized.

LEVEL OF EVIDENCE

2b. Laryngoscope, 128:1146-1151, 2018.

Robotic microlaryngeal phonosurgery: Testing of a "steady-hand" microsurgery platform

OBJECTIVES/HYPOTHESIS

To evaluate gains in microlaryngeal precision achieved by using a novel robotic "steady hand" microsurgery platform in performing simulated phonosurgical tasks.

STUDY DESIGN

Crossover comparative study of surgical performance and descriptive analysis of surgeon feedback.

METHODS

A novel robotic ear, nose, and throat microsurgery system (REMS) was tested in simulated phonosurgery. Participants navigated a 0.4-mm-wide microlaryngeal needle through spirals of varying widths, both with and without robotic assistance. Fail time (time the needle contacted spiral edges) was measured, and statistical comparison was performed. Participants were surveyed to provide subjective feedback on the REMS.

RESULTS

Nine participants performed the task at three spiral widths, yielding 27 paired testing conditions. In 24 of 27 conditions, robot-assisted performance was better than unassisted; five trials were errorless, all achieved with the robot. Paired analysis of all conditions revealed fail time of 0.769 ± 0.568 seconds manually, improving to 0.284 ± 0.584 seconds with the robot (P = .003). Analysis of individual spiral sizes showed statistically better performance with the REMS at spiral widths of 2 mm (0.156 ± 0.226 seconds vs. 0.549 ± 0.545 seconds, P = .019) and 1.5 mm (0.075 ± 0.099 seconds vs. 0.890 ± 0.518 seconds, P = .002). At 1.2 mm, all nine participants together showed similar performance with and without robotic assistance (0.621 ± 0.923 seconds vs. 0.868 ± 0.634 seconds, P = .52), though subgroup analysis of five surgeons most familiar with microlaryngoscopy showed statistically better performance with the robot (0.204 ± 0.164 seconds vs. 0.664 ± 0.354 seconds, P = .036).

CONCLUSIONS

The REMS is a novel platform with potential applications in microlaryngeal phonosurgery. Further feasibility studies and preclinical testing should be pursued as a bridge to eventual clinical use.

LEVEL OF EVIDENCE

NA. Laryngoscope, 128:126-132, 2018.

Practice variations in voice treatment selection following vocal fold mucosal resection

OBJECTIVES/HYPOTHESIS

To characterize initial voice treatment selection following vocal fold mucosal resection in a Medicare population.

STUDY DESIGN

Retrospective analysis of a large, nationally representative Medicare claims database.

METHODS

Patients with > 12 months of continuous Medicare coverage who underwent a leukoplakia- or cancer-related vocal fold mucosal resection (index) procedure during calendar years 2004 to 2009 were studied. The primary outcome of interest was receipt of initial voice treatment (thyroplasty, vocal fold injection, or speech therapy) following the index procedure. We evaluated the cumulative incidence of each postindex treatment type, treating the other treatment types as competing risks, and further evaluated postindex treatment utilization using the proportional hazards model for the subdistribution of a competing risk. Patient age, sex, and Medicaid eligibility were used as predictors.

RESULTS

A total of 2,041 patients underwent 2,427 index procedures during the study period. In 14% of cases, an initial voice treatment event was identified. Women were significantly less likely to receive surgical or behavioral treatment compared to men. From age 65 to 75 years, the likelihood of undergoing surgical treatment increased significantly with each 5-year age increase; after age 75 years, the likelihood of undergoing either surgical or behavioral treatment decreased significantly every 5 years. Patients with low socioeconomic status were significantly less likely to undergo speech therapy.

CONCLUSION

The majority of Medicare patients do not undergo voice treatment following vocal fold mucosal resection. Further, the treatments analyzed here appear disproportionally utilized based on patient sex, age, and socioeconomic status. Additional research is needed to determine whether these observations reflect clinically explainable differences or disparities in care.

LEVEL OF EVIDENCE

2c. Laryngoscope, 126:2505-2512, 2016.

Quantitative differentiation of normal and scarred tissues using second-harmonic generation microscopy

The aim of this study was to differentiate normal and scarred hamster cheek pouch samples by applying a quantitative image analysis technique for determining collagen fiber direction and density in second-harmonic generation microscopy images. This paper presents a collagen tissue analysis of scarred cheek pouches of four adult male Golden Syrian hamsters as an animal model for vocal fold scarring. One cheek pouch was scarred using an electrocautery unit and the other cheek was used as a control for each hamster. A home-built upright microscope and a compact ultrafast fiber laser were used to acquire depth resolved epi-collected second-harmonic generation images of collagen fibers. To quantify the average fiber direction and fiber density in each image, we applied two-dimensional Fourier analysis and intensity thresholding at five different locations for each control and scarred tissue sample, respectively. The resultant depth-resolved average fiber direction variance for scarred hamster cheek pouches (0.61 ± 0.03) was significantly lower (p < 0.05) than control tissue (0.73 ± 0.04), indicating increased fiber alignment within the scar. Depth-resolved average voxel density measurements indicated scarred tissues contained greater (p < 0.005) fiber density (0.72 ± 0.09) compared to controls (0.18 ± 0.03). In the present study, image analysis of both fiber alignment and density from depth-resolved second-harmonic generation images in epi-detection mode enabled the quantification of the increased collagen fiber deposition and alignment typically observed in fibrosis. The epi-detection geometry is the only viable method for in vivo imaging as well as imaging thick turbid tissues. These quantitative endpoints, clearly differentiating between control and scarred hamster cheek pouches, provide an objective means to characterize the extent of vocal fold scarring in vivo in preclinical and clinical research. In particular, this non-invasive method offers advantages for monitoring scar treatments in live animals and following the effects of scarring-related treatments such as application of steroids or drugs targeting pathways involved in fibrosis. SCANNING 38:684-693, 2016. © 2016 Wiley Periodicals, Inc.

Bioengineered vocal fold mucosa for voice restoration

Patients with voice impairment caused by advanced vocal fold (VF) fibrosis or tissue loss have few treatment options. A transplantable, bioengineered VF mucosa would address the individual and societal costs of voice-related communication loss. Such a tissue must be biomechanically capable of aerodynamic-to-acoustic energy transfer and high-frequency vibration and physiologically capable of maintaining a barrier against the airway lumen. We isolated primary human VF fibroblasts and epithelial cells and cocultured them under organotypic conditions. The resulting engineered mucosae showed morphologic features of native tissue, proteome-level evidence of mucosal morphogenesis and emerging extracellular matrix complexity, and rudimentary barrier function in vitro. When grafted into canine larynges ex vivo, the mucosae generated vibratory behavior and acoustic output that were indistinguishable from those of native VF tissue. When grafted into humanized mice in vivo, the mucosae survived and were well tolerated by the human adaptive immune system. This tissue engineering approach has the potential to restore voice function in patients with otherwise untreatable VF mucosal disease.

Pulsed Angiolytic Laser Treatment of Ectasias and Varices in Singers

Objectives:

Varices and ectasias in singers are typically the result of phonotraumatic shearing stresses and/or collision forces on the microcirculation within the superficial lamina propria. These lesions can be debilitating in performing vocalists because of the effect of recurrent hemorrhage and/or as a contributing factor to the morbidity of other mass lesions such as polyps, nodules, and cysts. Phonomicrosurgical treatment of performers is understandably approached with great trepidation, as the vocal liability of surgically disturbing the superficial lamina propria and epithelium must be balanced with the inherent detrimental vocal effect(s) of the lesion(s). Pulsed angiolytic lasers that emit radiation at high absorbance peaks of oxyhemoglobin were examined to determine whether they were an efficacious treatment approach for ectasias and varices based on these lasers' mechanisms of action and prior experience in phonomicrosurgery.

Methods:

A prospective trial was done in 39 patients (40 procedures in 54 vocal folds) without complication to evaluate the effectiveness of a 585-nm pulsed dye laser (PDL; 25 cases) and a 532-nm pulsed KTP laser (15 cases) in a noncontact mode to treat 65 varices and 43 ectasias. Twenty-nine of 39 patients had varices and ectasias associated with other phonotraumatic mass lesions that required resection.

Results:

All patients have resumed full vocal activities, and no patient has had a subsequent hemorrhage or vocal deterioration.

Conclusions:

Both the 585-nm PDL and the 532-nm pulsed KTP laser were found to be efficacious and relatively safe treatment modalities for vascular abnormalities of the vocal folds in singers. Noncontact selective photoangiolysis of the aberrant vessels prevented future bleeding without substantial photothermal trauma to the overlying epithelium and surrounding delicate superficial lamina propria, thereby allowing for optimal postoperative mucosal pliability and glottal sound production. However, the pulsed KTP laser was substantially easier to use because of its enhanced hemostasis due to its longer pulse width. Vessel wall rupture was commonplace during use of the 585-nm PDL, but rarely occurred during photoangiolysis with the 532-nm pulsed KTP laser.

A grading scale for pediatric vocal fold nodules

Objective

To design a grading scale for vocal fold nodules in pediatric patients.

Study Design and Setting

We conducted a prospective study in which a grading scale for vocal nodule size and contour based on static fiberoptic images of pediatric larynges was developed to achieve the scale presented here.

Results

Twenty-eight health care professionals each rated 28 images of pediatric vocal fold nodules. The intraclass correlation for nodule size was strong (0.77; 95% confidence interval, 0.67–0.87). The κ statistic for nodule contour was mild (0.35; 95% confidence interval, 0.33–0.37). Agreement between experienced and other raters found no significant difference for the nodule size or contour grade of a given image.

Conclusions

A grading scale for pediatric vocal fold nodules is presented. Interrater reliability for nodule size is high and can be reliably used by health care professionals with varying levels of experience.

Significance

A validated grading scale facilitates objective analysis of outcomes when studying and following patients with vocal nodules.

"Finding a Voice": Imaging Features after Phonosurgical Procedures for Vocal Fold Paralysis

Altered communication (hoarseness, dysphonia, and breathy voice) that can result from vocal fold paralysis, secondary to numerous etiologies, may be amenable to surgical restoration. In this article, both traditional and cutting-edge phonosurgical procedures targeting the symptoms resulting from vocal fold paralysis are reviewed, with emphasis on the characteristic imaging appearances of various injectable materials, implants, and augmentation procedures used in the treatment of vocal fold paralysis. In addition, complications of injection laryngoplasty and medialization laryngoplasty are illustrated. Familiarity with the expected imaging changes following treatment of vocal fold paralysis may prevent the misinterpretation of posttreatment changes as pathology. Identifying common complications related to injection laryngoplasty and localization of displaced implants is crucial in determining specific management in patients who have undergone phonosurgical procedures for the management of vocal fold paralysis.

Long-term Voice Outcomes of Early Thyroplasty for Unilateral Vocal Fold Paralysis Following Aortic Arch Surgery

Objective:

To describe this institution’s experience with and the long-term outcomes of early type 1 thyroplasty for unilateral vocal fold paralysis (UVFP) following surgery on the aortic arch.

Study Design:

Retrospective chart review with telephone questionnaire.

Setting:

Academic tertiary care center.

Subjects and Methods:

Three hundred forty-eight patients with UVFP following surgery on the aortic arch since 1999 were identified; 40 were available for follow-up. The number of revision procedures following initial thyroplasty was ascertained, and the Voice Handicap Index (VHI) was administered by telephone. The hypothesis that early thyroplasty produced voice outcomes and revision rates comparable to injection laryngoplasty was established prior to the initiation of data collection.

Results:

Six out of the 40 patients (15%) required revision thyroplasty following their initial procedure. Mean VHI of all patients was 36.0 (SD, 27.2). Mean VHI was significantly different in the 18 to 39 age group (13.1) when compared to the 40 to 59 (51.8) and 60+ (37.7) age groups ( P = .013). Mean follow-up since initial thyroplasty was 46.5 months (SD, 42.2).

Conclusions:

In the setting of aortic arch surgery with injury to the recurrent laryngeal nerve, early thyroplasty produces voice outcomes comparable to those achieved in the literature with repeated injection and delayed thyroplasty and can be considered in select populations.

Office removal of a subglottic bread clip

Objective. The presence of an upper airway foreign body is an emergent, potentially life-threatening situation that requires careful but rapid evaluation and management. Organic or nonorganic material may typically be found in the pyriform sinuses or tongue base or may be aspirated directly into the tracheobronchial tree. We present here an unusual case report of a patient who accidentally ingested a plastic bread clip that was lodged in his subglottis for 15 months and report successful removal in the office under local anesthesia. Methods. Mucosal anesthesia was achieved with inhaled 4% lidocaine spray. Flexible laryngoscopic removal of the foreign body was then successfully accomplished. Results. The patient's symptoms resolved completely following removal, with no sequelae. Conclusions. Office removal of airway foreign bodies is feasible and can be safely done with adequate topical anesthesia, but great caution and emergency planning must be exercised.

Diagnostic and therapeutic pitfalls in benign vocal fold diseases

More than half of patients presenting with hoarseness show benign vocal fold changes. The clinician should be familiar with the anatomy, physiology and functional aspects of voice disorders and also the modern diagnostic and therapeutic possibilities in order to ensure an optimal and patient specific management. This review article focuses on the diagnostic and therapeutic limitations and difficulties of treatment of benign vocal fold tumors, the management and prevention of scarred vocal folds and the issue of unilateral vocal fold paresis.

Persistent dysphonia after laryngomicrosurgery for benign vocal fold disease

Objectives

Laryngomicrosurgery (LMS) is used to manage most vocal fold lesions. However, the functional voice outcome of the LMS might be diverse due to the influence of various factors. We intend to evaluate the incidence and etiologic factors of persistent dysphonia after LMS for benign vocal fold disease (BVFD).

Methods

We performed a retrospective review of 755 patients who underwent LMS for BVFD. We analyzed the clinical characteristics, preoperative and postoperative two onths voice studies. Postsurgical dysphonia was defined as grade 1 or above in GRBAS (grade, roughness, breathiness, asthenia, and strain) scale. Thirty nine patients (5.2%; 25 males and 14 females; average, 42.9 years; range, 21 to 70 years) were diagnosed with postsurgical dysphonia.

Results

There was no correlation between the diagnosis, coexistence with laryngopharyngeal reflux disease, habit of smoking, or occupational voice abuse and voice outcome. The patients with a worse preoperative acoustic parameter had aworse voice outcome. Stroboscopic findings showed excessive scarring or bowing in 21 cases, presence of lesion remnant in eight cases, prolonged laryngeal edema in five and no abnormal findings in three.

Conclusion

Great care should be taken in patients with worse preoperative jitter. With a few exceptions, postoperative dysphonia can be avoided by the use of an ppropriate surgical technique.

Adult recurrent respirator papillomatosis: a new therapeutic approach with pegylated interferon alpha 2a (Peg-IFNα-2a) and GM-CSF

OBJECTIVE

To determine a new therapeutic approach using granulocyte monocyte-colony-stimulating factor (GM-CSF) and pegylated interferon alpha 2a (Peg-IFNα-2a) as adjuvant therapy in patients with adult recurrent respiratory papillomatosis.

STUDY DESIGN

Descriptive observational clinical trial.

SETTING

Departments of Otolaryngology and Immunology.

METHODS

Fourteen patients with adult recurrent respiratory papillomatosis were examined regarding medical history and number of operations before and after treatment. Voice disorder and glottal stop were evaluated using the Voice-Related Quality-of-Life instrument. Papilloma staging was determined using the Coltera/Derkay diagram. The patients received Peg-IFNα-2a at 180 mcg weekly for 6 months. In the third month, the patients began GM-CSF treatment at 400 mcg weekly for 2 months. The patients were observed for 12 months after treatment ended.

RESULTS

Eleven patients met the study criteria; 3 patients had tracheotomies before treatment, and they were decannulated after treatment. Before treatment, the scale of voice quality ranged from 34 to 45 points (mean, 38.31). After treatment, the range was 12 to 35 points (mean, 21.09; P < .001). Prior to therapy, the glottal stop ranged from 50% to 90% (average, 62.27%). After therapy, the range decreased to 0% to 15% (mean, 4.63%; P < .001). The number of surgical interventions decreased. Two patients each had 1 surgical intervention after treatment began.

CONCLUSION

A new adjuvant treatment based on immunogenetic mechanisms against human laryngeal papilloma virus, with expectations of reducing disease aggressiveness and the number of operations, avoids the risks of surgery.

IMPLICATION FOR PRACTICE

Peg-IFNα-2a and GM-CSF is an adjuvant therapy for treating adult recurrent respiratory papillomatosis.

Aortic Homograft Reconstruction of Partial Laryngectomy Defects: A New Technique

Objectives:

Wide-field transcervical partial laryngectomy often precludes tracheotomy decannulation. It is done infrequently today, primarily because of the popularity of chemotherapy-radiotherapy treatment regimens and limited enthusiasm for using transcervical partial laryngectomy after failed radiotherapy. We sought to identify a new reconstructive technique that would provide an alternative to total laryngectomy in as many patients as possible.

Methods:

We performed a retrospective examination of 15 patients who underwent single-stage wide-field transcervical partial laryngectomy with cryopreserved aortic homograft reconstruction. Eight of the 15 patients had previously undergone failed radiotherapy. At least 40% of the cricoid circumference was resected in 8 patients.

Results:

All 15 patients had their tracheotomy tube removed and have laryngeal phonation, and 14 of the 15 resumed oral intake. There were no major surgical complications.

Conclusions:

Use of aortic homografts is a new, reliable, and versatile reconstructive option for performing conservation laryngeal cancer surgery that allows for airway, swallowing, and voice preservation.

Towards endoscopic ultrafast laser microsurgery of vocal folds

Vocal fold scarring is a predominant cause of voice disorders yet lacks a reliable treatment method. The injection of soft biomaterials to improve mechanical compliance of the vocal folds has emerged as a promising treatment. Here, we study the use of precise femtosecond laser microsurgery to ablate subsurface voids, with a goal of eventually creating a plane in dense subepithelial scar tissue into which biomaterials can be injected for their improved localization. Specifically, we demonstrate the ablation of small subepithelial voids in porcine vocal fold tissue up to 120 [micro sign]m below the surface such that larger voids in the active area of vocal fold mucosa (~3×10 mm(2)) can eventually be ablated in about 3 min. We use sub-μJ, 776-nm pulses from a compact femtosecond fiber laser system operating at a 500-kHz repetition rate. The use of relatively high repetition rates, with a small number of overlapping pulses, is critical to achieving ablation in a very short time while still avoiding significant heat deposition. Additionally, we use the same laser for nonlinear optical imaging to provide visual feedback of tissue structure and to confirm successful ablation. The ablation parameters, including pulse duration, pulse energy, spot size, and scanning speed, are comparable to the specifications in our recently developed miniaturized femtosecond laser surgery probes, illustrating the feasibility of developing an ultrafast laser surgical instrument.

Assessment of canine vocal fold function after injection of a new biomaterial designed to treat phonatory mucosal scarring

OBJECTIVES

Most cases of irresolvable hoarseness are due to deficiencies in the pliability and volume of the superficial lamina propria of the phonatory mucosa. By using a US Food and Drug Administration-approved polymer, polyethylene glycol (PEG), we created a novel hydrogel (PEG30) and investigated its effects on multiple vocal fold structural and functional parameters.

METHODS

We injected PEG30 unilaterally into 16 normal canine vocal folds with survival times of 1 to 4 months. High-speed videos of vocal fold vibration, induced by intratracheal airflow, and phonation threshold pressures were recorded at 4 time points per subject. Three-dimensional reconstruction analysis of 11.7 T magnetic resonance images and histologic analysis identified 3 cases wherein PEG30 injections were the most superficial, so as to maximally impact vibratory function. These cases were subjected to in-depth analyses.

RESULTS

High-speed video analysis of the 3 selected cases showed minimal to no reduction in the maximum vibratory amplitudes of vocal folds injected with PEG30 compared to the non-injected, contralateral vocal fold. All PEG30-injected vocal folds displayed mucosal wave activity with low average phonation threshold pressures. No significant inflammation was observed on microlaryngoscopic examination. Magnetic resonance imaging and histologic analyses revealed time-dependent resorption of the PEG30 hydrogel by phagocytosis with minimal tissue reaction or fibrosis.

CONCLUSIONS

The PEG30 hydrogel is a promising biocompatible candidate biomaterial to restore form and function to deficient phonatory mucosa, while not mechanically impeding residual endogenous superficial lamina propria.

Hypopharyngeal extrusion of 2.5 feet (76 cm) of polytetrafluoroethylene (Gore-Tex): initial laser-assisted office-based removal and micropharyngeal completion

Extrusion of an implant after medialization laryngoplasty is unusual and warrants removal. Most commonly, it extrudes through the laryngeal introitus, but rarely, it extrudes through the pyriform sinus. A case report in which 2.5 feet (76 cm) of polytetrafluoroethylene (Gore-Tex) was removed from an 80-year-old female patient is presented to evaluate factors that led to this surgical complication and strategies that solved the problem. Because of the patient's multiple medical problems, initial removal of the foreign body was attempted in the office with topical anesthesia. When the Gore-Tex was noted to be lodged in the laryngeal parenchyma, it was severed at the edge of the pyriform sinus to stabilize the airway. Subsequently, microlaryngoscopic-controlled completion removal was done in the operating room with general anesthesia. The patient healed uneventfully with no further sequelae. Analysis of this case illustrates a number of factors leading to a rare iatrogenic foreign body complication. Office-based removal of the Gore-Tex implant evolved into a unique scenario in which the rapid use of a fiber-based laser to divide the foreign body facilitated stabilizing the airway to allow for elective completion removal in a controlled fashion.

Injectable hyaluronic acid-dextran hydrogels and effects of implantation in ferret vocal fold

Injectable hydrogels may potentially be used for augmentation/regeneration of the lamina propria of vocal fold tissue. In this study, hyaluronic acid (HA) and dextran were chemically modified and subsequently crosslinked via formation of hydrazone bonds in phosphate buffer. Swelling ratios, degradation, and compressive moduli of the resulting hydrogels were investigated. It was found that the properties of HA-dextran hydrogels were variable and the trend of variation could be correlated with the hydrogel composition. The biocompatibility of three injectable HA-dextran hydrogels with different crosslinking density was assessed in the vocal fold region using a ferret model. It was found that HA-dextran hydrogels implanted for three weeks stimulated mild foreign-body reactions. Distinct tissue-material interactions were also observed for hydrogels made from different formulations: the hydrogel with the lowest crosslinking density was completely degraded in vivo; while material residues were visible for other types of hydrogel injections, with or without cell penetration into the implantation depending on the hydrogel composition. The in vivo results suggest that the HA-dextran hydrogel matrices can be further developed for applications of vocal fold tissue restoration.

Voice rest versus exercise: a review of the literature

Voice rest is commonly prescribed after vocal fold surgery to promote wound healing of the vocal fold. Currently, there is no standard protocol that is established based on biological evidence. In orthopedic rehabilitation, long-term rest is found to be less effective for connective tissue healing than exercise. Connective tissue healing is also an important factor for successful voice rehabilitation; however, whether this concept can be extrapolated to voice rehabilitation is unknown. The purpose of this article is to review current clinical and basic science literature to examine the effect of voice rest in postsurgical rehabilitation. First, we present a summary of clinical literature that pertains to voice rest. Second, we present description of connective tissues that are involved in orthopedic and voice rehabilitation, specifically, ligament and lamina propria, respectively, and their wound healing process. Third, a summary of the literature from orthopedic research on the effect of rest versus exercise is presented. Lastly, it summarizes in vitro and in vivo studies that examined the effect of mechanical stress on vocal fold tissue. Current literature suggests that there is a lack of clinical evidence that supports a specific type and duration of voice rest, and extrapolation of the findings from orthopedic research may be unreasonable due to the morphological and biochemical difference between the tissues. To determine the effect of voice rest, further elucidation of vocal fold wound healing process and the effect of mechanical stress on vocal fold tissue remodeling are needed.

Use of lasers in laryngeal surgery

Lasers are a relatively recent addition to laryngeal surgery. Since their invention, laser use and applications have expanded rapidly. In this article, we discuss the benefits and disadvantages of lasers for different procedures, as well as ways to overcome commonly faced clinical problems. The use of lasers in surgery has offered a time- and cost-efficient alternative to cold surgical techniques, and has been used in the treatment of numerous laryngeal pathologies, including stenoses, recurrent respiratory papillomatosis, leukoplakia, nodules, malignant laryngeal disease, and polypoid degeneration (Reinke's edema). However, lasers can incur adjacent tissue damage and vocal fold scarring. These problems can be minimized through understanding the mechanisms by which lasers function and correctly manipulating the parameters under a surgeon's control. By varying fluence, power density, and pulsation, tissue damage can be decreased and lasers can be used with greater confidence. The various types of lasers and their applications to the treatment of specific pathologies are reviewed with the intention of helping surgeons select the best tool for a given procedure. Recent applications of lasers to treat benign laryngeal lesions and severe laryngomalacia demonstrate that additional research must be conducted to realize the full potential of this surgical tool.

Initial Anatomic Geographic Presentation of Glottal Dysplasia

Glottal dysplasia is likely the most common laryngeal disease with a discernible lesion; however, investigations describing its initial anatomic geographic presentation are rare. To examine this, we identified 52 patients who did not have significant prior treatment or glottal cancer. Thirty-one patients had bilateral disease, so there were 83 vocal folds with precancerous dysplasia. The phonatory mucosa was the dominant disease site in all; the epicenter was on the superior surface in 65 of the 83 folds and on the medial surface in 18 of the 83 folds. The arytenoid mucosa was involved in 8 of the 83 folds. Nineteen of the 52 patients had direct anterior-commissure involvement, and none had interarytenoid mucosal disease. The investigation established the commonly held principle that glottal dysplasia occurs primarily on phonatory mucosa. Given the frequent occurrence and recurrence of glottal dysplasia, treatment goals should focus on disease control to prevent malignant degeneration while preserving the subepithelial superficial lamina propria, necessary for phonatory mucosal pliability, vocal fold vibration, and optimal vocal function.

Imaging of the calf vocal fold with high-frequency ultrasound

OBJECTIVES/HYPOTHESIS

High-frequency ultrasound imaging offers the potential for assisting in the diagnosis and treatment of vocal fold pathology if it allows aspects of vocal fold microstructure to be visualized noninvasively. The objective of this study was to assess the ability of high-frequency ultrasound to image vocal fold anatomy and injected biomaterials.

STUDY DESIGN

The vocal folds of two excised calf larynges were imaged ex vivo and compared with corresponding histological sections.

METHODS

High-frequency ultrasound imaging was performed under saline submersion using 40 and 50 MHz transducers, and corresponding cryostat cross-sections were stained with H&E, Trichome, and Verhoeff's Van Gieson stains.

RESULTS

The epithelial surface, lamina propria, and underlying muscle were easily identified with the high-frequency ultrasound as verified with histological sections representing each imaged region. The arytenoid cartilage vocal process can also be clearly distinguished from the surrounding tissue, as can the full extent of injected biomaterials within the superficial lamina propria. Useful ultrasound resolution was obtained to depths of at least 10 mm within the tissue with the 40 MHz transducer.

CONCLUSIONS

This preliminary study demonstrates the capability of high-frequency ultrasound to image the layered anatomy of the calf vocal fold and to discern materials injected into the superficial lamina propria, indicating that this technology holds a strong potential for use in phonosurgery.

Photoangiolytic Laser Treatment of Early Glottic Cancer: A New Management Strategy

The 532 nm pulsed KTP (potassium titanyl phosphate) laser and the 585 nm pulsed dye laser (PDL) are photoangiolytic lasers that have been demonstrated to be effective for managing vocal fold dysplasia. The putative mechanism of action is selective photoangiolysis of the sublesional microcirculation. On the basis of this experience, early glottic cancers were treated by selectively targeting the intralesional and sublesional microvasculature. This approach was derived from Folkman's concepts of neoplastic growth resulting from tumor angiogenesis. Staged microlaryngeal treatment was adopted, because it facilitated optimal functional results, and was considered safe, because early glottic cancer rarely metastasizes. Furthermore, intercurrent disease during conventional incremental radiotherapy is typical in treating early glottic cancer. A pilot group of 22 patients with early glottic cancer (13 T1, 9 T2) were treated with a fiber-based angiolytic laser. Eleven of the 22 had unilateral disease and were entirely treated by laser photoangiolysis as a sole modality. Eleven of the 22 had bilateral disease; 5 of the 11 were treated entirely (bilaterally) by laser photoangiolysis, and 6 of the 11 only underwent laser treatment of the less involved vocal fold, with conventional resection being done on the dominant side of the cancer. The initial 8 of the 22 were treated with the PDL, and the latter 14 of the 22 were treated with the pulsed KTP laser. No patient has cancer presently, and none have undergone posttreatment radiotherapy or open surgery. The mean follow-up is 27 months, 13 of the 22 patients have at least 2 years of follow-up, and the first patient was treated just over 5 years ago. Objective measures of vocal function revealed that photoangiolytic treatment of early glottic cancer resulted in significant postoperative improvements despite the fact that half of the patients had bilateral disease. Angiolytic lasers effectively involuted early glottic cancer, with microsurgically directed nonionizing radiation of the dense neoplastic blood supply resulting in complete tumor regression. This approach is conceptually attractive, because it is repeatable, it preserves all conventional cancer treatment options, and it results in excellent vocal function by improving phonatory mucosal wave vibration. Observations from this investigation suggest that this new and novel cancer treatment strategy is effective; however, larger patient cohorts, longer follow-up, and multi-institutional confirmation will be necessary to establish incontrovertible oncological efficacy.

Photoangiolytic Laser Treatment of Early Glottic Cancer: A New Management Strategy

The 532 nm pulsed KTP (potassium titanyl phosphate) laser and the 585 nm pulsed dye laser (PDL) are photoangiolytic lasers that have been demonstrated to be effective for managing vocal fold dysplasia. The putative mechanism of action is selective photoangiolysis of the sublesional microcirculation. On the basis of this experience, early glottic cancers were treated by selectively targeting the intralesional and sublesional microvasculature. This approach was derived from Folkman's concepts of neoplastic growth resulting from tumor angiogenesis. Staged microlaryngeal treatment was adopted, because it facilitated optimal functional results, and was considered safe, because early glottic cancer rarely metastasizes. Furthermore, intercurrent disease during conventional incremental radiotherapy is typical in treating early glottic cancer. A pilot group of 22 patients with early glottic cancer (13 T1, 9 T2) were treated with a fiber-based angiolytic laser. Eleven of the 22 had unilateral disease and were entirely treated by laser photoangiolysis as a sole modality. Eleven of the 22 had bilateral disease; 5 of the 11 were treated entirely (bilaterally) by laser photoangiolysis, and 6 of the 11 only underwent laser treatment of the less involved vocal fold, with conventional resection being done on the dominant side of the cancer. The initial 8 of the 22 were treated with the PDL, and the latter 14 of the 22 were treated with the pulsed KTP laser. No patient has cancer presently, and none have undergone posttreatment radiotherapy or open surgery. The mean follow-up is 27 months, 13 of the 22 patients have at least 2 years of follow-up, and the first patient was treated just over 5 years ago. Objective measures of vocal function revealed that photoangiolytic treatment of early glottic cancer resulted in significant postoperative improvements despite the fact that half of the patients had bilateral disease. Angiolytic lasers effectively involuted early glottic cancer, with microsurgically directed nonionizing radiation of the dense neoplastic blood supply resulting in complete tumor regression. This approach is conceptually attractive, because it is repeatable, it preserves all conventional cancer treatment options, and it results in excellent vocal function by improving phonatory mucosal wave vibration. Observations from this investigation suggest that this new and novel cancer treatment strategy is effective; however, larger patient cohorts, longer follow-up, and multi-institutional confirmation will be necessary to establish incontrovertible oncological efficacy.

Comparison of High-Speed Digital Imaging with Stroboscopy for Laryngeal Imaging of Glottal Disorders

Objectives:

High-speed digital imaging (HSDI), unlike stroboscopy, is a frequency-independent visualization technique that provides detailed biomechanical assessment of vocal physiology due to increased temporal resolution. The purpose of this study was to investigate the clinical value of HSDI compared to that of stroboscopy across 3 disorder groups classified as epithelial, subepithelial, and neurologic disorders.

Methods:

Judgments of vibratory features of vocal fold edge, glottal closure, phase closure, vertical level, vibratory amplitude, mucosal wave, phase symmetry, tissue pliability, and glottal cycle periodicity from 252 participants were performed by 3 experienced raters.

Results:

The results revealed that 63% of the data set was noninterpretable for assessment of vibratory function on stroboscopic analysis because of the severity of the voice disorder (100% of participants with severe voice disorders and 64% of participants with moderate voice disorders), whereas HSDI resulted in analysis of 100% of the data. The neuromuscular group (74%) was the most difficult to analyze with stroboscopy, followed by the epithelial (58%) and subepithelial groups (53%), secondary to the severity of hoarseness.

Conclusions:

Because it is desirable in clinical examination to observe vocal fold vibrations, which cannot be done in cases of severe dysphonia, HSDI may aid in clinical decision-making when patients exhibit values exceeding 0.87% jitter, 4.4% shimmer, and a signal-to-noise ratio of less than 15.4 dB on acoustic analysis. These measures could serve as minimal indications for use of HSDI. The data suggest that HSDI can be viewed as augmentative to stroboscopy, particularly in cases of moderate to severe aperiodicity, in which HSDI may aid clinical decision-making.

Voice function following CO2 laser microsurgery for precancerous and early-stage glottic carcinoma

CONCLUSIONS

With the cover layer injured, vocal function of mucosal ablation could be protected and even return to normal after surgery and vocal function of mucosal stripping was slightly affected with extensive mucosal injury. Once the body layer was injured, the compensatory mechanism would play an important role in phonation.

OBJECTIVES

To investigate voice function following CO2 laser microsurgery for precancerous and early-stage glottic carcinoma.

PATIENTS AND METHODS

Vocal function was examined by acoustic analysis, aerodynamic analysis and videostroboscopic examination.

RESULTS

For mucosal ablation, vocal quality recovered 1 month after surgery. For mucosal stripping, although vocal quality was steady 3 months after surgery, slight hoarseness persisted in this group. The contour of the treated fold recovered postoperatively. There were no complications in recovery. For cordectomies, vocal quality became steady 6 months after the surgery. The supraglottal hyperfunction with supraglottal structure squeezing played an important role in phonation. The affected vocal fold mucosal wave was absent instead of a regular ventricular fold wave or mucosal wave of the vocal process during phonation. In comparison with the type III-IV cordectomy, the results of extended cordectomies (type Va and Vc) were worse; however, the difference was not statistically significant. Granulomas and anterior commissure webs were present. All granulomas resolved spontaneously 3 months postoperatively.

Office-based laryngeal laser surgery with local anesthesia

PURPOSE OF REVIEW

Office-based laryngeal laser surgery was created recently and is emerging as a reliable and practical method of treating a number of laryngeal lesions. This style of minimally invasive surgery is becoming increasingly popular in the United States and abroad.

RECENT FINDINGS

Fiber-based lasers and distal-chip flexible endoscopy have facilitated a new style of surgery. Epithelial diseases such as dysplasia and papillomatosis are well suited for treatment. Although the initial angiolytic laser used was a 585-nm pulsed-dye laser, the 532-nm pulsed-potassium-titanyl-phosphate laser has been demonstrated to be more effective. The 2013-nm Thulium laser shows promise as an office-based laser that simulates the properties of the carbon dioxide laser.

SUMMARY

Evolving technologies to enhance laryngoscopic imaging and lasers along with socioeconomic forces should lead to increasing numbers of laryngeal procedures being performed in the office with local anesthesia.

Effects of 532 nm pulsed-KTP laser parameters on vessel ablation in the avian chorioallantoic membrane: implications for vocal fold mucosa

OBJECTIVES

Selective vascular ablation (photoangiolysis) using pulsed lasers that target hemoglobin is an effective treatment strategy for many vocal fold lesions. However, vessel rupture with extravasation of blood reduces selectivity for vessels, which is frequently observed with the 0.45-ms, 585-nm pulsed dye laser. Previous studies have shown that vessel rupture is the result of vaporization of blood, an event that varies with laser pulse width and pulse fluence (energy per unit area). Clinical observations using a 532-nm wavelength pulsed potassium-titanyl-phosphate (KTP) laser revealed less laser-induced hemorrhage than the pulsed dye laser. This study investigated settings for the pulsed KTP laser to achieve selective vessel destruction without rupture using the avian chorioallantoic membrane under conditions similar to flexible laryngoscopic delivery of the laser in clinical practice.

STUDY DESIGN

The chick chorioallantoic membrane offers convenient access to many small blood vessels similar in size to those targeted in human vocal fold. Using a 532-nm pulsed KTP laser, pulse width, pulse energy, and working distance from the optical delivery fiber were varied to assess influence on the ability to achieve vessel coagulation without vessel wall rupture.

METHODS

Third-order vessels (n = 135) were irradiated: Energy (471-550 mJ), pulse width (10, 15, 30 ms), and fiber-to-tissue distance (1 mm, 3 mm) were varied systematically.

RESULTS

Selective vessel destruction without vessel wall rupture was more often achieved by increasing pulse width, increasing the fiber-to-tissue distance, and decreasing energy. Vessel destruction without rupture was consistently achieved using 15- or 30-ms pulses with a fiber-to-tissue distance of 3 mm (pulse fluence of 13-16 J/cm).

CONCLUSIONS

This study substantiates our clinical observation that a 532-nm pulsed KTP laser was effective for ablating microcirculation while minimizing vessel wall rupture and hemorrhage.

Acoustic Analysis Findings in Objective Laryngopharyngeal Reflux Patients

OBJECTIVE

The aim of this study was to identify the effects of objective laryngopharyngeal reflux (LPR) on the acoustic parameters of patients by comparing their voice samples with that of control subjects.

STUDY DESIGN

Prospective study in two tertiary reference hospitals.

METHODS

48 consecutive patients with symptoms related to LPR and 64 control subjects were included in the study. Suspected LPR patients underwent a 24-hour ambulatory pH monitoring, and 25 (52%) of them were shown to have objective LPR. Acoustical evaluation results of objective LPR patients were compared with that of symptomatic LPR patients and control subjects.

RESULTS

All frequency perturbation values obtained from objective and symptomatic LPR patients were higher than the control subjects (P<0.01). Mean fundamental frequency, amplitude perturbation measures, and noise-to-harmonics ratio were not significantly different between groups.

CONCLUSION

LPR patients have significantly different frequency perturbation values than control subjects.

The Evaluation of Benign Glottic Lesions: Rigid Telescopic Stroboscopy Versus Suspension Microlaryngoscopy

Rigid telescopic strobo-video-laryngoscopy (RTS) is a primary clinical assessment methodology in the office evaluation of benign glottic lesions. However, diagnostic observations can be made only at the time of suspension microlaryngoscopy (SML). The records of 100 consecutive patients undergoing microlaryngoscopy for benign glottic lesions were retrospectively reviewed. Nine of 100 patients were found to have additional glottic lesions during SML. Sixteen additional lesions were noted in these nine patients. Fifteen of 16 lesions were sulci and/or mucosal bridges. Forty-five percent (4/9) of the patients with additional lesions underwent a management change intraoperatively. Three patients underwent additional surgical dissection, and one underwent less dissection than was planned. The discrepancy in diagnosis between rigid telescopic strobo-video-laryngoscopy and suspension microlaryngoscopy highlights certain key points: (1) During office endoscopy, tangential views of the medial surface of the glottis limit the diagnostic sensitivity. (2) Sulci and mucosal bridges are most subject to this limitation. (3) Informed consent should address the potential need for a change in intraoperative management. It is advisable to discuss the possibility for dissection in both vocal folds, even if a unilateral lesion is observed in the office. (4) Microlaryngoscopy is the final diagnostic step in the evaluation of glottic pathology. Meticulous inspection and palpation of the glottis are recommended during SML.