Surgical Therapy of T1 and Selected Cases of T2 Glottic Carcinoma: Cordectomy, Horizontal Glottectomy and CO2 Laser Endoscopic Resection

Aims and background

Among the different laryngeal neoplasms, glottic carcinoma is known to be one of the most suitable for functional management. Nevertheless, the best treatment for T1 and T2 glottic carcinoma, whether an open neck procedure, endoscopy or radiotherapy, with reference to recurrence, survival, and functional results, has long been debated.

Study design

From February 1983 to September 1997, 83 patients with well to undifferentiated glottic carcinoma (48 pT1a, 14 pT1b, and 21 selected cases of pT2 with impairment of vocal cord mobility) were submitted to surgery at the Otorhinolaryngologic Section of the Department of Surgical Sciences and Organ Transplantations of Cagliari University. Surgical treatment included 30 laryngofissures with simple or enlarged cordectomy, 22 horizontal glottectomies and 31 endoscopic laser resections. A retrospective review of the records of the patients was performed in order to obtain a better understanding of the outcome of the three different surgical procedures in our institution.

Results

According to the Kaplan-Meier method, the probability of remaining free of local recurrence 3 years after primary surgery was 0.90 for the T1 group and 0.85 for the T2 group. The distribution of recurrences for cordectomy, glottectomy and CO2 laser at 3 years showed a cumulative probability of remaining free of disease after primary surgery of 0.86, 0.85 and 0.88. The probability of remaining free of local recurrence 3 years after salvage surgery was 0.96 for the T1 group and 0.95 for the T2 group. Analyzing the phenomena for type of surgical procedure, local control at 3 years after salvage surgery for cordectomy, glottectomy and exclusive CO2 laser was 0.93, 0.90 and 0.92, respectively. In the endoscopic group, local control rate after any type of salvage therapy modified the percentage at 3 years to 100%. Anterior commissure spread (AC1-AC2) resulted in a difference (not statistically significant) in local control between the group of patients without and with anterior commissure involvement. Laryngeal preservation was achieved in 93.7% (45/48) of patients who survived after salvage surgery following open neck procedures and in 100% of patients originally submitted to the endoscopic approach.

Conclusions

In our experience, although open laryngeal procedures can be still considered a valid option in the treatment of T1 and selected cases of T2 glottic carcinoma, endoscopic laser excision offered an oncologically adequate alternative to the traditional techniques, with minimum discomfort for the patient and satisfactory preliminary functional results.

Computational modeling of phonatory dynamics in a tubular three-dimensional model of the human larynx

Simulation of the phonatory flow-structure interaction has been conducted in a three-dimensional, tubular shaped laryngeal model that has been designed with a high level of realism with respect to the human laryngeal anatomy. A non-linear spring-based contact force model is also implemented for the purpose of representing contact in more general conditions, especially those associated with three-dimensional modeling of phonation in the presence of vocal fold pathologies. The model is used to study the effects of a moderate (20%) vocal-fold tension imbalance on the phonatory dynamics. The characteristic features of phonation for normal as well as tension-imbalanced vocal folds, such as glottal waveform, glottal jet evolution, mucosal wave-type vocal-fold motion, modal entrainment, and asymmetric glottal jet deflection have been discussed in detail and compared to established data. It is found that while a moderate level of tension asymmetry does not change the vibratory dynamics significantly, it can potentially lead to measurable deterioration in voice quality.

Sensitivity of vocal fold vibratory modes to their three-layer structure: implications for computational modeling of phonation

The sensitivity of the eigenmodes and eigenfrequencies of the human vocal fold to its three-layer structure is studied using finite-element modeling. The study covers a variety of three-dimensional vocal fold models ranging from an idealized, longitudinally uniform structure to a physiologically more realistic, longitudinally varying structure. Geometric parameters including the thickness of the ligament and cover layers as well as the ligament length are varied systematically. The results indicate that vocal fold vibratory modes are quite insensitive to the longitudinal variation in the thickness of the three layers as well as the variation in ligament length. However, significant overall changes in thickness of each layer can produce noticeable changes in these modes. The implications of these findings on computational modeling of phonation are discussed.

Direct-numerical simulation of the glottal jet and vocal-fold dynamics in a three-dimensional laryngeal model

An immersed-boundary method based flow solver coupled with a finite-element solid dynamics solver is employed in order to conduct direct-numerical simulations of phonatory dynamics in a three-dimensional model of the human larynx. The computed features of the glottal flow including mean and peak flow rates, and the open and skewness quotients are found to be within the normal physiological range. The flow-induced vibration pattern shows the classical "convergent-divergent" glottal shape, and the vibration amplitude is also found to be typical for human phonation. The vocal fold motion is analyzed through the method of empirical eigenfunctions and this analysis indicates a 1:1 modal entrainment between the "adduction-abduction" mode and the "mucosal wave" mode. The glottal jet is found to exhibit noticeable cycle-to-cycle asymmetric deflections and the mechanism underlying this phenomenon is examined.

A computational study of asymmetric glottal jet deflection during phonation

Two-dimensional numerical simulations are used to explore the mechanism for asymmetric deflection of the glottal jet during phonation. The model employs the full Navier-Stokes equations for the flow but a simple laryngeal geometry and vocal-fold motion. The study focuses on the effect of Reynolds number and glottal opening angle with a particular emphasis on examining the importance of the so-called "Coanda effect" in jet deflection. The study indicates that the glottal opening angle has no substantial effect on glottal jet deflection. Deflection in the glottal jet is always preceded by large-scale asymmetry in the downstream portion of the glottal jet. A detailed analysis of the velocity and vorticity fields shows that these downstream asymmetric vortex structures induce a flow at the glottal exit which is the primary driver for glottal jet deflection.

A computational study of the effect of vocal-fold asymmetry on phonation

Unilateral laryngeal paralysis leads to tension imbalance and hence to asynchronous movements between the two vocal folds during phonation. In the current study, a computational model of phonation that couples a two-mass model of the vocal folds with a Navier-Stokes model of the glottal airflow, has been used to examine the dynamics of vocal fold configurations with tension imbalance and its implications for phonation. The simulations show that tension imbalance influences phonation onset, intensity as well as the fundamental phonation frequency. Distinct non-linear effects such as period-doubling bifurcation and preferential frequency selection are also observed.

Quantification of static and dynamic supraglottic activity

For estimating supraglottic compression in disordered voice production, categorical rating scales of true vocal fold coverage by supraglottic structures are the current standard. Quantification of change in the position of supraglottic structures compared to no supraglottic activity would be a better method for distinguishing between and within voice-disordered groups. This study developed a method for quantifying static supraglottic activity and extent of false vocal fold (FVF) motion during dynamic supraglottic activity. Twelve control participants and 12 individuals with voice disorders (6 with complaints of vocal fatigue and 6 with vocal fold nodules) were enrolled in the study. These individuals participated in a transnasal fiberoptic laryngeal examination in which various speech tasks were recorded. Single-frame images were selected to represent the positions of minimum and maximum supraglottic compression for each speech task. Two individuals rated these single-frame images using a categorical rating scale. Two other individuals measured the anterior-to-posterior (A-P) distance, vocal fold length, and vocal fold area. A-P and FVF compression were derived from these three measures. Reliability was demonstrated between judges for the ratings and between and within judges for the measures. Significant differences in normalized static supraglottic compression measures corresponded to the rating scale categories. Significant differences in normalized dynamic supraglottic compression measures corresponded to the differences in category ratings between minimum and maximum compression. Using the normalized measures, the voice-disordered groups demonstrated significantly greater static A-P compression (t test, p < .03) than did the control participants. These results suggest that static supraglottic activity may be diagnostic of voice disorder. Normalized dynamic FVF compression ratios were not significantly different between groups. This supports a previous hypothesis that dynamic supraglottic activity serves as an articulatory function at the level of the larynx and is part of the linguistic/phonemic system, rather than evidence of disordered laryngeal function.

Endoscopic inferior turbinate reduction: an outcomes analysis

OBJECTIVES/HYPOTHESIS

In a previous publication, we introduced an endoscopic technique for the treatment of nasal obstruction caused by inferior turbinate hypertrophy. The technique, a modification of the procedure popularized by Mabry, involves resecting the inferior and lateral aspects of the inferior turbinate with a microdebrider under endoscopic guidance. Our preliminary postoperative results were favorable. All 20 patients experienced improvement by postoperative day 5 and the incidence of complications over the first 6 months after surgery was low. The objective of this study is to perform a long-term outcomes analysis of patients undergoing the procedure.

STUDY DESIGN

Follow-up survey questionnaire and analysis.

METHODS

We sent questionnaires to 60 patients, ranging from 6 to 40 months after surgery, inquiring about continued use of nasal medications, need for further surgery, presence of adverse effects, and improvement in symptoms. Nasal airway obstruction was assessed on a subjective scoring scale from 1 (no obstruction) to 6 (complete obstruction).

RESULTS

Of the 28 (47%) patients who returned questionnaires, the severity of daytime nasal obstruction was rated as 2.3 and nighttime nasal obstruction as 2.7. The use of nasal steroids and oral decongestants was 25% and 21%, respectively. Adverse effects were minimal and all but one patient (96%) experienced improvement in their nasal airway.

CONCLUSION

These results confirm the long-term effectiveness of this procedure for the relief of nasal obstruction.

Assessment of posterior cricoarytenoid botulinum toxin injections in patients with abductor spasmodic dysphonia

In this study, we compared 2 techniques for injection of botulinum toxin type A (Botox) into the posterior cricoarytenoid (PCA) muscle for the treatment of abductor spasmodic dysphonia (ABSD). Fifteen patients with ABSD were enrolled in a prospective randomized crossover treatment trial comparing the 2 injection techniques. The PCA muscle was injected with 5 units on each side, with the injections staged 2 weeks apart, via either a percutaneous posterior-lateral approach or a transnasal fiberoptic approach. Eleven patients reported some benefit with the injections; however, the patient-perceived benefits were not related to changes in symptoms on blinded counts by speech pathologists. No significant reductions in the numbers of breathy breaks occurred with either technique, and no differences were found between techniques. Although patients perceived a benefit, blinded symptom counts did not substantiate these benefits. Thus, PCA muscle injections of Botox provided limited benefits to patients with ABSD, demonstrating the need for a more effective therapy for these patients.

Adductor muscle activity abnormalities in abductor spasmodic dysphonia

OBJECTIVE

To determine laryngeal muscle activation abnormalities associated with speech symptoms in abductor spasmodic dysphonia (ABSD).

STUDY DESIGN

Bilateral laryngeal muscle recordings from the posterior cricoarytenoid, thyroarytenoid, and cricothyroid muscles were conducted in 12 ABSD patients. Patients' measures were compared during speech breaks and during speech without breaks and with 10 normal controls.

RESULTS

Significant group differences were found in the thyroarytenoid muscle; the patients had significantly greater activity on the right side both during speech breaks and nonbreaks in comparison with the controls. Cricothyroid muscle levels were also increased on the right in the patients.

CONCLUSION

An asymmetry in adductor muscle tone between the 2 sides in ABSD may account for difficulties with maintaining phonation and voice onset after voiceless consonants.

SIGNIFICANCE

These abnormalities may indicate why PCA BOTOX injections have not been as effective in ABSD as thyroarytenoid injections have been in adductor spasmodic dysphonia.

Modulation of laryngeal responses to superior laryngeal nerve stimulation by volitional swallowing in awake humans

Laryngeal sensori-motor closure reflexes are important for the protection of the airway and prevent the entry of foreign substances into the trachea and lungs. The purpose of this study was to determine how such reflexes might be modulated during volitional swallowing in awake humans, when persons are at risk of entry of food or liquids into the airway. The frequency and the amplitude of laryngeal adductor responses evoked by electrical stimulation of the internal branch of the superior laryngeal nerve (ISLN) were studied during different phases of volitional swallowing. Subjects swallowed water on command while electrical stimuli were presented to the ISLN at various intervals from 500 ms to 5 s following the command. Laryngeal adductor responses to unilateral ISLN stimulation were recorded bilaterally in the thyroarytenoid muscles using hooked wire electrodes. Early ipsilateral R1 responses occurred at 17 ms, and later bilateral R2 began around 65 ms. The muscle responses to stimuli occurring during expiration without swallowing were quantified as control trials. Responses to stimulation presented before swallowing, during the swallow, within 3 s after swallowing, and between 3 and 5 s after a swallow were measured. The frequency and amplitude of three responses (ipsilateral R1 and bilateral R2) relative to the control responses were compared across the different phases relative to the occurrence of swallowing. Results demonstrated that a reduction occurred in both the frequency and amplitude of the later bilateral R2 laryngeal responses to electrical stimulation for up to 3 s after swallowing (P = 0.005). The amplitude and frequency of ipsilateral R1 laryngeal responses, however, did not show a significant main effect following the swallow (P = 0.28), although there was a significant time by measure interaction (P = 0.006) related to reduced R1 response amplitude up to 3 s after swallowing (P = 0.021). Therefore, the more rapid and shorter unilateral R1 responses continued to provide some, albeit reduced, laryngeal protective functions after swallowing, whereas the later bilateral R2 responses were suppressed both in occurrence and amplitude for up to 3 s after swallowing. The results suggest that R2 laryngeal adductor responses are suppressed following swallowing when residues may remain in the laryngeal vestibule putting persons at increased risk for the entry of foreign substances into the airway.

Early arytenoid adduction for vagal paralysis after skull base surgery

OBJECTIVES

To evaluate the efficacy of early arytenoid adduction in the management of vagal paralysis after skull base surgery.

STUDY DESIGN

Retrospective evaluation at a tertiary care skull base center.

METHODS

Aggressive surgical management of skull base lesions has become increasingly popular owing to advances in surgical technique and intraoperative monitoring. Temporary and permanent lower cranial neuropathies occur frequently, especially after the surgical management of lesions involving the vertebrobasilar system and the jugular foramen. An injury to the proximal vagus nerve is usually associated with dysphonia and swallowing dysfunction. An early arytenoid adduction has been employed in 26 patients with a vagal paralysis after skull base surgery. Most commonly, the neurosurgical patient underwent an arytenoid adduction under general anesthesia on postoperative day 2.

RESULTS

Videostroboscopy after arytenoid adduction demonstrated 76% of patients had complete glottic closure. Of those with inadequate glottic closure, all demonstrated a well-medialized posterior glottis with a persistent anterior glottal gap. These patients were easily treated with a secondary type I thyroplasty under local anesthesia with sedation resulting in complete glottic closure. Despite excellent voice outcomes, 66% of these patients had dysphagia requiring enteral feedings for nutritional support.

CONCLUSIONS

An early arytenoid adduction is an excellent medialization technique that can be performed safely in the early postoperative period under general anesthesia after skull base surgery.

Endoscopic revision of failed external dacryocystorhinostomy

Obstruction of the lacrimal pathways is a relatively frequent problem usually corrected by external dacryocystorhinostomy. Failure of the external approach may be due to an inadequate rhinostomy, excessive scar tissue production, anatomical anomalies or concomitant paranasal sinus infectious. The introduction of direct and angled endoscopes for paranasal sinus surgery and the refinement of endoscopic surgical procedures allows a complete intranasal exposure and surgical management of the lacrimal sac, even in cases of recurrent obstruction. The present work offers a retrospective review of the records of seven patients who underwent a revision endoscopic dacriocystorhinostomy (ENDCR) between January 1994 and June 1997 for failed external dacryocystorhinostomy. The preoperative evaluation of the patients, the surgical technique and the postoperative management are examined in detail. A permanent dacryocystorhinostomy was obtained in six patients. One patient underwent a successful bilateral procedure. One patient experienced a persistent stenosis. There were no complications related to the surgical procedure. In our experience the revision endoscopic dacryocystorhinostomy offered several advantages, including a complete exposure of those anatomical anomalies or inflammatory changes of the normal structures that commonly hinder conventional external surgery. Although a larger series will further elucidate the efficacy of this procedure in failed external dacryocystorhinostomy, we recommend considering revision ENDCR as an alternative to the external revision technique.

Effects of botulinum toxin on pathophysiology in spasmodic dysphonia

To determine the mechanism of symptom relief with treatment by botulinum toxin injection in persons with adductor spasmodic dysphonia (ADSD), we evaluated the effects of unilateral thyroarytenoid muscle injections on both injected and noninjected muscles in 10 subjects with ADSD, using electromyography on both sides of the larynx before and after treatment. The subjects' speech symptoms were reduced (p = .005) 2 weeks following injection, when the electromyographic study occurred. Muscle activation levels and the numbers of spasmodic muscle bursts decreased significantly (p < or = .03) postinjection in both the injected and noninjected muscles. The reductions in laryngeal muscle bursts correlated with symptom reduction (r > or = .7) in all muscles. Reductions in laryngeal muscle bursts did not relate to either absolute or normalized levels of muscle activity before or after botulinum toxin injection. The results suggest that changes in the central pathophysiology are responsible for changes in speech symptoms following treatment.

Chronic intermittent stimulation of the thyroarytenoid muscle maintains dynamic control of glottal adduction

Patients with laryngeal motor control disorders need improved dynamic glottal closure for speech and swallowing. To evaluate the functional outcome of intermittent chronic thyroarytenoid muscle stimulation in an animal model, 6 canines were implanted with bilateral Medtronic Xtrel systems containing Peterson-type electrodes in the inferior and superior portions of the thyroarytenoid muscle. Stimulation was on one side only at 60 Hz, for 5 s on and 5 s off, over 8 h, 5 days per week, up to 8 months. Monthly videorecordings were done under anesthesia to measure the voltage threshold for detectable movement on each side, and vocal fold displacement and velocity during maximal stimulation of each side. Movement thresholds were lower in the inferior portion of the thyroarytenoid muscle (P </= 0.0005). Movement velocity was greater on the stimulated than on the nonstimulated side after 3 to 8 months (P = 0.039). No differences in the percentage distribution of different myosin heavy chain types were found between the stimulated and nonstimulated muscle samples. Sustained dynamic glottal adduction with no alteration in thyroarytenoid muscle function or fiber type was achieved with intermittent stimulation over 8 months. The results suggest that chronic intermittent thyroarytenoid stimulation has good potential for improving airway protection in dysphagia.

Laryngeal long latency response conditioning in abductor spasmodic dysphonia

Previously, we demonstrated that patients with adductor spasmodic dysphonia (ADSD) have a disinhibition of laryngeal responses to sensory input. In this study, sensorimotor responses to stimulation of the superior laryngeal nerve were compared between 10 subjects with abductor spasmodic dysphonia (ABSD) and 15 normal volunteers. The groups had similar latency and frequency characteristics of their unconditioned adductor responses (p>.05). The conditioned R1 (early) responses of the subjects with ABSD were greater and more variable in amplitude than those of the normal volunteers (p< or =.008). Similar R2 (late) conditioning effects were found in both groups, with a nonsignificant trend toward reduced inhibition of contralateral R2 responses at lower interstimulus intervals (p = .01) in the patient group. Thus, inhibitory mechanisms that modulate the R1 laryngeal sensorimotor pathway in the brain stem may be abnormal in subjects with ABSD. Abnormal modulation of laryngeal sensorimotor responses seems present in both types of spasmodic dysphonia.

Exit jet particle velocity in the in vivo canine laryngeal model with variable nerve stimulation

This study extends previous work on exit jet particle velocity in the in vivo canine model of phonation by measuring air particle velocity at multiple locations in the midline of the glottis and across multiple levels of recurrent laryngeal nerve (RLN) and superior laryngeal nerve (SLN) stimulation. In a second experiment, exit jet particle velocity was measured at midline and offmidline positions with constant levels of RLN and SLN stimulation. In this study, peak particle velocity was higher at the anterior commissure than at the posterior commissure in the midline of the glottis, and peak particle velocity was higher at the midline than at offmidline positions. In addition, increasing levels of RLN stimulation resulted in increasing peak particle velocity; however, increasing levels of SLN stimulation failed to produce a uniform effect on peak particle velocity.

Three-dimensional changes in the upper airway during neuromuscular stimulation of laryngeal muscles

During swallowing, airway protection depends upon adequate glottal closure and laryngeal elevation to prevent the entry of substances into the airway. Three-dimensional changes in the upper airway during laryngeal muscle stimulation in a canine model were quantified in animals implanted with Peterson type stimulating electrodes in the inferior and superior portions of the thyroarytenoid muscle, together with a reference electrode. Computer tomography scanning was performed on an IMATRON scanner with a 3 mm slice thickness advanced at overlapping 1 mm increments. Stimulation of the thyroarytenoid muscle produced adductions of the vocal fold towards the midline and changes in the supraglottic region as well as the glottis; the glottic wall was compressed medially above and below the glottis. These results suggest that chronic neuromuscular stimulation can effect glottic protection by reducing the glottal opening and may be beneficial for patients with central control disorders affecting airway protection during swallowing.

Comparison of voice analysis systems for perturbation measurement

Dysphonic voices are often analyzed using automated voice analysis software. However, the reliability of acoustic measures obtained from these programs remains unknown, particularly when they are applied to pathological voices. This study compared perturbation measures from CSpeech, Computerized Speech Laboratory, SoundScope, and a hand marking voice analysis system. Sustained vowels from 29 male and 21 female speakers with mild to severe dysphonia were digitized, and fundamental frequency (F0), jitter, shimmer, and harmonics- or signal-to-noise ratios were computed. Commercially available acoustical analysis programs agreed well, but not perfectly, in their measures of F0. Measures of perturbation in the various analysis packages use different algorithms, provide results in different units, and often yield values for voices that violate the assumption of quasi-periodicity. As a result, poor rank order correlations between programs using similar measures of perturbation were noted. Because measures of aperiodicity apparently cannot be reliably applied to voices that are even mildly aperiodic, we question their utility in quantifying vocal quality, especially in pathological voices.

A comparison of type I thyroplasty and arytenoid adduction

Glottal incompetence is a common laryngeal disorder causing impaired swallowing and phonation. The resultant voice has been characterized as weak and breathy with a restricted pitch range. Currently, medialization thyroplasty and arytenoid adduction are two of the surgical treatments for patients with glottal incompetence. However, few studies have evaluated the changes in objective measures of speech with type I thyroplasty and arytenoid adduction. In this study, 59 patients with glottal incompetence underwent either type I thyroplasty or arytenoid adduction. Acoustic (jitter, shimmer, and harmonics-to-noise ratio) and aerodynamic (airflow, subglottic pressure, and glottal resistance) measures were obtained both pre- and postoperatively. No significant differences were found among acoustic or aerodynamic measures for operation type. However, a significant pre/postsurgery effect was observed for translaryngeal airflow. In addition, no significant differences were found among the measures for patients with traditional compared with nontraditional operative indications. Patients who developed glottal insufficiency due to previous laryngeal surgery (e.g., vocal fold stripping) demonstrated no statistically significant improvement in acoustic or aerodynamic measures following thyroplasty or arytenoid adduction.

Cutaneous neuroendocrine (Merkel cell) carcinoma. A report of 35 cases

Cutaneous neuroendocrine (Merkel cell) cancer (CNEC) is a rare skin tumor with a highly malignant nature. Initial treatment of this tumor has often been limited to a local excision. The medical records of 35 patients diagnosed with CNEC and treated at Southern California Kaiser Permanente Medical Group or UCLA Medical Center between 1980 and 1991 were reviewed. There were 26 male and 9 female patients were enrolled in this study. Minimum follow-up from date of diagnosis was 18 months, mean follow-up was 40 months; 25 patients presented with local disease (stage I) and 10 patients presented with regional disease (involved nodes, stage II). Patients who were treated initially with local therapy alone had a 65% recurrence rate and a 29% mortality rate, while those patients treated locoregionally at presentation had only a 27% recurrence rate and 14% mortality rate, although the majority presented with more advanced disease. Due to the high incidence of lymph node failure and death in patients treated locally versus locoregionally at presentation, we feel that planned locoregional treatment is indicated for all patients presenting with CNEC, regardless of stage.

The effect of gas density on glottal vibration and exit jet particle velocity

Although theoretical studies include a term for gas density in their mathematical descriptions of glottal aerodynamics, the effect of gas density on glottal vibration has not been examined empirically. In this study, an in vivo canine model was used to evaluate the effect of gas density on glottal vibration by comparing phonation with air and helium. With gas flow and nerve stimulation held constant, phonation with helium resulted in an increased exit jet particle velocity for helium (45 m/s) compared to air (34 m/s). However, the measured increase in helium velocity was less than predicted by a proportional relationship between transglottal pressure and dynamic pressure. This difference could be due to a change in the constant of proportionality or in the dynamic pressure loss coefficient associated with the use of helium.

Comparing reliability of perceptual ratings of roughness and acoustic measure of jitter

Acoustic analysis is often favored over perceptual evaluation of voice because it is considered objective, and thus reliable. However, recent studies suggest this traditional bias is unwarranted. This study examined the relative reliability of human listeners and automatic systems for measuring perturbation in the evaluation of pathologic voices. Ten experienced listeners rated the roughness of 50 voice samples (ranging from normal to severely disordered) on a 75 mm visual analog scale. Rating reliability within and across listeners was compared to the reliability of jitter measures produced by several voice analysis systems (CSpeech, SoundScope, CSL, and an interactive hand-marking system). Results showed that overall listeners agreed as well or better than "objective" algorithms. Further, listeners disagreed in predictable ways, whereas automatic algorithms differed in seemingly random fashions. Finally, listener reliability increased with severity of pathology; objective methods quickly broke down as severity increased. These findings suggest that listeners and analysis packages differ greatly in their measurement characteristics. Acoustic measures may have advantages over perceptual measures for discriminating among essentially normal voices; however, reliability is not a good reason for preferring acoustic measures of perturbation to perceptual measures.

Merkel cell carcinoma: an aggressive skin neoplasm

Merkel cell carcinoma (MCC) is an aggressive skin neoplasm of neuroendocrine origin. To clarify those factors important in improving survival, we retrospectively reviewed the charts of all patients with Merkel cell carcinoma treated at two tertiary referral centers. Eighty percent of the patients with stage I disease were initially treated with local therapy alone, while all of the patients with stage II disease were treated with local and regional therapy. The overall survival rate for all patients was 64%. Regardless of stage, patients treated with local excision alone had a 52% 5-year survival rate, while patients treated with local excision and lymph node dissection had an 87% survival rate. We conclude that the aggressive nature of this tumor warrants radical therapy.

Effects of RLN and SLN stimulation on glottal area

In vivo canine experiments have demonstrated that vocal fold stiffness varies proportionately with changing levels of recurrent laryngeal nerve (RLN) and superior laryngeal nerve (SLN) stimulation. This study evaluated the morphologic changes in the glottis at varying levels of nerve stimulation and the presumed effects on laryngeal air particle velocity. Stroboscopic data from the in vivo canine model of phonation were examined under varying conditions of RLN and SLN stimulation. Computerized analysis of stroboscopic images was used to reconstruct the glottal area vs. time waveforms. As RLN stimulation increased, glottal area per cycle decreased (p < 0.05). However, as SLN stimulation increased, glottal area per cycle increased (p < 0.05). However, as SLN stimulation increased, glottal area per cycle increased (p < 0.05). These results support the hypothesis that increasing RLN stimulation at similar levels of SLN stimulation produces an increase in air particle velocity, whereas an increase in SLN stimulation causes a decrease in air particle velocity.

Changes in glottal area associated with increasing airflow

Laryngeal resistance varies inversely with airflow during phonation. This study evaluated the morphological changes in the glottis that accompany decreases in laryngeal resistance at higher levels of airflow. An in vivo canine model of phonation and a video analysis system were used to assess changes in area. Four animals were examined stroboscopically as airflow increased, with constant recurrent laryngeal nerve stimulation. Glottal dynamics were evaluated by means of photoglottography, electroglottography, and measures of subglottic pressure. Analysis of digitized stroboscopic images indicated that increasing airflow had no obvious effect on the glottal chink (vocal process contact). Increasing airflow was associated with an increase in the area of peak opening and an increase in the glottal area integral.

Effect of tension, stiffness, and airflow on laryngeal resistance in the in vivo canine model

This study used an in vivo canine model of phonation to determine the effects of airflow on glottal resistance at low, medium, and high levels of recurrent laryngeal nerve (RLN) and superior laryngeal nerve (SLN) stimulation. Static and dynamic trials of changing airflow were used to study the effects of airflow on glottal resistance during phonation. As reported previously, glottal resistance varies inversely as a function of airflow. Increasing levels of RLN stimulation resulted in a statistically significant increase in glottal resistance for each level of airflow evaluated. Variation in SLN stimulation had no statistically effects on the relationship between flow and resistance. At airflow rates greater than 590 milliliters per second (mL/s), glottal resistance approached 0.1 mm Hg per mL/s for all levels of RLN and SLN stimulation tested. These data support the collapsible tube model of phonation.

Inverting papilloma of the head and neck: the UCLA update

Inverting papilloma of the nose and paranasal sinuses is a benign disease with malignant potential. This disease is characterized by multiple recurrences, especially after minimal operative therapy. Controversy exists over the most appropriate treatment for this rare tumor. This review presents an update of the UCLA experience with inverting papilloma over the past four decades along with a review of the literature. A retrospective study of 61 patients seen at the UCLA Medical Center was conducted. The mean age at presentation was 63 years, with a male-to-female ratio of 2:1. The most common symptom at presentation was nasal obstruction (71%), followed by epistaxis (27%). Seventeen percent of the patients in this series either had concurrent squamous cell carcinoma of the nose or paranasal sinuses, or it developed. Patients treated with a lateral rhinotomy and medial maxillectomy had a recurrence rate of 30 percent. Those treated with a less aggressive operation had a recurrence rate of 71 percent. Despite a trend for a more conservative sinus operation in recent literature, we continue to advocate a lateral rhinotomy and medial maxillectomy as the treatment of choice for inverting papilloma of the head and neck.