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At least 163 records · Page 9Linked to original sources

DiHA (dextranomers in hyaluronan) injections for treatment of insufficient closure of the vocal folds: early clinical experiences.

OBJECTIVE: To determine the clinical effects of injecting DiHA (a mixture of dextranomer molecules and 1% hyaluronan solution in equal proportions) as a "space filler" into the vocal folds of patients experiencing insufficient closure of the vocal folds resulting from either unilateral vocal fold paralysis or bowed vocal folds. STUDY DESIGN: A consecutive series of patients with insufficient closure of the vocal folds treated with DiHA injections and prospectively followed up with videostroboscopy and voice recordings that were evaluated by expert panels. METHODS: During a 21/2-year period, 14 patients with insufficient closure of the vocal folds were included. Six had a unilateral vocal fold palsy and 8 patients had "bowed" vocal folds. DiHA was injected into one vocal fold. Laryngoscopic examination and voice recordings were performed pre- and postoperatively. Expert panels did the evaluation of the stroboscopy examination and the perceptual voice analysis. RESULTS: Three patients were operated on with local and 11 under general anesthesia. All patients with unilateral palsy improved their stroboscopic status regarding both the wave and the closure after injection. Also, their voice parameters were significantly improved. Among the patients with bowed vocal folds, all except 2 showed an improvement in the glottic wave, 5 of 8 improved in glottic closure, and 3 improved their voice parameters significantly. CONCLUSION: This early clinical experience indicates that DiHA fulfills most of the requirements of an ideal "space-filling" substance for voice restoration in patients experiencing insufficient vocal fold closure.

Adult↗

Immediate recurrent laryngeal nerve reconstruction and vocal outcome.

OBJECTIVE: The objective of this prospective study was to assess the long-term effects of immediate reconstruction of the recurrent laryngeal nerve (RLN) during thyroid cancer extirpation on postoperative phonatory function. SUBJECTS AND METHODS: The subjects were 22 patients with advanced thyroid cancer who underwent resection of the primary lesion and involved RLN. RLN paralysis was seen in 12 patients preoperatively and involvement of the RLN was noted intraoperatively in 10. Immediate reconstruction of the RLN was performed on eight patients using the great auricular nerve and one underwent direct anastomosis of the RLN stumps (group I). Nine patients opted not to have phonosurgical procedures (group II). The remaining four had arytenoid adduction immediately after cancer extirpation (group III). Phonatory function (stroboscopy, maximum phonation time [MPT], mean airflow rate [MFR], harmonics-to-noise ratio [HNR], jitter, and shimmer) was followed for at least 9 months. RESULTS: Minimal or no glottal gap during phonation was observed in six patients in group I, whereas the patients in group II had a large gap along the entire fold. HNR, MPT, and MFR were significantly better in group I (17.7 +/- 3.6 dB, 15.1 +/- 6.3 s, and 100 +/- 32 mL/s, respectively) than in group II (12.1 +/- 2.9 dB, 5.4 +/- 3.1 s, and 430 +/- 207 mL/s, respectively). Patients in group III had a gap of varying degrees along the membranous fold. Although HNR, shimmer, and MPT in group III were comparable to group I, the other parameters were less favorable than in group I. CONCLUSION: Immediate RLN reconstruction at the time of thyroid cancer extirpation can provide excellent postoperative phonatory function.

Adult↗

Late voice function after surgical injury to the recurrent nerve.

In the period 1960 to 1970, a total of 213 patients underwent subtotal thyroidectomy for benign cervical toxic goitre. Postoperatively, immobile vocal cord indicating paralysis of the recurrent nerve was found in 17 patients. In 8 patients, immobility of the vocal cord was permanent. Seven of the 17 patients received voice training which was initiated within 3 weeks after operation. After a period of 5-10 years, on an average 8 years, the 17 patients had a clinical and a comprehensive objective examination of the voice function comprising stroboscopy, electroglottography, phono-oscillometry, voice range, phonation time, peak-flow and pitch. Only a few complaints were ciliated whereas the objective examination of the voice function revealed abnormal findings in all but one patient. The findings were less abnormal in patients who had received early voice training. It is concluded that despite abnormal objective findings, all 17 patients found their voice function satisfactory. Moreover, early voice training seemed to offer a fair chance of minimizing late voice problems, whether the paralysis was permanent or transitory.

Adult↗

The role of glottal gap in predicting aspiration in patients with unilateral vocal paralysis.

Aspiration has been frequently noted among patients suffering from vocal-fold paralysis. The association between a defect of glottal closure and aspiration in patients with unilateral vocal paralysis appears to have been rarely reported. The current study reviews collected data consisting of videotaped flexible nasoendoscopy and stroboscopy for patients with a unilateral vocal-fold paralysis. Mean normalized glottal gap areas for patients suffering vocal paralysis with associated aspiration are significant greater than that for the non-aspiration group. Subsequent to the surgical correction of the glottal gap, all patients recovered well from their earlier aspiration. The investigation of objectively derived data revealed that poor airway protection due to incomplete closure of the vocal fold was the major cause of aspiration for patients suffering unilateral vocal-fold paralysis. Intracordal autologous fat injection can successfully improve the breath control and eliminate aspiration in patients with vocal-fold paralysis.

Adult↗

Effect of temperature, nutrients, calcium, and cAMP on motility of human spermatozoa.

The motility of human spermatozoa and its regulation were examined on cells isolated from other seminal components and purified into fractions of uniform progressive motility. The percent motile cells and estimates of their translational speed were determined by visual inspection, by stroboscopy, and by photon correlation spectroscopy; microcinematography and gradient centrifugation were occasionally used to clarify discrepancies. The motility of isolated spermatozoa could be maintained for periods up to 24 h at 4 or 37 degrees C; the presence of seminal fluid was not required and even provoked a reversible inhibition at 4 degrees C. Albumin facilitated cell movement between microscopic glass plates but had no effect on progressive motility per se, as evidenced by other techniques. During incubations of up to 2 h, progressive cell motility occurred independently of extracellular glucose and calcium but responded to variations in adenosine 3',5'-cyclic monophosphate and calcium. Dibutyryl cAMP increased forward motility, whereas ethyleneglycol-bis(beta-aminoethylether)-N,N'-tetraacetic acid reversibly immobilized the spermatozoa in a calcium-dependent manner; phosphodiesterase inhibition resulted in increased vibration of sperm heads without any effect on progressive motility. Longer incubation periods required the presence of extracellular nutrients. These experiments further demonstrate that several motility measuring techniques should be used in parallel to distinguish the various components of cell movement, to exclude aspecific effects, and to supplement the shortcomings of each individual technique. Such procedure could clarify the various discrepancies that have been reported so far and should lead to a better understanding of the regulation of human sperm motility.

Calcium↗

Morphological and functional aspects of the senile larynx.

OBJECTIVE: To analyze the senile larynx, considering morphological aspects during respiration and functional aspects during phonation, comparing it to the young adult larynx. PATIENTS AND METHODS: A retrospective study was conducted of 100 laryngeal images of adults without vocal complaints, 50 laryngeal images of young adults aged 20-45 years and 50 laryngeal images of elderly individuals aged 65-85 years, of both genders. Images were produced by means of a rigid endoscope and stroboscopy. The morphological aspects analyzed were: laryngeal symmetry, vocal fold bowing, prominence of the vocal process and glottic proportion. The functional aspects analyzed were glottic closure, laryngeal vestibule behavior, phase (timing of closure) and amplitude symmetry of mucosal wave and tremor of laryngeal structures. RESULTS: Significant differences between the young adult larynx and the geriatric larynx were found for the following parameters: vocal fold bowing, prominence of the vocal process, glottic proportion, phase and amplitude symmetry of mucosal wave and tremor of laryngeal structures. CONCLUSION: The data suggests that the geriatric larynx differs from the young adult larynx in many characteristic aspects.

Adult↗

The pitch rise paradigm: a new task for real-time endoscopy of non-stationary phonation.

As standard stroboscopy is restricted to the recording of periodic vocal fold vibrations, observations of non-stationary laryngeal mechanisms demand real-time recording systems, the most advanced being the high-speed video technique. It allows the registration of laryngeal parameters during a variation of the fundamental frequency. The aim of this study was to compare amplitude and frequency parameters of vocal fold vibration during stationary and non-stationary phonation, i.e. a monotonous pitch rise. Twenty-nine young female adults with no incidence of voice disorders were examined while performing two different phonation tasks: sustained phonation with a constant frequency and a monotonous pitch rise. Endoscopic recordings and the acoustic signals were acquired simultaneously. Both acoustic and laryngeal parameters were derived for short time intervals of 17.8 ms for the constant pitch and pitch rise conditions. Instantaneous frequency, sound pressure level, vibratory amplitudes of the vocal folds and the type of glottal closure were compared. At the beginning of the pitch rise, the acoustic and laryngeal parameters were similar to the parameters that occurred within the sustained phonation conditions. In contrast, the laryngeal parameters at the middle and at the end of the pitch rise differed substantially from those during sustained phonation. For the first time, quantitative measures of the growing glottal chink and the vibration amplitude decrease during pitch increase could be taken. In general, the image evaluation of the pitch rise paradigm can be subdivided into the starting, the raising and the final phase. As each phase can be considered as quasi-stationary, existing software modules are capable of analysing the process by treating each phase separately. Hence, the pitch rise condition may be suitable for clinical examination to detect information of voice disturbances that cannot be visualized during sustained phonation.

Adolescent↗

Stroboscopic assessment of vocal fold keratosis and glottic cancer.

Disruption of the normal viscoelastic properties of the superficial lamina propria (SLP) results in aberrant vocal fold vibration and mucosal wave propagation. Therefore, an investigation was performed to determine whether stroboscopy is a reliable method for 1) differentiating invasive glottic carcinoma from intraepithelial atypia or 2) determining the depth of cancer invasion. An analysis was done on the preoperative vocal fold vibration characteristics of 62 keratotic (intraepithelial, 45; cancer, 17) lesions that were subsequently resected by means of microlaryngoscopy. Histopathology and intraoperative mapping were used to specify the depth of invasion. A panel of 4 blinded judges was used to assess the amplitude of vocal fold vibration and the magnitude of mucosal wave activity in the region of the lesion from videostroboscopic recordings. The final comparative data set comprised only those ratings that achieved at least 75% interjudge agreement. Of the 28 intraepithelial lesions that could be reliably evaluated for amplitude of vocal fold vibration, only 2 were normal, with the amplitude reduced in 24 and absent in 2. Of the 30 intraepithelial lesions in which mucosal wave activity could be reliably assessed, only 2 were normal, with the wave reduced in 24 and absent in 4. Furthermore, amplitude of vocal fold vibration and magnitude of mucosal wave propagation were absent in 2 of 4 carcinomas in which the depth of microinvasion did not reach the vocal ligament. According to the findings herein, reduced amplitude of vocal fold vibration and/or mucosal wave propagation associated with keratosis did not reliably predict the presence of cancer or the depth of cancer invasion into the laminae propriae. However, the presence of a flexible mucosal wave probably indicates that there is not extensive vocal ligament invasion. Reductions in the amplitude of vocal fold vibration and in mucosal wave magnitude were usually noted in intraepithelial atypia, despite the fact that there was no invasion into the SLP. The reduced epithelial pliability could be due to bulky keratosis and/or alteration of the SLP occurring as a result of inflammation or fibrovascular scarring.

Carcinoma, Squamous Cell↗

Larynx preservation with supracricoid partial laryngectomy with cricohyoidoepiglottopexy. Correlation of videostroboscopic findings and voice parameters.

Classically, the formation of a mucosal wave is dependent on the pliable mucosa present in the vocal fold. The supracricoid partial laryngectomy with cricohyoidoepiglottopexy is an organ preservation surgical technique in which both true vocal folds, both false vocal folds, both paraglottic spaces, and the entire thyroid cartilage are resected. The functional goal is speech and swallowing without a permanent tracheostomy. In an effort to further study voice production in these patients, we performed laryngeal stroboscopy in 5 patients. Analysis was performed with a modified Bless grading system. In addition, speech and voice parameters were also measured and correlated with stroboscopic findings. The key finding in this study was the presence of a periodic mucosal wave on the anterior aspect of the arytenoid cartilage, where it abuts the epiglottic cartilage. Patients with lower periodicity and symmetry scores tended to have lower jitter and shimmer percentages.

Adult↗

Modeling measured glottal volume velocity waveforms.

The source-filter theory of speech production describes a glottal energy source (volume velocity waveform) that is filtered by the vocal tract and radiates from the mouth as phonation. The characteristics of the volume velocity waveform, the source that drives phonation, have been estimated, but never directly measured at the glottis. To accomplish this measurement, constant temperature anemometer probes were used in an in vivo canine constant pressure model of phonation. A 3-probe array was positioned supraglottically, and an endoscopic camera was positioned subglottically. Simultaneous recordings of airflow velocity (using anemometry) and glottal area (using stroboscopy) were made in 3 animals. Glottal airflow velocities and areas were combined to produce direct measurements of glottal volume velocity waveforms. The anterior and middle parts of the glottis contributed significantly to the volume velocity waveform, with less contribution from the posterior part of the glottis. The measured volume velocity waveforms were successfully fitted to a well-known laryngeal airflow model. A noninvasive measured volume velocity waveform holds promise for future clinical use.

Air Movements↗

Findings of multiple muscle involvement in a study of 214 patients with laryngeal dystonia using fine-wire electromyography.

Although perceptual and stroboscopic data help in diagnosing and classifying laryngeal dystonia, these measures do not aid the voice clinician in targeting which specific muscles to treat with botulinum toxin. Most patients achieve smoother, less effortful voicing with standard injection regimens. However, there is a notable failure rate. We performed fine-wire electromyography on 214 consecutive patients with laryngeal dystonia. We correlated voice ratings, stroboscopy data, and fine-wire electromyography data. Videostroboscopy was successful in visually demonstrating most of the audible findings in isolated vocal tremor, but it was much less successful in identifying breaks alone or a combination of breaks and tremor. Fine-wire electromyography revealed that the thyroarytenoid muscle was significantly more likely than the lateral cricoarytenoid muscle to be the predominant muscle associated with adductor spasmodic dysphonia, and that the thyroarytenoid and lateral cricoarytenoid muscles were equally likely to be predominantly involved in tremor spasmodic dysphonia. In addition, several patients in both the adductor spasmodic dysphonia and the tremor spasmodic dysphonia groups presented with interarytenoid muscle predominance. All of the intrinsic laryngeal muscles are capable of being the predominant muscle in laryngeal dystonia, and there are patterns of muscle abnormalities that differ between adductor spasmodic dysphonia and tremor spasmodic dysphonia. Some of the failures in treating adductor spasmodic dysphonia with botulinum toxin, and the greater difficulty with success in treating patients with tremor spasmodic dysphonia, are due to failure to deliver toxin to the appropriate muscles.

Electromyography↗

Photocoagulation of microvascular and hemorrhagic lesions of the vocal fold with the KTP laser.

OBJECTIVES: Ectasias and varices of the vocal fold are microvascular lesions that are often due to chronic abuse of the voice, and are occasionally encountered in association with other disorders such as polyps, Reinke's edema, and hematoma. The KTP laser can be used for photocoagulation of small vascular lesions, because the laser beam is well absorbed by hemoglobin, and damage to the epithelium is minimal. The present pilot study examined how the KTP laser could be used for microvascular lesions and their associated lesions. METHODS: Twelve patients who had undergone phonomicrosurgery were enrolled in the present study. The microvascular lesions were treated by photocoagulation with the laser set at a low power of 1.5 W in the continuous mode, while preserving the epithelium, and associated lesions were then treated by microdissection with cold instruments. The postoperative phonatory function was assessed by maximum phonation time, a perceptual test rating (GRBAS scale), and stroboscopy. RESULTS: The procedures were completed successfully in all cases. An exceptional case of a small hemorrhagic polyp allowed treatment with the laser only. The postoperative stroboscopic findings, maximum phonation time, and perceptual test rating all showed significant improvement compared with the preoperative state. No adverse effects, such as scarring or reduction of the mucosal wave, were observed in the current series. CONCLUSIONS: KTP laser photocoagulation is a relatively simple and safe procedure for treating microvascular lesions of the vocal fold. It is not recommended for photocoagulation of hemorrhagic polyps or hematomas, because such lesions have little blood flow inside and thus photocoagulation is usually impossible or requires too much laser energy. However, photocoagulation of perimeter or feeding vessels of such disorders may facilitate the following procedure by avoiding unnecessary bleeding, as well as preventing recurrence of hemorrhagic lesions.

Adult↗

Epidermoid cysts of the vocal cords.

Fifty-three cases of intracordal epidermoid cysts diagnosed, treated and followed from 1972 to 1981 are presented. In the clinical evaluation, special attention must be paid to the type of dysphonia and morphology of the vocal cords at indirect laryngoscopy. The epidermoid cyst is not easily visualized and the examiner must take into account signs like "monochorditis," slight bulging, unilateral nodule and diminished or abolished vibrations of one of the cords at stroboscopy. Microsurgical excision followed by voice therapy is the recommended treatment. The pathogenesis of these cysts is still speculative. Two theories are discussed: the traumatic theory and the dysembryoplastic theory.

Adolescent↗

Selection of video cameras for stroboscopic videolaryngoscopy.

Stroboscopic evaluation for the analysis of laryngeal function and disease has been reemphasized recently and its routine clinical use recommended. Many have found, however, that it is not always possible to obtain consistently satisfactory video images of stroboscopic laryngoscopy. The problem is related to the low intensity of the xenon light source during stroboscopy. The authors have tried many different video cameras available, along with the Brüel & Kjaer Rhino-Larynx Stroboscope type 4914, and two types of endoscopes (flexible and rigid). The cameras included 1) single tube camera, 2) single chip metal oxide semiconductors (MOS) solid-state camera, 3) single chip charge-coupled devices (CCD) solid-state camera, 4) three-tube camera, and 5) three-chip CCD camera. Currently available video cameras and their adaptability for stroboscopic videolaryngoscopy are discussed.

Equipment Design↗

Complications of laser surgery for recurrent respiratory papillomatosis.

During an 8-year period, 66 patients with recurrent respiratory papillomatosis underwent 890 laser microlaryngoscopy procedures. A retrospective analysis of immediate and delayed complications occurring with laser microlaryngoscopy in the treatment of these patients revealed that complications secondary to anesthetic technique and laser methodology were remarkably low (0.3%). Delayed complications of tissue injury (36% of pediatric patients and 17% of adult patients) were more frequent and included anterior glottic webbing, interarytenoid scarring and arytenoid fixation, vocal fold fibrosis, and generalized endolaryngeal glottic stenosis. All patients were evaluated by direct visualization and recording at the time of the operative procedure, as well as by review of intraoperative photographs. A smaller group of patients underwent analysis of voice recordings and laryngeal stroboscopy. The frequency and severity of tissue injury was higher in the patients with more severe disease who underwent multiple operative procedures.

Adolescent↗

Strobovideolaryngoscopy: results and clinical value.

Strobovideolaryngoscopy is a valuable addition to the diagnostic armamentarium because it allows the otolaryngologist to perform a detailed physical examination of the vibratory margin of the vocal fold. From 1985 through 1989, we performed 1,876 strobovideolaryngoscopy procedures, the majority on professional voice users. Previously, we reported findings on our first 486 strobovideolaryngoscopy procedures. Stroboscopic information influenced diagnosis or treatment in approximately one third. The present study was undertaken to determine whether additional experience had altered the clinical usefulness of the procedure. Diagnoses were noted before and after stroboscopy prospectively for 377 strobovideolaryngoscopy procedures performed during the calendar year 1989. In 53% of the procedures, strobovideolaryngoscopy resulted in no change in diagnosis. In 29%, preprocedure impressions were confirmed and additional diagnoses were made. In 18%, preprocedure diagnoses were found to be incorrect. The procedure has proven very helpful in caring for voice patients, modifying diagnoses in 47%, and confirming uncertain diagnoses in many of the other patients studied.

Humans↗

Physiologic assessment of arytenoid adduction.

Arytenoid adduction as described by Isshiki is a surgical technique used to improve vocal quality by adducting the arytenoid cartilage of a paralyzed vocal fold, medializing the fold, and closing the posterior glottic aperture. Surgical results of this operation were evaluated by preoperative and postoperative voice recordings, laryngoscopy, and stroboscopy. Objective measurements of vocal jitter, shimmer, and signal to noise ratio were done to assess changes in the vibratory patterns, and analysis of data from 12 patients revealed improved glottic function postoperatively. Often an anterior medialization procedure, primarily a type I thyroplasty, was used to supplement the posterior medialization achieved by adduction of the arytenoid. Arytenoid adduction is recommended as an effective and reliable treatment for posterior glottic insufficiency.

Adult↗

Videostroboscopy of human vocal fold paralysis.

Previous stroboscopic studies of human vocal cord paralysis have been infrequent and have lacked documentation of the site of lesion. In order to study human laryngeal paralysis, the recurrent and superior laryngeal nerves were infiltrated unilaterally with lidocaine hydrochloride in three human volunteers. Vagal paralysis was simulated by combined (superior and recurrent) infiltration in one volunteer. Additionally, 20 patients with untreated laryngeal paralysis were studied from the voice laboratory at UCLA. In addition to videostroboscopic analysis, photoglottography and electroglottography were performed and synchronized with the stroboscopic images. The most significant finding in stroboscopy of the paralyzed larynx was the asymmetry of traveling wave motion. The traveling wave on the normal vocal fold had a faster wave velocity that created a phase difference in the vibration of the two folds. The wave also traversed a greater distance along the vocal fold mucosa on the normal side. No patient or volunteer with untreated laryngeal paralysis had a symmetric traveling wave, either in superior or recurrent laryngeal nerve paralysis. Synchronization with glottography indicated that the differentiated electroglottographic waveform provides useful information about the timing of glottic opening and closure in states of asymmetric laryngeal vibration. Implications for future studies and for the diagnosis of laryngeal paralysis are discussed.

Adult↗