Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “Stroboscopy”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 127 records · Page 7Linked to original sources

[Laryngeal immobility after thyroidectomy].

One of the most common complications of surgery of the thyroid gland is vocal folds immobility. New advances in its management have been achieved over the last few years. Laryngeal electromyography, stroboscopy, and computerized analysis of the voice help guide diagnosis, allowing differentiation between recurrent nerve paralysis and glottis traumatism due to intubation, and further follow-up of recovery with relevant therapeutic decisions. In case of unilateral vocal fold paralysis, intrafold silicone or injection of autologous fat is more and more routinely used to obtain vocal rehabilitation. In case of bilateral vocal fold paralysis, to avoid tracheotomy, partial posterior cordectomy using laser surgery restores sufficient laryngeal airflow, with minimal vocal sequelae. Early management of these complications by teams of specialists should allow appropriate and less invasive surgery.

Aged↗

Instability of voice in adolescence: pathologic condition or normal developmental variation?

OBJECTIVE: Pediatricians often send adolescents with dysphonia to the otorhinolaryngologist's office to find the reason for their hoarseness. The aim of this study was to identify the main characteristics of adolescent voice and to determine which characteristic (variable of voice analysis) can distinguish normal variations of voice development from pathologic disorders. STUDY DESIGN: On the basis of history, indirect laryngoscopy, and stroboscopy, 51 adolescents (22 boys, 29 girls) from age 10 to 17 years were divided into four subgroups: candidates for singing lessons without voice problems, subjects with mutation voice disorders, subjects with functional dysphonia, and subjects with vocal cord nodules. Voice analysis by Multi-Dimensional Voice Program (Kay Elemetrics) evaluated the fundamental frequency, the variability of pitch and amplitude (loudness), and the presence of noise in the analyzed voice sample of each of the subjects. Data were analyzed with the SPSS+/PC Statistical Program. RESULTS: All mean values of variables that describe variability of pitch and amplitude were abnormal in boys and in girls, with greater abnormality among boys. The variability of loudness and specifically the variability of pitch were abnormal in a majority of subjects. A significant negative correlation between age and fundamental frequency was stated in boys only and between age and variability of amplitude in girls only. Variables that express variability of pitch and amplitude correlated positively between themselves. No significant differences were found between the first subgroup (candidates for singing lessons), which represented a normal population, and the other three subgroups (subjects with mutational disorders, functional dysphonia, and vocal cord nodules). In addition, no significant differences were found between the first three subgroups (subjects without voice problems and subjects with functional voice disorders) and the fourth subgroup (subjects with vocal cord nodules: organic lesion of laryngeal mucosa). CONCLUSIONS: According to this study, the main characteristic of adolescent voice is the instability of amplitude (loudness) and specifically the instability of pitch. Female voices appear more stable than male voices. No single variable of performed voice analysis can distinguish normal variation of voice development from pathologic disorders. The reason for this instability can be attributed to more gradual adaptation of the afferent and efferent nervous control to the rapid growth of the phonatory, respiratory, and resonatory organs. In the growing speech apparatus, optimal phonatory patterns can be created; therefore adolescence is an ideal period for treatment of functional voice disorders.

Adolescent↗

Electromyography and the immobile vocal fold.

Laryngeal EMG has become a useful tool for the otolaryngologist in the four decades since the pioneering work of Faaborg-Anderson and Buchtal. It is able to distinguish between mechanical limitation and denervation in an immobile vocal fold. In the paralyzed vocal fold, it can guide workup by pointing to the site of the lesion. In the hands of a circumspect clinician, it can provide clinically valuable information regarding prognosis. Useful application of laryngeal EMG must rest on the basic fact that it isa qualitative test. Because of factors like sampling error, interfering signal from neighboring muscles, difficulties in needle placement, and our in-complete understanding of reinnervation physiology, the boundary between sophisticated, subtle interpretation and overreading is particularly difficult to distinguish. EMG diagnosis is based on patterns of abnormalities over time and, like other tests, requires interpretation in a clinical context. As in any such undertaking, there is no substitute for good judgment and experience. The most important benefit of clinical use of laryngeal EMG may be that it has catalyzed and broadened interest in laryngeal neurophysiology in the same way that stroboscopy has focused attention on the structure and function of the vocal fold lamina propria. The continuing refinement of electrodiagnostic approaches to the larynx that has resulted, including quantitative, single-fiber. and vector laryngeal EMG, and evolving methods of nerve conduction testing will continue to yield important insights into mechanisms of neural control that are likely to drive developments in the treatment of vocal fold paralysis in the future.

Action Potentials↗

The superior laryngeal nerve: function and dysfunction.

Despite long-standing clinical interest in SLN dysfunction, most aspects of this entity continue to require clarification. The replacement of the laryngeal mirror by flexible fiberoptic and rigid rod-lens laryngoscopy (including stroboscopy) and the resulting improvement in laryngeal visualization and documentation of examination has not resulted in a better definition of characteristic signs. Symptoms are often vague, and most are shared with other voice disorders. Under the circumstances, there is good reason to suppose that SLN dysfunction yields a clinical picture at least as heterogeneous as recurrent laryngeal nerve injury and a good deal more subtle. Faced with significant inconsistencies in clinical presentation, the clinician is hard-pressed to draw conclusions regarding prevalence, patterns of dysfunction, natural history, treatment, and even about its overall significance. EMG. used judiciously and complemented by frequency range testing, seems to hold more promise as a means of reliable diagnosis than laryngoscopic examination and may serve to resolve some of the confusion surrounding SLN dysfunction. It is equally important that the otolaryngologist guard against falling into the easy habit of attributing vocal disturbance that cannot be otherwise explained to SLN dysfunction in the absence of EMG evidence. If ambiguities surrounding SLN paralysis and paresis are to be clarified, diagnostic rigor is essential.

Chemoreceptor Cells↗

Perceptual and laboratory assessment of dysphonia.

The voice laboratory is an essential tool in the voice clinic. It provides a functional diagnosis of disturbed voice production, demonstrating the deviant characteristics, limitations, and possibilities for change. As voice is multidimensional, several aspects need to be documented, quantified, and analyzed: perception, stroboscopy, aerodynamics, acoustics, self-evaluation by the patient, and in specific cases, physiologic signals, such as electroglottography, flow glottography, nasometry, and electromyography. Effectiveness and outcome studies rely on such data.

Electromyography↗

Voice disorders in children.

Pediatric patients with voice or speech problems usually should receive a team assessment in which communication between the pediatrician or primary care physician, the otolaryngologist, and speech pathologist occurs. Although speech or voice problems may prompt an otolaryngologic evaluation, the voice or speech problem simply may be the manifestation or symptom of a larger or more complex disease process. Whether that is the case of hypernasal speech, eventually leading to the diagnosis of velocardiofacial syndrome, or bilateral vocal fold paralysis, eventually leading to the diagnosis of hydrocephalus, it is apparent that patients with speech or voice disorders may eventually require multidisciplinary evaluation. The outlook for children with speech and voice difficulties is better than ever. Recent equipment advances, such as flexible laryngoscopy, video stroboscopy, and nasometry, for detection, evaluation, and management of speech problems have created a better environment than ever existed for care of these problems. Much research is being performed in the area of pediatric voice and speech problems. The National Institute of Deafness and Communicative Disorders and the National Institute of Dental Research have funded and currently fund many projects in these areas. Many pediatric hospitals now have voice or speech disorder clinics in which multiple disciplines are brought together to evaluate children with these problems. Children benefit best when speech and voice problems are managed in an interdisciplinary setting when necessary and by professionals who have experience and training in these specialized pediatric problems. Given the local, professional, and national resources that are expended toward recognition and treatment of speech disorders in children, it is truly a tragedy when those resources cannot be brought to assist children with voice and speech problems. Although voice and speech problems usually are recognized by parents or concerned family members, this task may rest on the pediatrician or other primary caregiver.

Child↗

Management of vagus nerve injury afer carotid endarterectomy.

BACKGROUND: Inadvertent injury to the vagus nerve or its branches during carotid endarterectomy can result in adductor vocal cord paralysis (hoarseness) and cricopharyngeal dysfunction (dysphagia) with aspiration, known as "double trouble." This study describes our experience in the management of this complication in cases where conservative treatment failed. METHODS: All patients were examined by a vascular surgeon, a head and neck surgeon, and a speech therapist. Their examinations included comprehensive speech evaluation, video stroboscopy, video fluoroscopy, and methylene blue testing for aspiration. All patients underwent Teflon injections to medialize the paralyzed vocal cord and a cricopharyngeal myotomy to restore swallowing and alleviate aspiration. RESULTS: Fourteen patients, eight men and six women, were treated. The duration of dysfunction was 24 weeks in two patients, 6 weeks in four patients, 4 weeks in three patients, and 1 week in five patients. Five patients had severe dysfunction (defined as difficulty in swallowing both solid and liquid foods with more than 20% aspiration), seven patients had moderate dysfunction (defined as difficulty swallowing solid food with aspiration of less than 20%), and two patients had mild dysfunction (defined as difficulty in swallowing solids but with no aspirations). After the Teflon injections and myotomy, 13 of 14 patients had satisfactory outcomes, including normal voice and swallowing. CONCLUSIONS: Vagus nerve injury from a carotid endarterectomy can be a debilitating complication. Prevention, early recognition, and prompt correction of these injuries are important in the management of this complication.

Aged↗

Voice problems in children: pathogenesis and diagnosis.

Voice problems seem to concern more than one child out of twenty, and may concern quality (hoarseness), resonance (nasality), pitch (mutation) and loudness. The main etiological categories are defined as organic (congenital/acquired), functional/habitual (especially due to voice abuse and misuse), and psychogenic (especially mutation disorders). Flexible transnasal endoscopes of small diameter (2.3 mm) are optimally suited for accurate endoscopic diagnosis, especially if combined with video-recording and stroboscopy.

Child↗

Strobophotoglottographic transillumination as a method for the analysis of vocal fold vibration patterns.

The purpose of this exploratory study was to determine if laryngeal transillumination in combination with stroboscopy (strobophotoglottography; SPGG) is useful for (1) the visualization of vocal fold vibration (VFV) opening patterns, (2) the localization of initial vocal fold opening in horizontal glottal thirds (anterior, midmembranous, and posterior), (3) determination of the temporal correspondence of the so-called electroglottography (EGG)-knee and initial vocal fold separation, and, finally, (4) automatized quantitative measurements of glottal area function within endoscopic images. With stroboscopic transillumination, initial inferior vocal fold separation was detectable during the "closed" phase, where the vocal folds were still closed in the upper portion and therefore initial inferior vocal fold separation could not be visualized with usual laryngoscopy techniques. In the horizontal plane within similar fundamental frequencies in modal voice registers in two male subjects, localization of initial glottal opening depended on the voice types used (soft, normal, or pressed phonation). We found zipperlike posterior-to-anterior openings, initial midmembranous openings, initial anterior openings, as well as simultaneous initial opening of all three portions in the two healthy male adults examined. This technique proved to add temporal and spatial information to vocal fold opening patterns and extends our examination techniques to the very beginning of vocal fold opening at the inferior portion. Simultaneous electroglottogram tracking and comparison with bidirectionally illuminated stroboscopic images revealed a time-locked correspondence of the EGG-knee with the aforementioned initial inferior vocal fold separation. Bidirectional illumination combined with digital color extraction techniques allowed for image separation of subglottally and supraglottally illuminated structures. This facilitated vocal fold contour detection and automatized image processing, for example, for determination of glottal area function, and is considered to be a further step to objective automatized quantitative measurements within endoscopic images.

Adult↗

Phonomicrosurgical management of vocal fold polyps: the subepithelial microflap resection technique.

Vocal fold polyps are typically caused by acute and chronic trauma to the microvasculature of the superficial lamina propria (SLP). Shearing stresses that are induced by hyperfunctional glottal sound production lead to bleeding into the SLP and malformed neo-vascularized masses. Because the primary process does not involve the epithelium, the authors designed a technique to resect hemorrhagic polyps by epithelial cordotomy with partial or complete preservation of the vocal fold epithelium. This approach is different from the traditional microsurgical resection of hemorrhagic polyps by amputation with or without the carbon dioxide laser. Forty patients who underwent microlaryngoscopic resection of hemorrhagic polyps from 1996 through 1998 were reviewed retrospectively. Thirty-six of the 40 procedures were by epithelial cordotomy and subepithelial removal of the polyp contents. Sixteen of 36 were assisted by a subepithelial infusion of saline and epinephrine, and all were 3 mm to 6 mm. Four of 40 polyps were amputated; all of these were less than 3 mm and were pedicled on a narrow base. Cold instruments were used exclusively in all 40 patients. Postoperative laryngeal stroboscopy within 2 weeks revealed improved mucosal wave propagation and improved glottal closure in all 33 patients in whom postoperative strobovideolaryngoscopy was available. The epithelial cordotomy technique was introduced to minimize disturbance of normal SLP and epithelium. Despite the hemorrhagic nature of these lesions, cold instruments could be used exclusively with facility due to careful microdissection between the polyp and the residual normal SLP and the enhanced hemostasis provided by the subepithelial infusion of saline and epinephrine. The rapid return to improved glottal function is the result of this ultra tissue-sparing technique.

Adult↗

Bamboo node: primary vocal fold lesion as evidence of autoimmune disease.

Descriptions of vocal fold lesions related to autoimmune diseases are rare in the literature, and focus mainly on rheumatoid nodules. This is the first report in which autoimmune diseases were promptly suspected by the observation of a unique white transverse submucosal lesion in the vocal fold during clinical examination. This lesion, reported only in autoimmune disease, has been called the bamboo node and its features are different from those of rheumatoid nodules. We report here on two patients who did not have a diagnosis of systemic disease before investigation of their main complaint of hoarseness. At the patients' first visit, vocal fold bamboo nodes were seen in the vocal fold and the otolaryngologist suspected the presence of an autoimmune disease. We requested clinical investigation to clarify our suspicion that there was an underlying systemic disease. After the investigation, both patients were shown to have autoimmune disease, Sjögren's syndrome and systemic lupus erythematous, respectively. This paper emphasizes the important role of the otolaryngologist in the detection of these unique lesions in the vocal folds through the conventional laryngeal methods. These methods consisted of direct observation with a rigid laryngeal endoscope and investigation of the patient's distinctive vibratory pattern by means of laryngeal stroboscopy. The method of treatment we used to obtain the best outcome in terms of voice improvement is also discussed.

Adult↗

Lateral phase mucosal wave asymmetries in the clinical voice laboratory.

Anecdotally, in some persons it has been observed by the Senior Author (K.K.) that asymmetries of the mucosal wave exist when examined videostroboscopically. In the vast majority of these people, no pathology is ever discovered. Mucosal wave asymmetries could cause concern for the otolaryngologist, who may consider them to be a forewarning of subclinical pathology and subject the patient to unnecessary, expensive, and anxiety-provoking investigations or interventions. The purpose of this study was to establish the prevalence of mucosal wave asymmetries in an asymptomatic population lacking laryngeal pathology. Acoustic spectral analysis is also utilized to determine if the presence of subharmonics might be associated. A hospital-based, cross-sectional study design was used. The subjects had no known vocal or medical pathologies, and were nonsmoking. The study group was composed of 30 males aged 35-50 years and 30 women between 22-55 years. Each of the males underwent acoustic spectral analysis; and all subjects completed a medical questionnaire, subjective talkativeness rating, and videostroboscopic laryngeal examination. 10.5% of the subjects (exact 95% CI = 4.0-21.5%) exhibited mucosal wave variations at stroboscopy, characterized as periodic lateral phase asymmetries found consistently in both the modal and upper registers. There was no association with the chosen acoustic spectral parameters, talkativeness scales, or questionnaire-based variables. Mucosal wave asymmetries may be a variance of normal, and are likely to be far more common in the general population than previously believed. The prevalence detected here is expected to be important in the clinical laryngology practice, where these asymmetries may be frequently encountered and influencing management decisions. There has been little normative data published for variations of the mucosal wave specifically for epidemiological purposes. Clinically, in the absence of such data, otolaryngologists may over interpret videostroboscopic findings, leading to unnecessary investigations or interventions.

Adult↗

Strobovideolaryngoscopy in the management of acute laryngeal trauma.

Surgical intervention in the management of acute laryngeal trauma can sometimes pose a difficult decision. The objective of this study is to evaluate the effectiveness of strobovideolaryngoscopy (SVL) in determining the course of management for patients sustaining acute laryngeal trauma. A 20-year retrospective study of patients presenting with acute laryngeal trauma was performed in order to determine if the addition of SVL during the study period changed the management of certain acute laryngeal injuries. Patients sustaining blunt laryngeal trauma evaluated at our institution from 1981 to the present were reviewed. There were 40 patients identified that were grouped by severity according to the Schaefer classification. Analysis included mechanism of injury, clinical presentation, assessment, treatment, and outcome. Group 1 injuries were the most common, with motor vehicle accident (MVA) the most frequent mechanism of injury. Initial assessment included fiberoptic laryngoscopy and computed tomography (CT) imaging in all patients not requiring immediate exploration. SVL was used in 20 patients, with 7 undergoing stroboscopy within 24 hours of presentation. All 7 patients were managed conservatively without surgical intervention or the need to establish an alternative airway. SVL improves the clinical assessment of patients with acute laryngeal injury. This study supports its use and found it to be an important factor in determining the need for surgical intervention. SVL may also shorten the hospital stay in these patients.

Acute Disease↗

Arytenoid adduction and type I thyroplasty in the treatment of aphonia.

Arytenoid adduction is a procedure used to medialize the paralyzed vocal fold, closing the posterior glottis. Isshiki type I thyroplasty allows medialization of the anterior membranous vocal fold. Using the arytenoid adduction, in combination with Isshiki type I thyroplasty as needed, five patients were treated for aphonia. Surgical results were evaluated with voice recordings, electroglottography, and photoglottography. Jitter ratio, shimmer ratio, and signal-to-noise ratio were measured. Laryngeal stroboscopy and glottography were used to assess the mucosal wave and vibratory nature of the vocal folds. After operation, vocal function was restored. Analysis of data from these five aphonia patients revealed improved glottic phonatory function. The arytenoid adduction in combination with the Isshiki type I thyroplasty is an effective technique for aphonia caused by a significant posterior glottic gap with unilateral vocal-cord paralysis.

Arytenoid Cartilage↗

Episodic paroxysmal laryngospasm: voice and pulmonary function assessment and management.

Episodic paroxysmal laryngospasm (EPL) is a sign of laryngeal dysfunction, often without a specific organic etiology, which can masquerade as asthma, vocal fold paralysis, or a functional voice disorder. The intermittent respiratory distress of EPL may precipitate an apparent upper airway obstructive emergency, resulting in unnecessary endotracheal intubation, cardiopulmonary resuscitation, or tracheostomy. During 27 months, seven women and three men, age 30-76 years, were assessed by a high diagnostic index of suspicion, an intensive history including psychosocial factors, physical examination of the airways, provocative asthma testing, and swallowing studies. Videolaryngoscopy, stroboscopy, and pulmonary flow-volume loop testing were definitive. The classic appearance was paradoxic inspiratory adduction of the anterior vocal folds with a posterior diamond-shaped glottic gap. During an attack of stridor or wheezing, attenuation of the inspiratory flow rate as depicted by the flow-volume loop suggested partial extrathoracic upper airway obstruction. Swallowing evaluation by videolaryngoscopy and videosophagography may uncover gastroesophageal reflux disease. Hallmarks of management include patient and family education by observation of laryngoscopic videos, a specific speech therapy program, psychotherapy, and medical treatment of associated disorders. Electromyography may become a valuable future adjunct. Unlike laryngeal dystonia, patients with EPL do not benefit from botulinum toxin type A.

Adult↗

The membranous contact quotient: a new phonatory measure of glottal competence.

The membranous contact quotient (MCQ) is introduced as a measure of dynamic glottal competence. It is defined as the ratio of the membranous contact glottis (the anterior-posterior length of contact between the two membranous vocal folds) and the membranous vocal fold length. An elliptical approximation to the vocal fold contour during phonation was used to predict MCQ values as a function of vocal process gap (adduction), maximum glottal width, and membranous glottal length. MCQ is highly dependent on the vocal process gap and the maximum glottal width, but not on vocal fold length. Five excised larynges were used to obtain MCQ data for a wide range of vocal process gaps and maximum glottal widths. Predicted and measured MCQ values had a correlation of 0.93, with an average absolute difference of 9.6% (SD = 10.5%). The model is better at higher values of MCQ. The theory for MCQ is also expressed as a function of vocal process gap and subglottal pressure to suggest production control potential. The MCQ measure is obtainable with the use of stroboscopy and appears to be a potentially useful clinical measure.

Animals↗

The "singing-acting" child: the laryngologist's perspective--1995.

A survey of pediatric otolaryngologists about voice disorders in children suggests that approximately 1% of children examined were noted to have voice problems, and in only one fifth of these children (0.2%) were the voice problems related to professional use of the voice, such as singing. Direct flexible laryngoscopy was the sole method of examination for 80% of the children examined by these pediatric specialists. Voice therapy for 6 months was generally recommended (88%). The survey represents an estimated clinical experience of > 160,000 children per year, and it achieved a response rate of 40% of pediatric otolaryngologists (48/120). Results suggest that the use of video and stroboscopy for examination of the pediatric voice would enhance understanding and assure correct diagnosis and treatment.

Child↗

Transoral laryngeal surgery under flexible laryngovideostroboscopy.

Although direct microlaryngoscopic surgery is universally accepted as the standard procedure for endolaryngeal surgery, general anesthesia and direct laryngoscopy are necessary during the procedure. Suspended laryngeal position also impedes intraoperative functional monitoring. Transoral laryngeal surgery under indirect laryngeal mirror or telescope has the advantage of sparing general anesthesia and direct laryngoscopy, but lower precision, difficult manipulation, and a high patient cooperation requirement make the procedure of limited application. Trying to overcome the above shortcomings, transoral laryngeal surgery under flexible laryngovideostroboscopy (FLVS) is undertaken at our institute. The surgery is performed at an outpatient office under topical anesthesia, with the help of high-resolution fiberoptic stroboscopy, high-quality CCD videocamera, and monitor. From October, 1993 to March, 1996, 157 patients with selected laryngeal problems were operated upon using this technique, and 150 patients smoothly completed the procedure with satisfactory results. The technique is highly effective, especially for limited-manipulation, lower precision procedures and for patients who are not candidates for general anesthesia. With proper patient selection, this is a cost-effective surgery of low invasiveness and high applicability.

Adolescent↗