Search PubMed⌕ Search

Biomedical subjects

Steven M Zeitels

Publications and source records attributed to Steven M Zeitels.

At least 37 records · Page 2Linked to original sources
PubMed2005

A new instrument for intraoperative assessment of individual vocal folds.

OBJECTIVES: Intraoperative assessment of vocal fold vibration during phonomicrosurgery performed under general anesthesia may enhance surgical decision-making. We therefore developed and bench-tested a new device we refer to as the aerodynamic vocal fold driver (AVFD). MATERIALS AND METHODS: The AVFD comprises a hand-held probe that uses airflow to drive individual vocal folds into phonatory-like vibration. This permits stroboscopic visualization of mucosal waves with simultaneous control of subglottal air pressure. In initial experiments to validate the technique, AVFD driven phonation and conventional whole-larynx phonation were compared using excised canine larynges (n = 14). RESULTS: Single vocal fold phonation using the AVFD and whole larynx phonation yielded similar, positive correlations between subglottal pressure and both amplitude and frequency of vibration. Experiments simulating vocal fold scar-related mucosal stiffening by subepithelial injection of fixative showed the expected elevation of phonation threshold pressures as measured with the AVFD. Likewise, unilateral tissue compression injury disrupted vocal fold vibration, and the AVFD was useful for quantifying improvement in the damaged vocal fold after repair with injection of cross-linked hyaluronic acid gel. CONCLUSIONS: These results show that this new instrument has the potential to provide novel and useful information for laryngeal experimentation and to improve phonosurgery.

Air↗
PubMed2005

Midmembranous vocal fold lamina propria proteoglycans across selected species.

OBJECTIVES: We examined the proteoglycan (PG) and associated sulfated glycosaminoglycan (GAG) content of the midmembranous vocal fold lamina propria (LP) of humans, dogs, pigs, and ferrets. METHODS: The LP PG levels were assessed indirectly by quantifying the associated sulfated GAGs, and immunohistochemical analyses of specific PGs and/or GAGs (PGs/GAGs) were conducted. RESULTS: Sulfated GAGs constituted approximately (average +/- SEM) 14.7 +/- 2.1 microg per milligram of tissue total protein in the human LP--similar to levels in canine, porcine, and ferret LPs (p > .05). Immunohistochemical analysis identified versican, chondroitin 4- and 6-sulfate, and heparan sulfate in the LP extracellular matrix--PGs/GAGs previously believed to be localized only intracellularly and in the basement membrane. Observations of PG/GAG staining patterns resulted in identification of microstructurally based subdivisions of canine, porcine, and ferret LPs. CONCLUSIONS: The sulfated GAG concentration in human LP was similar to that of dermis. In contrast to the interspecies similarity in LP sulfated GAG levels, immunohistochemical analysis indicated notable interspecies differences in specific PG/GAG distributions. Moreover, spatial variations in the presence of several PGs/GAGs were observed--variations that may be integral in maintaining normal LP physiology. Finally, the noted canine, porcine, and ferret LP subdivisions may yield insight into the adaptation of LP microstructure to the phonatory needs of each species.

Adult↗
PubMed2005

Imaging the mucosa of the human vocal fold with optical coherence tomography.

OBJECTIVES: Discerning the layered microstructure of the vocal folds is critical for effective phonomicrosurgery. Optical coherence tomography (OCT), a noncontact, noninvasive technology that provides cross-sectional images by means of backscattered light, offers the potential for delineating these layers in vivo. METHODS: The glottal mucosa of 3 human cadaver larynges was imaged with conventional OCT and polarization-sensitive OCT (PS-OCT). Images were obtained through the epithelium and lamina propria. RESULTS: Although the superficial layer of the lamina propria appeared quite homogeneous, the outer surface of the superficial lamina propria was correlated with an increase in backscatter with OCT. The superficial lamina propria and vocal ligament were correlated with a marked increase in tissue birefringence with PS-OCT. CONCLUSIONS: This preliminary study demonstrates the capacity of OCT and PS-OCT for visualizing the layered microstructure of the vocal fold mucosa. We believe that these imaging techniques will have applications in the exploration of solutions to vocal fold scarring and in imaging vocal fold disorders in the clinic and operating room.

Cadaver↗
PubMed2004

Pediatric video laryngo-stroboscopy.

OBJECTIVE: Laryngo-stroboscopy remains as the clinical gold standard for assessing properties of the glottal phonatory and valvular function. This includes deficits of closure as well as mucosal wave irregularities secondary to abnormal zones of pliability and symmetry. Per-oral stroboscopy has technical limitations in children due to the size of the telescope and issues of patient compliance. However, flexible laryngoscopy is readily performed in newborns and young children. This paper describes the use of a new trans-nasal, digital flexible laryngoscope, which allows for laryngo-stroboscopy in children. METHODS AND RESULTS: A prospective longitudinal series was done on 25 children ages 19 months-13 years (mean age, 7.0 years) with this new technology. All 25 were successfully examined. CONCLUSIONS: New technological advancements in the design of digital flexible endoscopes has allowed for laryngo-stroboscopy, and therefore, provides the potential for expanding the population of children with vocal disorders in whom stroboscopic imaging is possible. Larger studies will be necessary to determine its limitations related to age, development, and disease. As the study of pediatric voice disorders continues to evolve, accurate diagnosis is essential to apply state of the art non-operative and phonosurgical interventions. Further longitudinal studies are currently underway to continue to refine techniques of pediatric voice assessment and to define limitations of this new technology.

Adolescent↗
PubMed2004

Optimizing voice after endoscopic partial laryngectomy.

Phonosurgical management of early and midsized glottic cancer has evolved considerably during the past decade. There has been a partial migration from transcervical to transoral partial laryngectomy to diminish perioperative morbidity (ie, tracheotomy) and to facilitate subsequent voice restoration. After an endoscopic partial laryngectomy heals, a medialization of the glottal neocord should be done. An endolaryngeal injection or transcervical medialization is used to reconstruct the glottal valve and the associated aerodynamic competency, which ultimately enhance voice quality. These reconstructive techniques will improve the voice outcome subsequent to almost any endoscopic vertical partial laryngectomy; however,a near-normal conversational level voice can be achieved inpatients in whom there is one remaining normal vocal fold. These favorable results are based on the fact that after effective glottal closure is achieved through the reconstruction, the primary oscillator is the layered microstructure of noncancerous glottal tissue.

Endoscopy↗
PubMed2004

Technique of en block laser endoscopic frontolateral laryngectomy for glottic cancer.

During the last 30 years, there has been expansion of the role of endoscopic partial laryngectomy procedures since Jako, Strong, and Vaughan explored the possibilities of CO2 laser microlaryngeal procedures. Despite the fact that a number of investigators have verified the validity of endolaryngeal laser resection of mid-sized glottic cancer, there are many who are unfamiliar with the technique and others who are uncomfortable with sectioning the tumor to facilitate its resection. In the past 3 years, 15 patients underwent successful en block resection of mid-sized glottic cancer (T1b 2, T2b 11, T3 2). Because en block resection is more consistent with open oncologic approaches, this method should widen the acceptance of this approach in selected lesions. The nuances of en block endoscopic frontolateral laryngectomy are presented with the hope that more surgeons will adopt this philosophy as an aspect of their armamentarium.

Glottis↗
PubMed2004

A laryngeal dissection station: educational paradigms in phonosurgery.

OBJECTIVES: To introduce a new tool for phonosurgical training and education. A multitude of innovations in complex laryngeal surgery has catalyzed new educational initiatives. Establishing dexterity in phonomicrosurgery is often difficult to achieve while working on patients because of the narrow margin for success. Furthermore, laryngoplastic phonosurgery and open partial laryngectomy require sophisticated knowledge of precise anatomic relationships, which can be difficult to express in images. Finally, many teaching programs do not have a high volume of these procedures, and there is a significant need to transmit this information in continuing education courses. STUDY DESIGN: Prototype design. METHODS: A laryngeal dissection station (LDS) was designed to facilitate the acquisition of high-level procedural skill sets for both transoral and transcervical techniques. RESULTS: This LDS can be used in existing temporal-bone laboratories by using cadaveric larynges. A rectangular frame supports two adjustable holders, one for the larynx and one for the examining speculum of a laryngoscope. Procedures are performed with the larynx fixed in space by a novel fixator. Variation in position and orientation of the components affords simulation of both microlaryngoscopy and open surgery. The dissection station can accommodate virtually any laryngoscope, regardless of size or shape. CONCLUSIONS: This training apparatus should facilitate laryngeal surgical instruction in residency training and continuing medical education. This device and others like it can help establish clinical competency in laryngology, should this become necessary in future educational models of residency training and recertification.

General Surgery↗
PubMed2004

Suspension laryngoscopy revisited.

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

History, 19th Century↗
PubMed2004

Office-based treatment of glottal dysplasia and papillomatosis with the 585-nm pulsed dye laser and local anesthesia.

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

Adult↗
PubMed2004

Surface electromyographic activity in total laryngectomy patients following laryngeal nerve transfer to neck strap muscles.

Hands-free triggering and pitch control would improve electrolarynx devices, which are inconvenient to use and sound unnatural. The present study tested the strategy of salvaging voice-related neural signals for hands-free electrolarynx control either by transferring cut recurrent laryngeal nerves (RLNs) to denervated neck strap muscles or by preserving strap muscles with their normal innervation. An RLN nerve transfer was performed at the time of total laryngectomy in 8 individuals, and in 5 of these subjects, strap muscles with intact ansa cervicalis innervation were also preserved for comparison. Neck surface electromyography performed over the strap muscles was used periodically for more than 1 year on phonatory and nonphonatory tasks. Signals were eventually obtained in all subjects from both RLN-innervated and ansa-innervated strap muscles that correlated with speech production. After 1 year, RLN-driven signals were larger than ansa-driven signals in magnitude, and their timing appeared better correlated with intended phonation. The results show that neck surface electromyography is an effective control source for hands-free electrolarynx activation, and that RLN transfer may provide the best approach for obtaining phonation-related activity.

Electromyography↗
PubMed2004

Adduction arytenopexy for vocal fold paralysis: indications and technique.

Adduction arytenopexy was designed as an innovation to arytenoid adduction, however the pragmatic issues regarding patient selection for these procedures has not been comprehensively assessed. A prospective examination was performed on 100 consecutive patients who had undergone laryngoplastic phonosurgical reconstruction for paralytic dysphonia. Seventy-seven of 100 (77 per cent) were judged pre-operatively to gain potentially significant phonatory enhancement from an arytenoid procedure. Fifty-six of 77 (73 per cent) underwent adduction arytenopexy; 17 of 77 (22 per cent) were judged pre-operatively to have inadequate respiratory abduction of the contralateral arytenoid and two out of 77 (three per cent) had athletic aerodynamic requirements. In another two out of 77 (three per cent), there was a chance of favourable reinnervation and thus it was not the preferred method. The majority of patients were judged pre-operatively to gain potentially substantial phonatory enhancement from an arytenoid procedure. However, in this series, approximately 25 per cent of the patients were considered to be unsuitable candidates for an arytenoid medializing procedure, primarily because it was deemed that the operation could result in an inadequate airway.

Arytenoid Cartilage↗
PubMed2003

Medialization laryngoplasty with Gore-Tex for voice restoration secondary to glottal incompetence: indications and observations.

Gore-Tex has been used as an effective implant for medialization laryngoplasty in the management of paralytic dysphonia; however, reporting of large patient cohorts has been limited. Furthermore, the use of Gore-Tex in the treatment of glottal incompetence secondary to soft tissue defects has not yet been described. Finally, a number of the procedural nuances of using Gore-Tex have not been elucidated. A prospective investigation was done on 142 patients who underwent 152 Gore-Tex medialization laryngoplasties in 183 vocal folds from December 1997 to March 2002. The primary diagnoses prompting the 152 procedures were paralysis in 94, paresis in 18, cancer reconstruction in 14, sulcus vocalis in 6, atrophy in 3, trauma defect in 5, arytenoid dislocation in 3, bilateral paralysis in 3, bilateral paresis in 1, parkinsonism in 4, and neurologic aerodynamic dissociation in 1. One patient who underwent reconstruction of a complex cancer defect required endoscopic removal of the Gore-Tex because of persistent granulation. Clinical observations reveal that Gore-Tex is a versatile implant that is ideally suited for phonosurgical reconstruction of aerodynamic glottal incompetence secondary to a variety of causes. Gore-Tex was especially useful for medialization of complex anatomic soft tissue defects such as those resulting from cancer resection, trauma, atrophy, and sulcus vocalis. There was superior ease in handling, placement, and in vivo adjustability.

Adult↗
PubMed2003

585-nm pulsed dye laser treatment of glottal dysplasia.

Management of glottal dysplasia can be difficult and often results in a suboptimal treatment outcome. The surgeon and patient must cooperatively balance decisions regarding the effects of possible malignancy, vocal dysfunction, and recurrences leading to multiple use of general anesthetics. A pilot study was done in 57 cases (36 patients and 97 vocal folds) without complication to evaluate the effectiveness of a 585-nm pulsed dye laser (PDL; 450-micros pulse width, 19 to 76-J/cm2 fluence, 1- to 2-mm spot size) in the treatment of vocal fold keratosis. Forty of the 57 cases had bilateral treatment. Phonomicrosurgical resection was done in 35 of the 57 cases after PDL treatment. Of this group, 10 cases were found to have hyperplasia, 21 dysplasia, 4 carcinoma in situ, and 1 carcinoma. One patient had phonomicrosurgical resection before PDL treatment. In 21 of the 57 cases, the disease was irradiated without resection (4 unilateral lesions and 17 bilateral lesions). Approximately 80% of the patients in this series had a greater than 70% reduction in the size of the lesion with the use of the PDL irrespective of whether they underwent resection. Clinical observation revealed no new anterior commissure web formation despite bilateral anterior commissure treatment in 28 of the 57 cases. The PDL enhanced the epithelial excision by improving hemostasis and by creating an optimal dissection plane between the basement membrane and the underlying superficial lamina propria. In this initial trial, the PDL provided relatively safe and effective treatment for glottal dysplasia. Analysis of patterns of recurrence will require longer follow-up.

Adult↗
PubMed2002

Management of common voice problems: Committee report.

OBJECTIVE: This report provides the reader with a state-of-the-art update on a number of common voice problems that require phonosurgical intervention. STUDY DESIGN AND SETTING: This multiauthor review is not a position statement of the American Academy of Otolaryngology-Head and Neck Surgery (AAOHNS) and may reflect institutional preference and/or bias. It arose from a panel discussion at the AAOHNS meeting in 2000. RESULTS: We provide a review of the genesis and management of papillomatosis, dysplastic glottal epithelium, arytenoid granulomas, Reinke's edema, and vocal-fold paralysis. CONCLUSIONS AND SIGNIFICANCE: In the past decade, there has been a dramatic expansion of knowledge regarding a variety of voice disorders and associated treatment. There has been a convergence of basic science investigations in anatomy, physiology, and pathology with clinical trials of treatment, both surgical and nonsurgical. This information should provide the reader with current insight into critical management issues of the aforementioned disorders.

Arytenoid Cartilage↗