Vocal Fold Injection: Review of Indications, Techniques, and Materials for Augmentation

Vocal fold injection is a procedure that has over a 100 year history but was rarely done as short as 20 years ago. A renaissance has occurred with respect to vocal fold injection due to new technologies (visualization and materials) and new injection approaches. Awake, un-sedated vocal fold injection offers many distinct advantages for the treatment of glottal insufficiency (vocal fold paralysis, vocal fold paresis, vocal fold atrophy and vocal fold scar). A review of materials available and different vocal fold injection approaches is performed. A comparison of vocal fold injection to laryngeal framework surgery is also undertaken. With proper patient and material selection, vocal fold injection now plays a major role in the treatment of many patients with dysphonia

Stem cell approaches for vocal fold regeneration

OBJECTIVES/HYPOTHESIS Current interventions in the management of vocal fold (VF) dysfunction focus on conservative and surgical approaches. However, the complex structure and precise biomechanical properties of the human VF mean that these strategies have their limitations in clinical practice and in some cases offer inadequate levels of success. Regenerative medicine is an exciting development in this field and has the potential to further enhance VF recovery beyond conventional treatments. Our aim in this review is to discuss advances in the field of regenerative medicine; that is, advances in the process of replacing, engineering, or regenerating the VF through utilization of stem cells, with the intention of restoring normal VF structure and function. DATA SOURCES: English literature (1946–2015) review. METHODS We conducted a systematic review of MEDLINE for cases and studies of VF tissue engineering utilizing stem cells. Results The three main approaches by which regenerative medicine is currently applied to VF regeneration include cell therapy, scaffold development, and utilization of growth factors. CONCLUSIONS Exciting advances have been made in stem cell biology in recent years, including use of induced pluripotent stem cells. We expect such advances to be translated into the field in the forthcoming years. Laryngoscope, 126:1865–1870, 201

Viscoelastic and histologic properties in scarred rabbit vocal folds after mesenchymal stem cell injection

Objective/Hypothesis: The aim of this study was to analyze the short-term viscoelastic and histologic properties of scarred rabbit vocal folds after injection of human mesenchymal stem cells (MSC) as well as the degree of MSC survival. Because MSCs are anti-inflammatory and regenerate mesenchymal tissues, can MSC injection reduce vocal fold scarring after injury? Study Design: Twelve vocal folds from 10 New Zealand rabbits were scarred by a localized resection and injected with human MSC or saline. Eight vocal folds were left as controls. Material and Methods. After 4 weeks, 10 larynges were stained for histology and evaluation of the lamina propria thickness. Collagen type I content was analyzed from six rabbits. MSC survival was analyzed by fluorescent in situ hybridization staining from three rabbits. Viscoelasticity for 10 vocal folds was analyzed in a parallel-plate rheometer. Results: The rheometry on fresh-frozen samples showed decreased dynamic viscosity and lower elastic modulus (P < .01) in the scarred samples injected with MSC as compared with the untreated scarred group. Normal controls had lower dynamic viscosity and elastic modulus as compared with the scarred untreated and treated vocal folds (P < .01). Histologic analysis showed a higher content of collagen type 1 in the scarred samples as compared with the normal vocal folds and with the scarred folds treated with MSC. MSCs remained in all samples analyzed. Conclusions. The treated scarred vocal folds showed persistent MSC. Injection of scarred rabbit vocal folds with MSC rendered improved viscoelastic parameters and less signs of scarring expressed as collagen content in comparison to the untreated scarred vocal folds

The voice and laryngeal dysfunction in stroke: A report from the Neurolaryngology Subcommittee of the American Academy of Otolaryngology-Head and Neck Surgery

Stroke is the third leading cause of death in the United States, behind heart disease and cancer. It affects as many as 5% of the population over 65 years old, and this number is growing annually due to the aging population. A significant portion of stroke patients that initially survive are faced with the risk of aspiration, as well as quality-of-life issues relating to impaired communication. The goal of this paper is to define the scope of practice in otolaryngology for these patients, and to review pertinent background literature. Consensus report and retrospective literature review. Otolaryngology involvement in these patients is critical to their rehabilitation, which often requires an interdisciplinary team of specialists. This committee presentation explores epidemiological data regarding the impact of stroke and its complications on hospitalizations. A pertinent review of neuroanatomy as it relates to laryngeal function is also discussed. State-of-the-art diagnostic and therapeutic procedures are presented. There is a well-defined set of diagnostic and therapeutic options for laryngeal dysfunction in the stroke patient. Otolaryngologists play a critical role in the interdisciplinary rehabilitation team