Faculty Bibliography

OBJECTIVE/HYPOTHESIS: Glucocorticoids (GCs) are commonly used in the treatment of laryngeal disorders despite the absence of clear guidelines regarding their use. We sought to assess clinical practice patterns regarding GC use for various vocal fold diseases and to ascertain factors underlying the selection of particular GCs for different vocal fold pathology. STUDY DESIGN: Prospective, survey. METHODS: A web-based 20-question survey querying clinical indications for GC use and other factors influencing decision making in GC administration was distributed to 5280 otolaryngologists via e-mail using a commercially available database. RESULTS: The overall response rate for the survey was 4% (212/5280). Of the respondents, 99% reported GCs to be valuable in their practice. Previous experience/results, familiarity, and use in practice (68%, 54%, and 37%, respectively) were the most commonly cited reasons for choosing a particular GC; pharmacokinetic profile and academic literature were infrequently cited reasons. Fifty-four percent of respondents were more likely to prescribe GCs for vocal performers compared with other patients. Additionally, most respondents stated that the potential for side effects only occasionally prevented GC utilization. CONCLUSIONS: GC prescription practices vary greatly among otolaryngologists. Drug choice appears to be driven primarily by clinician preference and personal experience rather than by specific pharmacologic or physiologic rationale. These findings likely reflect the current lack of well-constructed studies in the laryngology literature to guide GC selection and administration for benign disorders of the larynx and highlight an important potential area for future studies.

OBJECTIVES: We undertook to provide data regarding temporal measurements of swallow function obtained by dynamic magnetic resonance imaging in a midsagittal plane and to compare these values to normative fluoroscopy data. METHODS: Seventeen healthy female volunteers with no swallowing complaints underwent turbo-fast low-angle-shot magnetic resonance imaging with a 3-T scanner while swallowing liquid and pudding boluses delivered via syringe. Ninety sequential images were acquired with a temporal resolution of 113 ms per frame for each swallow. The imaging was performed in the midsagittal plane. The analyses focused on oral and pharyngeal transit times. RESULTS: All subjects tolerated the protocol without complaints or adverse events. The mean (+/- SD) oral transit times for liquids and pudding were measured as 0.25 +/- 0.09 second and 0.25 +/- 0.13 second, respectively. This difference was not statistically significant (p = 0.74). The mean pharyngeal transit times for liquids and pudding were measured as 0.84 +/- 0.16 second and 1.11 +/- 0.21 seconds, respectively. This difference achieved statistical significance (p < 0.0001). The intrarater and inter-rater reliabilities for the measurements were excellent. CONCLUSIONS: This sequence provided a high degree of temporal resolution of deglutition in the midsagittal plane. Furthermore, the temporal measurements acquired with dynamic magnetic resonance imaging were reliable and were relatively consistent with those of previous studies done with videofluoroscopy.

OBJECTIVES/HYPOTHESIS: To describe a novel conduction study of the laryngeal nerves, including normal values and abnormal findings. STUDY DESIGN: Prospective nonrandomized. METHODS: Seventeen healthy adult volunteers, as well as three patients with clinically identified laryngeal neuropathy, underwent low-level brief electrical stimulation of the laryngeal mucosa by means of a wire inserted via a transnasal flexible laryngoscope. Bilateral hookwire electrodes recorded the result in the laryngeal adductor muscles. RESULTS: This study yields an early response ipsilateral to the side of stimulation (LR1), which is uniform and consistent (right = 13.2 +/- 0.80 msec; left = 15.2 +/- 1.20 msec), and late bilateral responses (ipsilateral LR2 [LR2i] and contralateral LR2 [LR2c]), which exhibit greater variation in latency and morphology (right LR2i = 50.5 +/- 3.38 msec; left LR2i = 52.2 msec; right LR2c = 50.7 +/- 4.26; left LR2c = 50.6 +/- 4.07). Findings in abnormal patients differ significantly from normal, consistent with the distribution of neuropathy. CONCLUSIONS: We describe a novel, clinically applicable conduction study of laryngeal nerves. Normative electrodiagnostic values and variations of the reflex responses of the laryngeal adductor muscles in response to irritative stimulation of the laryngeal mucosa (Laryngeal Closure Reflex) are proposed. By enabling the determination of electrophysiological parameters of the superior laryngeal and recurrent laryngeal branches of cranial nerve X (CN X), this procedure, which is used as an adjunct to laryngeal electromyography, may provide earlier and more accurate information regarding the extent and grade of nerve injury. Because injury grade relates directly to prognosis, the information derived from this test may have clinical relevance in determining optimal treatment. LEVEL OF EVIDENCE: 4. Laryngoscope, 123:2202-2208, 2013.

OBJECTIVES/HYPOTHESIS: We hypothesize that the KTP laser has the potential to augment wound healing in a rat model, and this modality may serve as a therapeutic tool for the management of vocal fold fibrosis. STUDY DESIGN: Prospective, laboratory animal study. METHODS: Rats were subjected to either vocal fold injury +/- KTP laser treatment at low energy to simulate clinically relevant endpoints. In addition, cohorts were subjected to therapeutic KTP laser alone. Endpoints included the analyses of gene expression data related to the acute inflammatory response and extracellular matrix deposition and organization. RESULTS: Therapeutic KTP treatment was associated with an additive effect on inflammatory gene expression in the context of the injured rat vocal fold mucosa. A similar additive effect was observed for matrix metalloproteinase gene expression, similar to data previously reported in the dermatology literature. However, histologically, the KTP had little effect on established vocal fold fibrosis. CONCLUSIONS: These data are the first to attempt to provide mechanistic insight into the clinical utility of angiolytic lasers for vocal fold scar. Similar to previous data obtained in the skin, it appears that these effects are mediated by MMPs. LEVEL OF EVIDENCE: NA. Laryngoscope, 123:2189-2194, 2013.

Introduction: We describe a novel, clinically applicable conduction study of the laryngeal nerves. Methods: Seventeen normal volunteer subjects were included. Activation of the sensory territory of the superior laryngeal nerve was performed by administration of low level brief electrical stimuli. The laryngeal closure reflex (LCR) evoked by this stimulus was recorded by needle electrodes. Mean minimal latencies were calculated for each response, and proposed values for the upper limit of normal were determined. Results: Uniform, consistent early ipsilateral responses and late bilateral responses, which exhibit greater variation in latency and morphology, were recorded. Significant side-to-side differences in latencies were observed, consistent with the length discrepancy between right and left recurrent laryngeal nerves. Conclusions: This technique yields clear, quantifiable data regarding neurologic integrity of laryngeal function, heretofore unobtainable in the clinical setting. This study may yield clinically relevant information regarding severity and prognosis in patients with laryngeal neuropathic injury. Muscle Nerve 47:432-436, 2013.

OBJECTIVES: We utilized dynamic magnetic resonance imaging to visualize the pharynx and upper esophageal segment in normal, healthy subjects. METHODS: A 3-T scanner with a 4-channel head coil and a dual-channel neck coil was used to obtain high-speed magnetic resonance images of subjects who were swallowing liquids and pudding. Ninety sequential images were acquired with a temporal resolution of 113 ms. Imaging was performed in axial planes at the levels of the oropharynx and the pharyngoesophageal segment. The images were then analyzed for variables related to alterations in the area of the pharynx and pharyngoesophageal segment during swallowing, as well as temporal measures related to these structures. RESULTS: All subjects tolerated the study protocol without complaint. Changes in the area of the pharyngeal wall lumen and temporal measurements were consistent within and between subjects. The inter-rater and intra-rater reliabilities for the measurement tool were excellent. CONCLUSIONS: Dynamic magnetic resonance imaging of the swallow sequence is both feasible and reliable and may eventually complement currently used diagnostic methods, as it adds substantive information.

OBJECTIVES/HYPOTHESIS: Although clinical dogma suggests the value of laryngeal visualization (flexible laryngoscopy and stroboscopy) in dysphonic patients, recently published clinical guidelines suggest that, in many cases, history and/or physical examination are sufficient to guide clinical decision-making regarding the timing of such examinations. We sought to prospectively quantify the diagnostic accuracy of history, laryngoscopy, and stroboscopy using direct laryngoscopy as the gold standard. STUDY DESIGN: Expert survey. METHODS: Six laryngologists were presented with vignettes including history and physical examination (HPE), laryngosocpy, and stroboscopy. Questions regarding diagnosis, the certainty of diagnosis, and subsequent management plans were posed. Operative findings via direct laryngoscopy were employed as a comparator. RESULTS: The diagnostic accuracy of HPE was quite low (5%). The accuracy of diagnosis increased substantially following laryngeal imaging; 68.3% for both flexible laryngoscopy and stroboscopy. Particular diagnoses were more consistently identified; cancer, for example, was much more accurately identified on laryngoscopy (100%) and stroboscopy (100%) rather than HPE alone (33%). Cancer was selected as the diagnosis in 10 of 60 HPEs, though was only correct once and missed in five cases. In contrast, no diagnoses of cancer were missed following laryngoscopic and/or stroboscopic examinations. CONCLUSION: These findings confirm the value of laryngeal visualization (flexible laryngoscopy and stroboscopy) in dysphonic patients, and the lack of accuracy of history and physical examination in determining the diagnosis in patients with hoarseness. Laryngoscope, 2013.

OBJECTIVES/HYPOTHESIS: To characterize fundamental late tissue effects in the human vocal fold following radiation therapy. To develop a murine model of radiation fibrosis in order to ultimately develop both treatment and prevention paradigms. DESIGN: Translational study using archived human and fresh murine irradiated vocal fold tissue. METHODS: 1) Irradiated vocal fold tissue from patients undergoing laryngectomy for loss of function from radiation fibrosis was identified from pathology archives. Histomorphometry, immunohistochemistry, and whole-genome microarray, as well as real-time transcriptional analyses, were performed. 2) Focused radiation to the head and neck was delivered to mice in a survival fashion. One month following radiation, vocal fold tissue was analyzed with histomorphometry, immunohistochemistry, and real-time PCR transcriptional analysis for selected markers of fibrosis. RESULTS: Human irradiated vocal folds demonstrated increased collagen transcription, with increased deposition and disorganization of collagen in both the thyroarytenoid muscle and the superficial lamina propria. Fibronectin were increased in the superficial lamina propria. Laminin decreased in the thyroarytenoid muscle. Whole genome microarray analysis demonstrated increased transcription of markers for fibrosis, oxidative stress, inflammation, glycosaminoglycan production, and apoptosis. Irradiated murine vocal folds demonstrated increases in collagen and fibronectin transcription and deposition in the lamina propria. Transforming growth factor (TGF)-beta increased in the lamina propria. CONCLUSION: Human irradiated vocal folds demonstrate molecular changes leading to fibrosis that underlie loss of vocal fold pliability occurring in patients following laryngeal irradiation. The irradiated murine tissue demonstrates similar findings, and this mouse model may have utility in creating prevention and treatment strategies for vocal fold radiation fibrosis.

OBJECTIVE/HYPOTHESIS: To determine the efficacy of the potassium titanyl phosphate (KTP) laser in lesion reduction, as well as preservation of mucosal wave and glottic closure in a cohort of patients with benign laryngeal pathology across multiple institutions. STUDY DESIGN: Multi-institutional and retrospective. METHODS: One hundred two patients who underwent in-office KTP procedures at multiple academic laryngology practices with at least a single follow-up visit were included. Image analysis was used to quantify vocal fold lesion size before and after treatment. A subset of images was analyzed by expert reviewers to determine the impact of this treatment on glottic closure and mucosal wave. RESULTS: Statistically, when considering all lesions, KTP induced a significant reduction in lesion size. Post hoc analyses revealed some lesion specificity; all lesions decreased in size, with the exception of vocal fold scar. Mucosal wave and glottic closure were improved or unchanged in more than 90% of the patients examined. The inter- and intrarater reliabilities of the lesion quantification method were excellent. CONCLUSIONS: With great care and insight, the KTP laser appears to be a valuable tool for the treatment of various benign laryngeal lesions. Furthermore, KTP laser therapy appears to preserve or improve mucosal wave and glottic closure. The lesion measurement protocol previously described by our group appears to be reliable.