Faculty Bibliography

OBJECTIVES: Based on our laboratory's newly confirmed motor pathway for glottic closure, we measured the glottic closing force (GCF) during isolated stimulation of the external branch of the superior laryngeal nerve (eSLN) in the porcine model. Glottic closure is 1 of the primary mechanisms for prevention of aspiration during deglutition. METHODS: The recurrent laryngeal nerve (RLN) and eSLN were identified bilaterally in 4 porcine necks. Subsequently, GCF was measured with a pressure transducer as the distal ends of individual nerves were stimulated in 4 animals. The RLN mediated GCF was measured first, followed by isolated eSLN mediated GCF, followed by transection of the RLN and repeat measurement of the eSLN GCF. Ultimately, the cricothyroid (CT) muscle attachment was released and the GCF measured. RESULTS: The GCF during isolated eSLN stimulation before and after RLN transection is approximately 89% of the RLN mediated GCF in each animal. The GCF after CT release is approximately 84% of the RLN perceived GCF. Transection of the RLN did not alter the eSLN observed GCF. CONCLUSIONS: The GCF obtained during isolated eSLN stimulation is adequate for delivery of an appropriate laryngeal protective response and may be considered a target motor nerve for augmenting GCF in selected rehab settings.

BACKGROUND: Signal transducer and activator 1 (STAT-1) mutations are rare and have been implicated in combined immunodeficiency, enhanced tumorigenesis, and vascular defects. METHODS: A 60-year-old woman with a novel STAT-1 mutation and resulting immunodeficiency, squamous cell carcinoma, and vascular disease presented with profuse epistaxis secondary to rupture of an aberrant artery that she developed in part because of this mutation. After unsuccessful posterior packing, embolization was initiated but subsequently aborted because of a bovine origin carotid artery and a history of multiple carotid dissections. RESULTS: After repeat posterior packing, hemostasis was achieved. No additional episodes of epistaxis occurred in the subsequent 13 months. CONCLUSION: Vascular anomalies can present challenges in epistaxis management. In patients with conditions known to cause vascular anomalies, it is critical to obtain vascular imaging before intervention.

Objectives Intraoperative vagus nerve monitoring during skull base surgery has been reported with the use of an oral nerve monitoring endotracheal tube. However, the intraoral presence of an endotracheal tube can limit exposure by its location in the operative field during transfacial approaches and by limiting superior mobilization of the mandible during transcervical approaches. We describe a transnasal vagus nerve monitoring technique. Design and Participants Ten patients underwent open skull base surgery. Surgical approaches included transcervical (five), transfacial/maxillary swing (three), and double mandibular osteotomy (two). The vagus nerve was identified, stimulated, and monitored in all cases. Main Outcome Measures Intraoperative nerve stimulation, pre- and postoperative vagus nerve function through the use of flexible laryngoscopy in conjunction with assessment of subjective symptoms of hoarseness, voice change, and swallowing difficulty. Results Three patients had extensive involvement of the nerve by tumor with complete postoperative nerve deficit, one patient had a transient deficit following dissection of tumor off of nerve with resolution, and the remaining patients had nerve preservation. One patient experienced minor epistaxis during monitor tube placement that was managed conservatively. Conclusions Transnasal vagal nerve monitoring is a simple method that allows for intraoperative monitoring during nerve preservation surgery without limiting surgical exposure.

OBJECTIVES/HYPOTHESIS: Cross-innervation patterns to the thyroarytenoid (TA) muscle have long been sought after. We have identified in the porcine model, cross-innervation by way of the external branch of the superior laryngeal nerve (eSLN). STUDY DESIGN: Experimental study. METHODS: TA contraction was electromyographically recorded when electrically stimulating the eSLN in six porcine necks. The recurrent laryngeal nerve (RLN) was subsequently transected. The insertion of the cricothyroid (CT) muscle on the cricoid was then subsequently removed as well. RESULTS: Stimulation of the eSLN rendered a response from the TA muscle in 6/6 subject necks, with a mean latency of 2.76 msec. TA muscle contraction by way of eSLN stimulation persisted after the RLN was transected and after CT insertion release. CONCLUSIONS: The TA muscle is directly cross-innervated by a branch of the eSLN in the porcine model. This finding may have implications regarding possible future laryngeal pacing strategies and could be a target nerve for rehabilitation.

IMPORTANCE: There continues to be a paucity of data regarding the pharyngeal plexus (PP) and its interconnectivity with the laryngeal nerves and function. OBJECTIVE: To identify the specific neural pathways involved in the glottic closure reflex (GCR)-like pathway of the PP and other pathways to the thyroarytenoid (TA) muscle in the porcine model. DESIGN, SETTING, AND ANIMAL SUBJECTS: Animal experimental study from September 2013 to June 2014 conducted in a tertiary academic medical center on male Yorkshire pigs. INTERVENTIONS: Contraction of the TA was detected with electromyography (EMG) during electrical stimulation of the PP in 7 porcine necks. Subsequently, the external branch of the superior laryngeal nerve (eSLN), communicating nerve of Galen (NG), and the recurrent laryngeal nerve (RLN) were sequentially transected to help elucidate the path of neural conduction. MAIN OUTCOMES AND MEASURES: Confirmation of TA muscle contraction by EMG. RESULTS: Stimulation of the PP evoked a response from the TA muscle in 6 of 7 subject animals. In 3 of 7 subjects, a long latency response (mean, 14.62 milliseconds) was identified, which was eliminated only after transection of the RLN. In 3 of 7 subjects, a short latency response (mean 3.05 milliseconds) was identified, which disappeared in 1 subject each by eSLN, RLN, and NG transection. CONCLUSIONS AND RELEVANCE: We identified the specific neural pathway involved in the PP's GCR-like pathway. We also noted a variable direct pattern of innervation to the TA.

Quantitative levels of harmful oral microbes present following complex surgical excisions of head and neck cancer are important since wounds are often contaminated through direct connection to the oral cavity and its flora. This possibility is especially important in irradiated patients who have decreased protective salivary function. In addition, high oral microbial levels increase and intensify oral mucositis leading to significant morbidity in patients treated with radiation therapy. One previously untested surgical teaching to decrease the bacterial inoculum present in the oral cavity is to counsel patients against consuming otherwise nutritious dairy products, as they are thought to coat the oral cavity with rate-limiting nutrients vital for bacterial growth. This risk may extend to individuals with chronic laryngeal penetration or aspiration, since salivary bacterial load might represent a lethal threat in the presence of marginal pulmonary reserve. A crossover study using six healthy adult volunteers and six patients who had previously undergone radiation therapy to an oropharyngeal primary site was performed. Saliva samples were quantitatively cultured in both groups with and without the consumption of dairy products at 1-h and 5-h intervals. Analysis of quantitative cultures demonstrated that the consumption of dairy products had no influence on bacterial levels present in previously radiated subjects and nonirradiated controls. Additionally, the consumption of dairy did not affect the composition of microbes present. Due to the lack of changes in both quantity and composition of oral bacteria seen in this study, patients would not benefit from the avoidance of dairy products.

OBJECTIVES/HYPOTHESIS: The aim of this study was to elucidate whether the pharyngeal plexus (PP) contributes to vocal cord adduction in the porcine model. STUDY DESIGN: Experimental study. METHODS: Thyroarytenoid (TA) muscle contraction was recorded electromyographically with electrical stimulation of the internal branch of the superior laryngeal nerve (iSLN) and PP in seven pigs. RESULTS: Glottic closure reflex (GCR) was detected with stimulation of the iSLN in all subjects. Electrical stimulation of the PP elicited a response from the TA in six of the seven pigs. In one subject, TA electromyography (EMG) mean latency was noted to be 18.8 msec, approximating that of GCR elicited by iSLN stimulation. Antidromic nerve pulses generated the responses from the TA with a medium latency (mean, 6.32 msec) in three of the seven pigs. TA EMG with a short latency (mean, 1.8 msec) was identified in two of the seven pigs. CONCLUSIONS: Electrical stimulation of both central and distal ends of the PP elicited vocal cord adduction. These results support the promise of future rehabilitative uses of the PP to treat dysfunctions of the iSLN or as a means of addressing many age-related or metabolic causes of protective laryngeal paresis. LEVEL OF EVIDENCE: NA.

OBJECTIVES/HYPOTHESIS: The purpose of this study was to investigate the prevalence of vocal pathology among first-year acting students. STUDY DESIGN: A retrospective review of 30 first-year graduate-level drama students between 2009 and 2011 was performed. METHODS: Stroboscopy, Voice Handicap Index-10 questionnaires, and acoustic measures were analyzed. RESULTS: The prevalence of incomplete glottal closure, laryngeal hyperfunction, and decreased mucosal wave was 62%, 59%, and 55%, respectively. Laryngoscopic findings consistent with laryngopharyngeal reflux (LPR) were demonstrated in 48% of subjects. Subgroup analysis of laryngeal hyperfunctioning (HF) and nonhyperfunctioning drama students revealed an increased prevalence of all videostroboscopic abnormalities in the HF group. The increased prevalence of LPR stigmata in HF actors reached statistical significance (P = 0.04). CONCLUSIONS: The vocal demands of actors are unique, requiring the effective use of volume, pitch control, and endurance. This is the first study that systematically analyzes the prevalence of vocal pathology in actors. This study will continue throughout their education, anticipating that our feedback along with their vocal training will improve outcomes.

BACKGROUND: Microtia reconstruction remains one of the most challenging procedures encountered by the reconstructive surgeon. A national report on the current management of microtia has never been presented before. The purpose of this project was to survey members of the American Society of Plastic Surgeons (ASPS) to identify their preferences and practices and report their opinions regarding issues related to microtia reconstruction. METHODS: An anonymous web-based survey consisting of 19 questions was distributed to the members of the ASPS. Questions focused on the management of microtia. The study design was descriptive, using categorical data analysis. RESULTS: Thirty-eight percent of all respondents perform microtia reconstruction; 91 % learned the autogenous cartilage-based reconstruction technique, while only 16 % were exposed to alloplastic reconstruction. Seventy percent of all respondents learned autogenous cartilage-based ear reconstruction exclusively. Fifty percent of respondents who perform microtia reconstruction reported a steep learning curve. In the pediatric patient population, 49 % of microtia surgeons prefer performing the surgery when the patient is between 7 and 10 years of age, while 40 % of microtia surgeons prefer the patient to be 4-6 years of age. Fifty-nine percent of all respondents believe that in 15 years tissue engineering will represent the gold standard of microtia reconstruction. CONCLUSION: Staged microtia repair using autogenous cartilage remains the heavily favored method of microtia reconstruction among plastic surgeons. Moreover, there is a deficiency in training the newer surgical techniques, such as alloplastic and osseointegrated options. This study also highlights the continuing need to elucidate the optimal timing for microtia repair in the pediatric patient to mitigate the potential psychosocial morbidity well described in the literature. LEVEL OF EVIDENCE V: This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .