Faculty Bibliography

OBJECTIVES:The current study aimed to identify and map the available evidence surrounding cochlear implantation (CI) in older adults. Five outcomes were evaluated: speech perception scores, perioperative complications, neurocognitive outcomes, quality of life outcomes and vestibular dysfunction and fall rates after surgery. METHODS:A scoping review was performed in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analysis extension for Scoping Reviews and included patients over the age of 60. RESULTS:Ninety-seven studies met inclusion criteria, encompassing 7,182 patients. Mean (SD) speech perception scores in quiet and in noise pre-and postoperatively were 7.9% (6.7) and 52.8% (14.3) and 8.0% (68.1) and 68.1% (15.9) respectively. Postoperative cardiac arrhythmias, urinary retention, and delirium occurred slightly more frequently in older adults. In terms of cognition, most studies noted stability or improvement one year after implantation. A majority of studies indicated better quality of life post-CI. Rates of fall after surgery were rarely reported, and there was a general paucity of data surrounding vestibular function changes after CI. DISCUSSION:This scoping review identifies many positive outcomes linked to CI in older adults. No findings suggest a single patient characteristic that would warrant refusal to consider evaluation for cochlear implantation.

BACKGROUND:The recent trends in education and geographic distribution of the head and neck surgery workforce have not been studied extensively. METHODS:We reviewed publicly available sources to locate all fellowship-trained head and neck surgeons and recent graduates. The number of surgeons in each state was compared against head and neck cancer incidence data from the Centers for Disease Control. RESULTS:The number of graduates increased annually by 1 per 100 000 000 people from 2011-2020. The average number of fellowship-trained surgeons per state was 10 (SD: 12). The average number of new head and neck cancer cases per surgeon was 247 (SD: 135). Ten states (20%) had cases >1 SD above the national average/surgeon, while 3 (6%) had cases >1 SD below the national average. CONCLUSION/CONCLUSIONS:Head and neck surgeons are located in most states, but not uniformly. Most states have approximately average density of surgeons; however, several states are outliers.

BACKGROUND:Few studies have investigated the needs of head and neck surgery trainees and areas for improvement of fellowship programs. METHODS:We conducted a qualitative study by interviewing a nationally representative sample of program directors and national leaders in head and neck surgery. We asked about the current state and strengths of training; and areas for further improvement. All interviews were independently coded and analyzed by two reviewers. RESULTS:All experts (100%) believed that the current training provides a strong foundation and furthermore, a standardized curriculum is beneficial. Multidisciplinary training (80%), participation in tumor boards (75%), and a syllabus (60%) were the most frequently mentioned components. Most believed that a formal certification process would be beneficial (73%), though there was no consensus on the format. CONCLUSION/CONCLUSIONS:Experts in head and neck surgery are generally in favor of a standardized curriculum. Further discussions of a formal certification process might be warranted.

Macrophage phenotypes are simplistically classified as pro-inflammatory (M1) or anti-inflammatory/pro-fibrotic (M2). Phenotypically different macrophages are putatively involved in vocal fold (VF) fibrosis. The current study investigated interactions between macrophages and VF fibroblasts. THP-1 monocyte-derived macrophages were treated with interferon-gamma (IFN-γ), lipopolysaccharide (LPS)/IFN-γ, interleukin-10 (IL10), transforming growth factor-β1 (TGF-β), or interleukin-4 (IL4) for 24 h (M(IFN), M(IFN/LPS), M(IL10), M(TGF), and M(IL4), respectively; M(-) denotes untreated macrophages). Differentially activated macrophages and human VF fibroblasts were co-cultured ± direct contact. Expression of CXCL10, CCN2, ACTA2, FN1, TGM2, and LOX was quantified by real-time polymerase chain reaction. Type I collagen and smooth muscle actin (SMA) were observed by immunofluorescence. CXCL10 and PTGS2 were upregulated in fibroblasts indirectly co-cultured with M(IFN) and M(IFN/LPS). M(TGF) stimulated CCN2, ACTA2, and FN1 in fibroblasts. Enzymes involved in extracellular matrix crosslinking (TGM2, LOX) were increased in monocultured M(IL4) compared to M(-). Direct co-culture with all macrophages increased type I collagen and SMA in fibroblasts. Macrophage phenotypic shift was consistent with stimulation and had downstream differential effects on VF fibroblasts. Direct contact with macrophages, regardless of phenotype, stimulated a pro-fibrotic response in VF fibroblasts. Collectively, these data suggest meaningful interactions between macrophages and fibroblasts mediate fibrosis.

BACKGROUND:The current study aims to characterize the natural history of sporadic vestibular schwannoma volumetric tumor growth, including long-term growth patterns following initial detection of growth. METHODS:Volumetric tumor measurements from 3,505 serial MRI studies were analyzed from unselected consecutive patients undergoing wait-and-scan management at three tertiary referral centers between 1998 and 2018. Volumetric tumor growth was defined as a change in volume ≥20%. RESULTS:Among 952 patients undergoing observation, 622 experienced tumor growth with initial growth-free survival rates (95% CI) at 1, 3, and 5 years following diagnosis of 66% (63-69), 30% (27-34), and 20% (17-24). Among 405 patients who continued to be observed despite demonstrating initial growth, 210 experienced subsequent tumor growth with subsequent growth-free survival rates at 1, 3, and 5 years following initial growth of 77% (72-81), 37% (31-43), and 24% (18-31). Larger tumor volume at initial growth (HR 1.13, p=0.02) and increasing tumor growth rate (HR 1.31; p<0.001) were significantly associated with an increased likelihood of subsequent growth, whereas a longer duration of time between diagnosis and detection of initial growth was protective (HR 0.69; p<0.001). CONCLUSIONS:While most vestibular schwannomas exhibit an overall propensity for volumetric growth following diagnosis, prior tumor growth does not perfectly predict future growth. Tumors can subsequently grow faster, slower, or demonstrate quiescence and stability. Larger tumor size and increasing tumor growth rate portend a higher likelihood of continued growth. These findings can inform timing of intervention: whether upfront at initial diagnosis, after detection of initial growth, or only after continued growth is observed.

The aim of this multicenter retrospective study is to characterize the histopathologic features of initial/early biopsies of proliferative leukoplakia (PL; also known as proliferative verrucous leukoplakia), and to analyze the correlation between histopathologic features and malignant transformation (MT). Patients with a clinical diagnosis of PL who have at least one biopsy and one follow-up visit were included in this study. Initial/early biopsy specimens were reviewed. The biopsies were evaluated for the presence of squamous cell carcinoma (SCCa), oral epithelial dysplasia (OED), and atypical verrucous hyperplasia (AVH). Cases that lacked unequivocal features of dysplasia were termed "hyperkeratosis/parakeratosis not reactive (HkNR)". Pearson chi-square test and Wilcoxon test were used for statistical analysis. There were 86 early/initial biopsies from 59 patients; 74.6% were females. Most of the cases had a smooth/homogenous (34.8%) or fissured appearance (32.6%), and only 13.0% had a verrucous appearance. The most common biopsy site was the gingiva/alveolar mucosa (40.8%) and buccal mucosa (25.0%). The most common histologic diagnosis was OED (53.5%) followed by HkNR (31.4%). Of note, two-thirds of HkNR cases showed only hyperkeratosis and epithelial atrophy. A lymphocytic band was seen in 34.8% of OED cases and 29.6% of HkNR cases, mostly associated with epithelial atrophy. Twenty-eight patients (47.5%) developed carcinoma and 28.9% of early/initial biopsy sites underwent MT. The mortality rate was 11.9%. Our findings show that one-third of cases of PL do not show OED with most exhibiting hyperkeratosis and epithelial atrophy, but MT nevertheless occurred at such sites in 3.7% of cases.

OBJECTIVES/HYPOTHESIS/OBJECTIVE:Fibula flaps are routinely used for osseous reconstruction of head and neck defects. However, single-barrel fibula flaps may result in a height discrepancy between native mandible and grafted bone, limiting outcomes from both an aesthetic and dental standpoint. The double-barrel fibula flap aims to resolve this. We present our institution's outcomes comparing both flap designs. STUDY DESIGN/METHODS:Retrospective cohort study. METHODS:We conducted a retrospective review of all patients undergoing free fibula flap mandibular reconstruction at our institution between October 2008 and October 2020. Patients were grouped based on whether they underwent single-barrel or double-barrel reconstruction. Postoperative outcomes data were collected and compared between groups. Differences in categorical and continuous variables were assessed using a Chi-square test or Student's t-test, respectively. RESULTS:Out of 168 patients, 126 underwent single-barrel and 42 underwent double-barrel reconstruction. There was no significant difference in postoperative morbidity between approaches, including total complications (P = .37), flap-related complications (P = .62), takeback to the operating room (P = .75), flap salvage (P = .66), flap failure (P = .45), and mortality (P = .19). In addition, there was no significant difference in operative time (P = .86) or duration of hospital stay (P = .17). After adjusting for confounders, primary dental implantation was significantly higher in the double-barrel group (odds ratio, 3.02; 95% confidence interval, 1.2-7.6; P = .019). CONCLUSION/CONCLUSIONS:Double-barrel fibula flap mandibular reconstruction can be performed safely without increased postoperative morbidity or duration of hospital stay relative to single-barrel reconstruction. Moreover, the double-barrel approach is associated with higher odds of primary dental implantation and may warrant further consideration as part of an expanded toolkit for achieving early dental rehabilitation. LEVEL OF EVIDENCE/METHODS:III Laryngoscope, 2021.

Vocalizations are often elaborate, rhythmically structured behaviors. Vocal motor patterns require close coordination of neural circuits governing the muscles of the larynx, jaw, and respiratory system. In the elaborate vocalization of Alston's singing mouse (Scotinomys teguina) each note of its rapid, frequency-modulated trill is accompanied by equally rapid modulation of breath and gape. To elucidate the neural circuitry underlying this behavior, we introduced the polysynaptic retrograde neuronal tracer pseudorabies virus (PRV) into the cricothyroid and digastricus muscles, which control frequency modulation and jaw opening, respectively. Each virus singly labels ipsilateral motoneurons (nucleus ambiguus for cricothyroid, and motor trigeminal nucleus for digastricus). We find that the two isogenic viruses heavily and bilaterally colabel neurons in the gigantocellular reticular formation, a putative central pattern generator. The viruses also show strong colabeling in compartments of the midbrain including the ventrolateral periaqueductal gray and the parabrachial nucleus, two structures strongly implicated in vocalizations. In the forebrain, regions important to social cognition and energy balance both exhibit extensive colabeling. This includes the paraventricular and arcuate nuclei of the hypothalamus, the lateral hypothalamus, preoptic area, extended amygdala, central amygdala, and the bed nucleus of the stria terminalis. Finally, we find doubly labeled neurons in M1 motor cortex previously described as laryngeal, as well as in the prelimbic cortex, which indicate these cortical regions play a role in vocal production. The progress of both viruses is broadly consistent with vertebrate-general patterns of vocal circuitry, as well as with circuit models derived from primate literature.

OBJECTIVES/HYPOTHESIS/OBJECTIVE:The aim of this study was to obtain a reliable estimate of single-sided deafness (SSD) prevalence in the adult U.S. POPULATION/METHODS/: METHODS:A cross-sectional national epidemiologic study was performed. Participants were included from the National Health and Nutrition Examination Survey (NHANES). Each cohort includes a nationally representative sample of approximately 5,000 noninstitutionalized civilians. Subjects 20 years old and over with audiometric testing were included. SSD was defined as normal hearing (pure-tone average [PTA] of ≤25 dB) in one ear and severe or worse hearing (PTA > 70 dB) in the other, using both three- and four-frequency PTA definition. Prevalence was measured as a raw number (n) and percentage (%) of the sample. Weighted estimates of prevalence were calculated based on the 2019 U.S. population census. RESULTS:An estimated 345,064 Americans (estimated prevalence of 0.14%, 95% confidence interval = 0.08-0.24) had SSD. SSD was more prevalent in individuals 60 to 79 years of age (estimated 155,917 U.S. adults, prevalence of 0.25%). A higher prevalence of SSD was noted among women compared to men (215,430 U.S. adult women, prevalence of 0.17% vs. 131,726 U.S. adult men, prevalence of 0.11%). Using a three-frequency PTA definition resulted in an estimated prevalence of 0.11%. Finally, 27% of adults with SSD reported having "good" or "excellent" hearing despite their hearing loss. CONCLUSIONS:The prevalence of SSD in the United States is estimated at 0.11%-0.14% (271,122 to 345,064 adults), depending on PTA definition used. These individuals could potentially benefit from auditory rehabilitation, including cochlear implantation. LEVEL OF EVIDENCE/METHODS:2 Laryngoscope, 2021.