Surgical management of vocal cord nodules in children: Trends and outcomes.

OBJECTIVES: Vocal cord nodules (VCNs) are the most common cause of dysphonia in school-aged children, with potential negative impacts on quality of life including diminished self-esteem and academic performance. The standard of care for VCNs is conservative management which ranges from voice hygiene to speech therapy with a focus on voice otherwise known as voice therapy, with surgical excision reserved for refractory cases. Thus, few studies have analyzed outcomes of surgical management of VCNs. The purpose of this study is to assess the prevalence and efficacy of surgical excision of VCNs when compared to speech therapy. METHODS: Children with VCNs seen at a single tertiary care institution between 2015 and 2020 were identified by ICD-9 code 478.5 and ICD-10 code J38.2. Demographics, objective voice assessment, intervention, and follow-up assessment data were reviewed. Frequencies, medians, and interquartile ranges were calculated. Time to resolution and improvement were assessed by Cox proportional hazards model. Univariate logistic regression was performed. A P value of <0.05 was considered statistically significant. RESULTS: Three hundred sixty-eight patients diagnosed with VCNs were identified. 169 patients received intervention for VCNs, with 159 (43.2 %) receiving speech therapy alone and 5 (1.4 %) receiving surgery alone. On bivariate analysis, there was no significant difference in demographic features between treatment groups, however speech therapy patients did have a longer follow-up time. 154 patients underwent objective voice assessment at the time of VCN diagnosis. Among these patients, 95 (61.7 %) received speech therapy and 59 (40.3 %) received no intervention. Speech therapy patients had significantly higher pVHI scores, however there was no significant difference in CAPE-V Overall Severity scores or computerized voice assessment analysis. On Cox proportional hazards analysis, surgical intervention was associated with faster resolution and faster improvement of dysphonic symptoms. On binary logistic regression, surgery was associated with a significantly greater proportion of patients reporting resolution of dysphonic symptoms, however there was no significant difference in proportion of patients reporting improvement of dysphonia. CONCLUSION: For most patients with VCNs, conservative measures such as voice hygiene and speech therapy remain first line, however certain patients may benefit from the rapid improvement and resolution of symptoms that surgical intervention may provide.

Long-Term Chondrocyte Retention in Partially Decellularized Tracheal Grafts.

OBJECTIVE: Decellularized tracheal grafts possess the biological cues necessary for tissue regeneration. However, conventional decellularization approaches to target the removal of all cell populations including chondrocytes lead to a loss of mechanical support. We have created a partially decellularized tracheal graft (PDTG) that preserves donor chondrocytes and the mechanical properties of the trachea. In this study, we measured PDTG chondrocyte retention with a murine microsurgical model. STUDY DESIGN: Murine in vivo time-point study. SETTING: Research Institute affiliated with Tertiary Pediatric Hospital. METHODS: PDTG was created using a sodium dodecyl sulfate protocol. Partially decellularized and syngeneic grafts were orthotopically implanted into female C57BL/6J mice. Grafts were recovered at 1, 3, and 6 months postimplant. Pre- and postimplant grafts were processed and analyzed via quantitative immunofluorescence. Chondrocytes (SOX9+, DAPI+) present in the host and graft cartilage was evaluated using ImageJ. RESULTS: Partial decellularization resulted in the maintenance of gross tracheal architecture with the removal of epithelial and submucosal structures on histology. All grafts demonstrated SOX9+ chondrocytes throughout the study time points. Chondrocytes in PDTG were lower at 6 months compared to preimplant and syngeneic controls. CONCLUSION: PDTG retained donor graft chondrocytes at all time points. However, PDTG exhibits a reduction in chondrocytes at 6 months. The impact of these histologic changes on cartilage extracellular matrix regeneration and repair remains unclear.

The pediatric indications for tonsillectomy and adenotonsillectomy: Race/ethnicity, age, and gender.

Objective: To evaluate how pediatric indications for tonsillectomy or adenotonsillectomy relate to gender, race/ethnicity, and age. Methods: Included consecutive pediatric patients who underwent tonsillectomy or adenotonsillectomy from a single tertiary academic institution between 2012 and 2019. Logistic regression analysis was used to measure association between the indication for tonsillectomy and the demographic variables gender, race/ethnicity, and age. Results: Of the 1106 children included in this study, 53% were male and 47% were female. Half of the children were White, 40% were African American, 6% were Hispanic and 4% were other. The most common indication for surgery was upper airway obstruction alone (66%), followed by obstruction and infection (22%), and recurrent infections (12%). We found that male gender (OR 1.59, 95% CI 1.24-2.04), African American race (OR 2.76, 95% CI 2.08-3.65), and younger age were associated with greater odds of presenting with upper airway obstruction as the indication for tonsillectomy. Conversely, male gender (OR 0.63, 95% CI 0.44-0.92), African American race (OR 0.4, 95% CI 0.26-0.61), and younger age were associated with lower odds of presenting with recurrent infection as the indication for tonsillectomy. Conclusions: Male gender, African American race, and young age are risk factors for tonsillar surgery due to airway obstruction. Female gender, White race, and older age are risk factors for tonsillar surgery due to recurrent throat infections. Level of Evidence: 3.

Optimization of Chondrocyte Viability in Partially Decellularized Tracheal Grafts.

OBJECTIVE: Advancements in tissue-engineered tracheal replacement (TETR) show promise for the use of partially decellularized tracheal grafts (PDTG) to address critical gaps in airway management and reconstruction. In this study, aiming to leverage the immunoprivileged nature of cartilage to preserve tracheal biomechanics, we optimize PDTG for retention of native chondrocytes. STUDY DESIGN: Comparison in vivo murine study. SETTING: Research Institute affiliated with Tertiary Pediatric Hospital. METHODS: PDTG were created per a shortened decellularization protocol using sodium dodecyl sulfate, then biobanked via cryopreservation technique. Decellularization efficiency was characterized by DNA assay and histology. Viability and apoptosis of chondrocytes in preimplanted PDTG and biobanked native trachea (control) was assessed with live/dead and apoptosis assays. PDTG (N = 5) and native trachea (N = 6) were orthotopically implanted in syngeneic recipients for 1-month. At the endpoint, microcomputed tomography (micro-CT) was employed to interrogate graft patency and radiodensity in vivo. Vascularization and epithelialization were qualitatively analyzed using histology images following explant. RESULTS: PDTG exhibited complete decellularization of all extra-cartilaginous cells and reduced DNA content compared to control. Chondrocyte viability and nonapoptotic cell populations were improved utilizing biobanking and shorter decellularization time. All grafts remained patent. Evaluation of graft radiodensity at 1 month revealed elevation of Hounsfield units in both PDTG and native compared to host, with PDTG showing higher radiodensity than native. PDTG supported complete epithelialization and functional reendothelialization 1-month postimplantation. CONCLUSION: Optimizing PDTG chondrocyte viability is a key component to successful tracheal replacement. Ongoing research seeks to evaluate the acute and chronic immunogenicity of PDTG.

Outcomes After Transcutaneous Bone-Conduction Implantation in Adults and Children.

OBJECTIVE: To evaluate clinical and audiometric outcomes of adult and pediatric patients implanted with a semi-implantable transcutaneous active bone-conduction implant. STUDY DESIGN: Retrospective chart review. SETTING: Two tertiary referral centers. PATIENTS: Subjects implanted with the semi-implantable transcutaneous active bone-conduction implant called BoneBridge. INTERVENTION: Implantation of the BoneBridge and audiometric evaluations. MAIN OUTCOME MEASURES: Audiometric, clinical, and surgical outcomes as well as complications. RESULTS: Forty-two adults and 20 children were implanted for conductive or mixed hearing loss as well as single-sided deafness. Implantation significantly improved mean air-conduction pure-tone average from 72.8 ± 22.3 to 35 ± 9 dB in adults and from 65.7 ± 24.3 to 19.6 ± 8.2 dB in children (both p < 0.001). Word recognition score improved from 63.7 ± 38.8% to 85.6 ± 10.6% in adults and 57.8 ± 38% to 89.3 ± 10.1% in children (both p < 0.05). The rate of revision surgery was 11.3%, with four patients (6.5%) undergoing removal for device-related complications, two (3.2%) for complications associated with implantation, and one (1.6%) for device failure secondary to external trauma. CONCLUSIONS: In a large retrospective series consisting of both pediatric and adult patients, implantation with a transcutaneous active bone-conduction implant was found to be a reliable aural rehabilitation option for a variety of hearing loss etiologies.

Successful Early Neovascularization in Composite Tracheal Grafts.

OBJECTIVE: Long-segment tracheal defects require tissue replacement for successful reconstruction. Rapid revascularization is imperative to maintain graft function. We previously showed that partially decellularized tracheal grafts (PDTG) and composite tracheal grafts (CTG; PDTG supported by a 3-dimensionally printed external splint) regenerate respiratory epithelium and may support the regeneration of endothelial cells (CD31+). However, the capability of graft endothelial cells to organize or contribute to tracheal revascularization remains unclear. In this study, we quantified endothelial cells (CD31+) and neovessel formation in PDTG and CTG. We hypothesize that PDTG and CTG support tracheal neovascularization to a similar extent as surgical (syngeneic tracheal graft [STG]) and native trachea (NT) controls. STUDY DESIGN: The animal study, a randomized control trial. SETTING: Center for Regenerative Medicine, Nationwide Children's Hospital. METHODS: PDTG was created via an established decellularization protocol. Segmental tracheal reconstruction was performed with STG, PDTG, or CTG using a mouse microsurgical model. NT was used as a nonsurgical control. At 1 month, mice were euthanized, grafts harvested, sectioned, and stained with CD31 and hematoxylin and eosin. Neovessel formation was quantified by the number of formed blood vessels in the lamina propria and vessel size (vessel/graft area, mm2 ). RESULTS: Decellularization eliminated all endothelial cells and there were no perfused vessels at implantation. At 1 month, PDTG and CTG supported neovessel formation with tubular vessels lined with endothelial cells. There was no difference in the number or size of vessels compared to controls. CONCLUSION: PDTG and CTG support tracheal endothelial cell regeneration and neovessel formation. Future directions to assess the function, kinetics, and distribution of graft neovessels are needed.

A Multimodal Approach to Quantify Chondrocyte Viability for Airway Tissue Engineering.

OBJECTIVES/HYPOTHESIS: Partially decellularized tracheal scaffolds have emerged as a potential solution for long-segment tracheal defects. These grafts have exhibited regenerative capacity and the preservation of native mechanical properties resulting from the elimination of all highly immunogenic cell types while sparing weakly immunogenic cartilage. With partial decellularization, new considerations must be made about the viability of preserved chondrocytes. In this study, we propose a multimodal approach for quantifying chondrocyte viability for airway tissue engineering. METHODS: Tracheal segments (5 mm) were harvested from C57BL/6 mice, and immediately stored in phosphate-buffered saline at -20°C (PBS-20) or biobanked via cryopreservation. Stored and control (fresh) tracheal grafts were implanted as syngeneic tracheal grafts (STG) for 3 months. STG was scanned with micro-computed tomography (µCT) in vivo. STG subjected to different conditions (fresh, PBS-20, or biobanked) were characterized with live/dead assay, terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL), and von Kossa staining. RESULTS: Live/dead assay detected higher chondrocyte viability in biobanked conditions compared to PBS-20. TUNEL staining indicated that storage conditions did not alter the proportion of apoptotic cells. Biobanking exhibited a lower calcification area than PBS-20 in 3-month post-implanted grafts. Higher radiographic density (Hounsfield units) measured by µCT correlated with more calcification within the tracheal cartilage. CONCLUSIONS: We propose a strategy to assess chondrocyte viability that integrates with vivo imaging and histologic techniques, leveraging their respective strengths and weaknesses. These techniques will support the rational design of partially decellularized tracheal scaffolds. LEVEL OF EVIDENCE: N/A Laryngoscope, 133:512-520, 2023.

Biobanked tracheal basal cells retain the capacity to differentiate.

Objective: While airway epithelial biorepositories have established roles in the study of bronchial progenitor stem (basal) cells, the utility of a bank of tracheal basal cells from pediatric patients, who have or are suspected of having an airway disease, has not been established. In vitro study of these cells can enhance options for tracheal restoration, graft design, and disease modeling. Development of a functional epithelium in these settings is a key measure. The aim of this study was the creation a tracheal basal cell biorepository and assessment of recovered cells. Methods: Pediatric patients undergoing bronchoscopy were identified and endotracheal brush (N = 29) biopsies were collected. Cells were cultured using the modified conditional reprogramming culture (mCRC) method. Samples producing colonies by day 14 were passaged and cryopreserved. To explore differentiation potential, cells were thawed and differentiated using the air-liquid interface (ALI) method. Results: No adverse events were associated with biopsy collection. Of 29 brush biopsies, 16 (55%) were successfully cultured to passage 1/cryopreserved. Samples with higher initial cell yields were more likely to achieve this benchmark. Ten unique donors were then thawed for analysis of differentiation. The average age was 2.2 ± 2.2 years with five donors (50%) having laryngotracheal pathology. Nine donors (90%) demonstrated differentiation capacity at 21 days of culture, as indicated by detection of ciliated cells (ACT+) and mucous cells (MUC5B+). Conclusion: Pediatric tracheal basal cells can be successfully collected and cryopreserved. Recovered cells retain the ability to differentiate into epithelial cell types in vitro. Level of Evidence: Level 3.

Role of Collagen in Airway Mechanics.

Collagen is the most abundant airway extracellular matrix component and is the primary determinant of mechanical airway properties. Abnormal airway collagen deposition is associated with the pathogenesis and progression of airway disease. Thus, understanding how collagen affects healthy airway tissue mechanics is essential. The impact of abnormal collagen deposition and tissue stiffness has been an area of interest in pulmonary diseases such as cystic fibrosis, asthma, and chronic obstructive pulmonary disease. In this review, we discuss (1) the role of collagen in airway mechanics, (2) macro- and micro-scale approaches to quantify airway mechanics, and (3) pathologic changes associated with collagen deposition in airway diseases. These studies provide important insights into the role of collagen in airway mechanics. We summarize their achievements and seek to provide biomechanical clues for targeted therapies and regenerative medicine to treat airway pathology and address airway defects.

Segmentation of Temporal Bone Anatomy for Patient-Specific Virtual Reality Simulation.

OBJECTIVES: Virtual reality (VR) simulation for patient-specific pre-surgical planning and rehearsal requires accurate segmentation of key surgical landmark structures such as the facial nerve, ossicles, and cochlea. The aim of this study was to explore different approaches to segmentation of temporal bone surgical anatomy for patient-specific VR simulation. METHODS: De-identified, clinical computed tomography imaging of 9 pediatric patients aged 3 months to 12 years were obtained retrospectively. The patients represented normal anatomy and key structures were manually segmented using open source software. The OTOPLAN (CAScination AG, Bern, Switzerland) otological planning software was used for guided segmentation. An atlas-based algorithm was used for computerized, automated segmentation. Experience with the different approaches as well as time and resulting models were compared. RESULTS: Manual segmentation was time consuming but also the most flexible. The OTOPLAN software is not designed specifically for our purpose and therefore the number of structures that can be segmented is limited, there was some user-to-user variation as well as volume differences compared with manual segmentation. The atlas-based automated segmentation potentially allows a full range of structures to be segmented and produces segmentations comparable to those of manual segmentation with a processing time that is acceptable because of the minimal user interaction. CONCLUSION: Segmentation is fundamental for patient-specific VR simulation for pre-surgical planning and rehearsal in temporal bone surgery. The automated segmentation algorithm currently offers the most flexible and feasible approach and should be implemented. Further research is needed in relation to cases of abnormal anatomy. LEVEL OF EVIDENCE: 4.

Regeneration of partially decellularized tracheal scaffolds in a mouse model of orthotopic tracheal replacement.

Decellularized tracheal scaffolds offer a potential solution for the repair of long-segment tracheal defects. However, complete decellularization of trachea is complicated by tracheal collapse. We created a partially decellularized tracheal scaffold (DTS) and characterized regeneration in a mouse model of tracheal transplantation. All cell populations except chondrocytes were eliminated from DTS. DTS maintained graft integrity as well as its predominant extracellular matrix (ECM) proteins. We then assessed the performance of DTS in vivo. Grafts formed a functional epithelium by study endpoint (28 days). While initial chondrocyte viability was low, this was found to improve in vivo. We then used atomic force microscopy to quantify micromechanical properties of DTS, demonstrating that orthotopic implantation and graft regeneration lead to the restoration of native tracheal rigidity. We conclude that DTS preserves the cartilage ECM, supports neo-epithelialization, endothelialization and chondrocyte viability, and can serve as a potential solution for long-segment tracheal defects.

Otolaryngology in the Time of Corona: Assessing Operative Impact and Risk During the COVID-19 Crisis.

OBJECTIVE: Limited research exists on the coronavirus disease 2019 (COVID-19) pandemic pertaining to otolaryngology-head and neck surgery (OHNS). The present study seeks to understand the response of OHNS workflows in the context of policy changes and to contribute to developing preparatory guidelines for perioperative management in OHNS. STUDY DESIGN: Retrospective cohort study. SETTING: Pediatric and general adult academic medical centers and a Comprehensive Cancer Center (CCC). SUBJECTS AND METHODS: OHNS cases from March 18 to April 8, 2020-the 3 weeks immediately following the Ohio state-mandated suspension of all elective surgery on March 18, 2020-were compared with a 2019 control data set. RESULTS: During this time, OHNS at the general adult and pediatric medical centers and CCC experienced 87.8%, 77.1%, and 32% decreases in surgical procedures as compared with 2019, respectively. Aerosol-generating procedures accounted for 86.8% of general adult cases, 92.4% of pediatric cases, and 62.0% of CCC cases. Preoperative COVID-19 testing occurred in 7.1% of general adult, 9% of pediatric, and 6.9% of CCC cases. The majority of procedures were tiers 3a and 3b per the Centers for Medicare & Medicaid Services. Aerosol-protective personal protective equipment (PPE) was worn in 28.6% of general adult, 90% of pediatric, and 15.5% of CCC cases. CONCLUSION: For OHNS, the majority of essential surgical cases remained high-risk aerosol-generating procedures. Preoperative COVID-19 testing and intraoperative PPE usage were initially inconsistent; systemwide guidelines were developed rapidly but lagged behind recommendations of the OHNS department and its academy. OHNS best practice standards are needed for preoperative COVID-19 status screening and PPE usage as we begin national reopening.

Determining the utility of standard hospital microbiology testing: Comparing standard microbiology cultures with DNA sequence analysis in patients with chronic sinusitis.

OBJECTIVE: To demonstrate DNA sequencing analysis (DNAsa) of sinus cultures in patients with CRS is a reliable method of detecting pathogens in polymicrobial CRS infections. METHODS: After obtaining Institutional Review Board approval for this prospective cohort study, we selected a random sample of 50 patients with CRS at Medstar Georgetown University Hospital between September 2016 and March 2017. We defined CRS as a history of rhinosinusitis refractory to maximal medical therapy and prior endoscopic sinus surgery. Patients demonstrating active purulence in a sinus cavity were prospectively selected to undergo standard hospital cultures (SHC) and DNAsa cultures. Organisms identified in both methods were compared for each patient. RESULTS: Specimens were obtained from 29 female and 16 male patients with a mean age of 50 years. A total of 45 cultures were included in our final analysis; five cultures were excluded after inappropriate laboratory processing. Results from these patients were compared and analyzed. Cohen's weighted kappa analysis showed agreement between the two testing methods in identifying predominant microorganisms. DNAsa detected 31.9% more microorganisms compared to SHC (P < 0.05). When multiple microorganisms were detected, DNAsa yielded more positive results compared to SHC (P < 0.05). CONCLUSIONS: DNAsa detects all microorganisms identified by SHC as well as predominant microorganisms not detected by SHC. Thus molecular pathogen identification may be more reliable for identifying multiple microorganisms as compared to standard culture techniques that identify only one or two microorganisms. In recalcitrant cases of CRS, DNAsa may provide better guidance in selection of appropriate antimicrobial treatment.

Chromatin-associated APC regulates gene expression in collaboration with canonical WNT signaling and AP-1.

Mutation of the APC gene occurs in a high percentage of colorectal tumors and is a central event driving tumor initiation in the large intestine. The APC protein performs multiple tumor suppressor functions including negative regulation of the canonical WNT signaling pathway by both cytoplasmic and nuclear mechanisms. Published reports that APC interacts with ß-catenin in the chromatin fraction to repress WNT-activated targets have raised the possibility that chromatin-associated APC participates more broadly in mechanisms of transcriptional control. This screening study has used chromatin immunoprecipitation and next-generation sequencing to identify APC-associated genomic regions in colon cancer cell lines. Initial target selection was performed by comparison and statistical analysis of 3,985 genomic regions associated with the APC protein to whole transcriptome sequencing data from APC-deficient and APC-wild-type colon cancer cells, and two types of murine colon adenomas characterized by activated Wnt signaling. 289 transcripts altered in expression following APC loss in human cells were linked to APC-associated genomic regions. High-confidence targets additionally validated in mouse adenomas included 16 increased and 9 decreased in expression following APC loss, indicating that chromatin-associated APC may antagonize canonical WNT signaling at both WNT-activated and WNT-repressed targets. Motif analysis and comparison to ChIP-seq datasets for other transcription factors identified a prevalence of binding sites for the TCF7L2 and AP-1 transcription factors in APC-associated genomic regions. Our results indicate that canonical WNT signaling can collaborate with or antagonize the AP-1 transcription factor to fine-tune the expression of shared target genes in the colorectal epithelium. Future therapeutic strategies for APC-deficient colorectal cancers might be expanded to include agents targeting the AP-1 pathway.