Recognition of Salmonella by Dectin-1 induces presentation of peptide antigen to type B T cells.

Type B T cells recognize peptide-MHC class II (pMHCII) isoforms that are structurally distinct from those recognized by conventional type A T cells. These alternative type B conformers result from peptide loading in the absence of HLA-DM. Type A conformers are more stable than type B pMHCII conformers but bind the same peptide in the same register. Here, we show that interaction of Salmonella Typhimurium with bone marrow derived dendritic cells (BMDCs) isolated from C3H/HeNCr1 mice results in enhanced presentation of peptide Ag to type B T cells. The effect could be mimicked by purified PAMPs, the most potent of which were curdlan and zymosan, ß-(1,3)-glucan-containing polymers that are recognized by Dectin-1. Blocking of Dectin-1 with Ab and laminarin inhibited the induction of the type B T-cell response by BMDCs, confirming its role as a PRR for S. Typhimurium. Splenic DCs (sDCs) expressed Dectin-1 but were refractive to the induction of type B responses by S. Typhimurium and curdlan. Type B T cells have been shown to escape thymic tolerance and to transfer pathology in an autoimmune disease model. The induction of type B responses by gram-negative bacteria provides a mechanism by which autoreactive T cells may be produced during infection.

Intractable Aspiration Treated With Laryngectomy After SLAD-R Surgery: A Case Report.

A variety of surgical treatment options exist for adductor spasmodic dysphonia (ADSD) with selective adductor recurrent laryngeal nerve denervation and reinnervation (SLAD-R) being one of the more popular. We present a case of bilateral vocal fold paralysis (BVFP) for SLAD-R resulting in the need for total laryngectomy. We suggest BVFP is more common than reported and that we all must insure optimal long term follow up of our surgical patients. Laryngoscope, 2024.

Esophageal Liposarcoma: A Case Report and Review of the Literature.

Liposarcomas are extremely rare occurrences in the esophagus. Here, we present an unusual case of esophageal liposarcoma that contributed to a long history of dysphagia before a definitive diagnosis was reached. The case is that of a 61-year-old woman who complained of dysphagia and foreign body sensation in her throat and was found to have a large filling defect within the cervical esophagus on barium esophagogram. She underwent endoscopic resection of the mass and was diagnosed with a five-centimeter long, well-differentiated esophageal liposarcoma, confirmed with fluorescence in situ hybridization for MDM2 gene locus amplification. Subsequent laser ablation of the tumor bed was conducted with no recurrences noted to date. Proper histologic identification, alongside adjunctive cytogenetic and molecular diagnostics, followed by definitive surgical resection and extended follow-up, are emphasized as critical in optimizing outcomes for this disease. A review of the existing English-language medical literature relating to esophageal liposarcoma was performed and summarized.

Developing an Artificial Intelligence Tool to Predict Vocal Cord Pathology in Primary Care Settings.

OBJECTIVES: Diagnostic tools for voice disorders are lacking for primary care physicians. Artificial intelligence (AI) tools may add to the armamentarium for physicians, decreasing the time to diagnosis and limiting the burden of dysphonia. METHODS: Voice recordings of patients were collected from 2019 to 2021 using smartphones. The Saarbruecken dataset was included for comparison. Audio files were converted to mel-spectrograms using TensorFlow. Diagnostic categories were created to group pathology, including neurological and muscular disorders, inflammatory, mass lesions, and normal. The samples were further separated into sustained/a/and the rainbow passage. RESULTS: Two hundred three prospective samples and 1131 samples were used from the Saarbruecken database. The AI detected abnormal pathology with an F1-score of 98%. The artificial neural network (ANN) differentiated key pathologies, including unilateral paralysis, laryngitis, adductor spasmodic dysphonia (ADSD), mass lesions, and normal samples with 39%-87% F-1 scores. The Calgary database models had higher F-1 scores in a head-to-head comparison to the Saarbruecken and combined datasets (87% vs. 58% and 50%). The AI outperformed otolaryngologists using a standardized test set of recordings (83% compared to 55% ± 15%). CONCLUSION: An AI tool was created to differentiate pathology by individual or categorical diagnosis with high evaluation metrics. Prospective data should be collected in a controlled fashion to reduce intrinsic variability between recordings. Multi-center data collaborations are imperative to increase the prediction capability of AI tools for detecting vocal cord pathology. We provide proof-of-concept for an AI tool to assist primary care physicians in managing dysphonic patients. LEVEL OF EVIDENCE: 3 Laryngoscope, 133:1952-1960, 2023.

Long-Term Voice Outcomes Following Cricotracheal Resection for Subglottic Stenosis: A Retrospective Analysis.

OBJECTIVES/HYPOTHESIS: Cricotracheal resection (CTR) is an effective treatment for refractory idiopathic subglottic stenosis (iSGS) but is associated with persistent dysphonia. Outcomes were measured longitudinally to characterize how patients' voices and self-perceived voice handicaps changed after CTR. STUDY DESIGN: Retrospective case-series. METHODS: We conducted a retrospective cohort study of patients with refractory iSGS treated by CTR from 2006 to 2017. Voice Handicap Index (VHI), Consensus Auditory-Perceptual Evaluation of Voice (CAPE-V), and acoustic analysis were prospectively collected preoperatively and postoperatively at 1, 3, 6, 12, and 24-month intervals. A linear mixed model was used to evaluate temporal change. RESULTS: Thirty-three patients (97% female) were included. VHI scores increased significantly from baseline preoperative score (27.2 ± 22.7) to a mean value of 44.3 ± 25.6 (P < .001) 1-month postoperatively but decreased below preoperative scores after 2 years (18.8 ± 11.9, P = .795). Mean fundamental frequency (F0) values in speech decreased significantly from 192.0 ± 24.9 Hz preoperatively to 167.1 ± 19.8 Hz at a 2-year follow-up (P = .002), with a nadir value at 1-month postoperatively (148.4 ± 20.5, P < .001). CAPE-V scores increased significantly from preoperative to 1-month postoperative (3.0 ± 2.3 vs. 21.9 ± 17.3, P < .001) but returned toward baseline values at 24 months after CTR (6.9 ± 4.8, P = .027). CAPE-V measurements postoperatively were correlated with VHI and F0 (Pearson coefficient = 0.54 (VHI), -0.46 (F0), P < .001). CONCLUSIONS: Following CTR, mean F0 values were significantly and consistently lower but did increase over time, correlating with patients' improving VHI and CAPE-V scores. VHI values indicate that patient's perception of their voice is not significantly impacted in long term. These results provide a framework to counsel patients about long term voice expectations. LEVEL OF EVIDENCE: 4 Laryngoscope, 132:1054-1060, 2022.

Assessment of a virtual reality temporal bone surgical simulator: a national face and content validity study.

BACKGROUND: Trainees in Otolaryngology-Head and Neck Surgery must gain proficiency in a variety of challenging temporal bone surgical techniques. Traditional teaching has relied on the use of cadavers; however, this method is resource-intensive and does not allow for repeated practice. Virtual reality surgical training is a growing field that is increasingly being adopted in Otolaryngology. CardinalSim is a virtual reality temporal bone surgical simulator that offers a high-quality, inexpensive adjunct to traditional teaching methods. The objective of this study was to establish the face and content validity of CardinalSim through a national study. METHODS: Otolaryngologists and resident trainees from across Canada were recruited to evaluate CardinalSim. Ethics approval and informed consent was obtained. A face and content validity questionnaire with questions categorized into 13 domains was distributed to participants following simulator use. Descriptive statistics were used to describe questionnaire results, and either Chi-square or Fishers exact tests were used to compare responses between junior residents, senior residents, and practising surgeons. RESULTS: Sixty-two participants from thirteen different Otolaryngology-Head and Neck Surgery programs were included in the study (32 practicing surgeons; 30 resident trainees). Face validity was achieved for 5 out of 7 domains, while content validity was achieved for 5 out of 6 domains. Significant differences between groups (p-value of < 0.05) were found for one face validity domain (realistic ergonomics, p = 0.002) and two content validity domains (teaching drilling technique, p = 0.011 and overall teaching utility, p = 0.006). The assessment scores, global rating scores, and overall attitudes towards CardinalSim, were universally positive. Open-ended questions identified limitations of the simulator. CONCLUSION: CardinalSim met acceptable criteria for face and content validity. This temporal bone virtual reality surgical simulation platform may enhance surgical training and be suitable for patient-specific surgical rehearsal for practicing Otolaryngologists.

Correction to: Assessment of a virtual reality temporal bone surgical simulator: a national face and content validity study.

Following publication of the original article [1], the authors identified incorrect ordering and incorrect files being used for Figs. 1, 2 and 3.

Assessing the role of virtual reality training in Canadian Otolaryngology-Head & Neck Residency Programs: a national survey of program directors and residents.

BACKGROUND: Given mounting pressure of work hour restrictions, resource constraints, and variability of clinical exposure, Otolaryngology-Head & Neck Surgery (OHNS) residency training has shifted away from the apprenticeship model to embrace the Royal College of Physicians and Surgeons of Canada's "Competence by Design" initiative. As a result, appraising both current and potential educational adjuncts has become increasingly important. In this investigation, a national needs assessment survey was performed to identify strengths, weaknesses, and future opportunities of the current training landscape. METHODS: An online survey was distributed to all thirteen Canadian OHNS post-graduate administrators for completion by program directors and residents from February to October in 2016. Prior to distribution, the survey was vetted for face validity by a group of staff Otolaryngologists and questions were modified accordingly. Quantitative analysis was performed on SPSS (IBM Corp., Chicago) with non-parametric, two-tailed Mann-Whitney U testing performed on scaled questions. RESULTS: Of the 68 responses, 11 of 13 (84.6%) of program directors and 57 of 168 (33.9%) residents responded to the survey. All 13 programs currently utilize cadaveric laboratory dissections. Associated challenges were ranked as specimen availability, faculty participation, insufficient space, and resident time constraints. 30.8% of programs currently utilize some form of virtual reality simulator, which 90.9% of program directors felt would be a fair and effective platform for evaluation. CONCLUSION: A discrepancy exists between the favourable attitudes of both residents and program directors towards virtual reality simulation and its actual adoption. For successful adoption to occur, the existing barriers to unconventional training must be addressed and the tangible benefits for competency based training will need to be explored.