Browsing by Author "Ramakrishnan, Vijay R."
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Item A Dysbiotic Microbiome Promotes Head and Neck Squamous Cell Carcinoma(Springer Nature, 2022) Frank, Daniel N.; Qiu, Yue; Cao, Yu; Zhang, Shuguang; Lu, Ling; Kofonow, Jennifer M.; Robertson, Charles E.; Liu, Yanqiu; Wang, Haibo; Levens, Cassandra L.; Kuhn, Kristi A.; Song, John; Ramakrishnan, Vijay R.; Lu, Shi-Long; Otolaryngology -- Head and Neck Surgery, School of MedicineRecent studies have reported dysbiotic oral microbiota and tumor-resident bacteria in human head and neck squamous cell carcinoma (HNSCC). We aimed to identify and validate oral microbial signatures in treatment-naïve HNSCC patients compared with healthy control subjects. We confirm earlier reports that the relative abundances of Lactobacillus spp. and Neisseria spp. are elevated and diminished, respectively, in human HNSCC. In parallel, we examined the disease-modifying effects of microbiota in HNSCC, through both antibiotic depletion of microbiota in an induced HNSCC mouse model (4-Nitroquinoline 1-oxide, 4NQO) and reconstitution of tumor-associated microbiota in a germ-free orthotopic mouse model. We demonstrate that depletion of microbiota delays oral tumorigenesis, while microbiota transfer from mice with oral cancer accelerates tumorigenesis. Enrichment of Lactobacillus spp. was also observed in murine HNSCC, and activation of the aryl-hydrocarbon receptor was documented in both murine and human tumors. Together, our findings support the hypothesis that dysbiosis promotes HNSCC development.Item Altered Tissue Specialized Pro-Resolving Mediators in Chronic Rhinosinusitis(Elsevier, 2021) Vickery, Thad W.; Armstrong, Michael; Kofonow, Jennifer M.; Robertson, Charles E.; Kroehl, Miranda E.; Reisdorph, Nichole A.; Ramakrishnan, Vijay R.; Frank, Daniel N.; Otolaryngology -- Head and Neck Surgery, School of MedicineCurrent literature implicates arachidonic acid-derived leukotrienes and prostaglandins in the pathogenesis of chronic rhinosinusitis. However, other omega-3 and omega-6 derived lipid mediators, such as specialized pro-resolving mediators (SPMs), may also be important in chronic inflammatory disorders of the upper airway. We hypothesize that SPMs differ among CRS subtypes compared to controls and in relation to sinonasal microbiota. Ethmoid sinus tissue and middle meatal swabs were collected from a convenience sample of 66 subjects, including non-CRS controls, CRS with polyps (CRSwNP), and CRS without polyps (CRSsNP). Lipid mediator pathways were analyzed by liquid chromatography/tandem mass spectrometry. Bacterial taxa were profiled in parallel by 16S rRNA gene sequencing. Resolvin D2 was elevated in both CRSwNP (p = 0.00076) and CRSsNP (p = 0.030) compared with non-CRS controls. Lipoxin A4 was significantly increased in CRSwNP compared with CRSsNP (p = 0.000033) and controls (p = 0.044). Cigarette smoking was associated with significantly lower concentrations of several 15-lipoxygenase metabolites including resolvin D1 (p = 0.0091) and resolvin D2 (p = 0.0097), compared with never-smokers. Several of the lipid compounds also correlated with components of the sinonasal mucosal microbiota, including bacterial pathogens such as Pseudomonas aeruginosa. These data suggest that dysfunctional lipid mediator pathways in CRS extend beyond the traditional descriptions of leukotrienes and prostaglandins and include SPMs. Furthermore, dysregulated SPM signaling may contribute to persistent inflammation and bacterial colonization in CRS.Item Cumulative Comorbidity Burden Does Not Worsen Outcomes in Management of Chronic Rhinosinusitis(Wiley, 2022) Gill, Amarbir S.; Mace, Jess C.; Rimmer, Ryan; Ramakrishnan, Vijay R.; Beswick, Daniel M.; Soler, Zachary M.; Manor, James; Orlandi, Richard R.; Smith, Timothy L.; Alt, Jeremiah A.; Otolaryngology -- Head and Neck Surgery, School of MedicineBackground: The impact of multiple coexisting medical comorbidities on treatment outcomes in chronic rhinosinusitis (CRS) is unknown. In this study we sought to evaluate the effect of comorbidities on sinonasal quality of life (QOL) and general health utility values by utilizing the Functional Comorbidity Index (FCI) in CRS patients. Methods: Patients with CRS were prospectively enrolled in a cross-sectional study of medical and surgical therapies. The 22-item Sino-Nasal Outcome Test (SNOT-22) and Medical Outcomes Study Short-Form 6D (SF-6D) scores were recorded at enrollment and 6-month follow-up; Lund-Kennedy endoscopy and Lund-Mackay computed tomography scores were recorded at enrollment. The FCI was calculated using the electronic medical record. The impact of cumulative comorbidity burden on baseline and posttreatment outcomes was assessed using univariate and bivariate correlations. Results: A total of 428 participants with CRS were included. The average (mean standard ± deviation) FCI score was 3.03 ± 2.28 (range, 0-12). Significant linear correlations were identified between increasing FCI score and baseline SNOT-22 and SF-6D scores (R = 0.166, p = 0.001 and R = -0.245, p < 0.001, respectively). There was no correlation between FCI and change in SNOT-22 or SF-6D scores after CRS treatment (R = 0.066, p = 0.17 and R = -0.087, p = 0.074, respectively). Achievement of a minimally clinically important difference was also independent of FCI. Conclusion: Although cumulative comorbidity burden, as measured by FCI, is associated with worse baseline SNOT-22 and SF-6D scores, it does not appear to limit posttreatment improvement in either outcome measure. On average, patients with high comorbidity burden report substantial improvement in both QOL and health utility after CRS treatment, similar to those with fewer comorbidities.Item Disease control after surgery for chronic rhinosinusitis: Prospective, multi-institutional validation of the Sinus Control Test (SCT)(Wiley, 2021) Little, Ryan E.; Schlosser, Rodney J.; Smith, Timothy L.; Storck, Kristina A.; Alt, Jeremiah A.; Beswick, Daniel M.; Mace, Jess C.; Mattos, Jose L.; Ramakrishnan, Vijay R.; Soler, Zachary M.; Otolaryngology -- Head and Neck Surgery, School of MedicineBackground: The Sinus Control Test (SCT) is a 4-question, patient-reported questionnaire that assesses disease control in chronic rhinosinusitis (CRS). This prospective, multicenter study examines SCT outcomes following endoscopic sinus surgery (ESS), further validating its use as a control instrument for CRS. Methods: Adults with CRS undergoing ESS were prospectively enrolled from 5 centers across North America. The SCT was administered at baseline and once 6 months after surgery. Quality of life and disease burden were evaluated using the 22-item Sino-Nasal Outcome Test (SNOT-22) and Lund-Kennedy endoscopy scores. Linear regression was used to determine whether specific demographic, comorbidity, or disease severity measures were independently associated with changes in SCT scores postoperatively. Results: A total of 218 patients, 111 females (50.9%) and 107 males (49.1%), were enrolled, with mean ± standard deviation age of 50.1 ± 15.6 years. Mean SCT score improved from 8.9 ± 3.5 to 4.3 ± 3.7 postoperatively (p < 0.001). Preoperatively, 21.6% were uncontrolled, 71.5% partially controlled, and 6.9% controlled. Postoperatively, 6.0% were uncontrolled, 42.6% partially controlled, and 51.4% controlled (p < 0.001). Change in SCT score correlated independently with change in SNOT-22 (r = 0.500, p < 0.001) and endoscopy scores (r = 0.310, p < 0.001). Endoscopy scores did not correlate with control status among patients with CRS without nasal polyposis (CRSsNP) nor between uncontrolled and partially controlled patients. Demographics and comorbidities were not associated with changes in SCT. Conclusion: Improvement in disease control following ESS as measured by the SCT correlated with improvements in SNOT-22 and endoscopy scores. The SCT is an easily administered instrument that provides information complementary to existing patient-reported and objective measures of disease severity.Item Endotyping Chronic Rhinosinusitis Based on Olfactory Cleft Mucus Biomarkers(Elsevier, 2021) Soler, Zachary M.; Schlosser, Rodney J.; Bodner, Todd E.; Alt, Jeremiah A.; Ramakrishnan, Vijay R.; Mattos, Jose L.; Mulligan, Jennifer K.; Mace, Jess C.; Smith, Timothy L.; Otolaryngology -- Head and Neck Surgery, School of MedicineBackground: Although chronic rhinosinusitis (CRS) is considered the most treatable form of olfactory dysfunction, there has been relatively little clinical attention focused on assessing endotypes as they pertain to olfactory loss. Objectives: The goal of this study was to explore inflammatory endotypes in CRS using an unsupervised cluster analysis of olfactory cleft (OC) biomarkers in a phenotype-free approach. Methods: Patients with CRS were prospectively recruited and psychophysical olfactory testing, Questionnaire of Olfactory Dysfunction (QOD-NS), and bilateral OC endoscopy were obtained. Mucus was collected from the OC and evaluated for 26 biomarkers using principal component analysis. Cluster analysis was performed using only OC biomarkers and differences in olfactory measures were compared across clusters. Results: A total of 198 subjects (128 with CRS and 70 controls) were evaluated. Evaluation of OC biomarkers indicated 6 principal components, explaining 69.50% of the variance, with type 2, mixed type 1/Th17-cell, growth factor, and neutrophil chemoattractant inflammatory signatures. A total of 10 clusters were identified that differed significantly in frequency of controls, and subjects with CRS with nasal polyps, and subjects with CRS without nasal polyps across the clusters (likelihood ratio test, χ182=178.64; P < .001). Olfactory measures differed significantly across clusters, including olfactory testing, QOD-NS, and OC endoscopy (P < .001 for all). Conclusions: Clustering based solely on OC biomarkers can organize patients into clinically meaningful endotypes that discriminate between subjects with CRS and controls. Validation studies are necessary to confirm these findings and further refine olfactory endotypes.Item Ethmoid-to-Maxillary Opacification Ratio: A Predictor of Postoperative Olfaction and Outcomes in Nasal Polyposis?(Wiley, 2021) Beswick, Daniel M.; Smith, Timothy L.; Mace, Jess C.; Alt, Jeremiah A.; Farrell, Nyssa F.; Ramakrishnan, Vijay R.; Schlosser, Rodney J.; Soler, Zachary; Otolaryngology -- Head and Neck Surgery, School of MedicineBackground: Inflammatory profiles for patients with chronic rhinosinusitis with nasal polyposis (CRSwNP) vary between North American and Asian populations. An elevated ethmoid-to-maxillary (E/M) opacification ratio on preoperative imaging is associated with certain postoperative outcomes in Asian populations and populations that are non-type 2 dominant. In this study we explore this factor in North American/type 2-based populations. Methods: Adult patients (n = 165) from a North American population with CRSwNP who underwent endoscopic sinus surgery (ESS) were prospectively enrolled into an observational, multi-institutional study. The 22-item Sino-Nasal Outcome Test (SNOT-22), Brief Smell Identification Test (BSIT), and Lund-Kennedy (LK) endoscopic scores were obtained pre- and postoperatively. Patients were stratified according to increasing E/M ratios based on Lund-Mackay (LM) scores. Results: On average, significant within-subject postoperative improvement was found in all patients for SNOT-22 total and domain scores, and also BSIT results (p ≤ 0.019). Preoperatively, elevated E/M ratio correlated with worse BSIT scores (r = -0.343, p < 0.001). Postoperatively, elevated E/M ratio correlated with BSIT improvement (r = 0.284, p = 0.002), but did not correlate with SNOT-22 improvement or polyp recurrence. An elevated E/M ratio was associated with greater likelihood of reporting a minimal clinically important difference in BSIT scores (χ2 = 9.96, p = 0.041). Conclusion: Elevated E/M ratios were found to associated with worse baseline olfaction and an increased likelihood of achieving a clinically meaningful postoperative improvement in olfaction in this North American population with CRSwNP. Elevated E/M ratios did not predict postoperative changes in SNOT-22 measures or polyp recurrence. This suggests that prognostic factors may vary according to geography and generalized inflammatory profiles (type 2 vs non-type 2) in patients with CRS.Item Evaluating Distance Bias in Chronic Rhinosinusitis Outcomes(American Medical Association, 2022) Gill, Amarbir S.; Beswick, Daniel M.; Mace, Jess C.; Menjivar, Dennis; Ashby, Shaelene; Rimmer, Ryan A.; Ramakrishnan, Vijay R.; Soler, Zachary M.; Alt, Jeremiah A.; Otolaryngology -- Head and Neck Surgery, School of MedicineImportance: The distance traveled by patients for medical care is associated with patient outcomes (ie, distance bias) and is a limitation in outcomes research. However, to date, distance bias has not been examined in rhinologic studies. Objective: To evaluate the association of distance traveled by a cohort of patients with chronic rhinosinusitis with baseline disease severity and treatment outcomes. Design, setting, and participants: A total of 505 patients with chronic rhinosinusitis were prospectively enrolled in a multi-institutional, cross-sectional study in academic tertiary care centers between April 2011 and January 2020. Participants self-selected continued appropriate medical therapy or endoscopic sinus surgery. The 22-item Sinonasal Outcome Test (SNOT-22) and Medical Outcomes Study Short Form 6-D (SF-6D) health utility value scores were recorded at enrollment and follow-up. Data on the distances traveled by patients to the medical centers, based on residence zip codes, and medical comorbid conditions were collected. Exposures: Distance traveled by patient to obtain rhinologic care. Main outcomes and measures: SNOT-22 and SF-6D scores. Scores for SNOT-22 range from 0 to 110; and for SF-6D, from 0.0 to 1.0. Higher SNOT-22 total scores indicate worse overall symptom severity. Higher SF-6D scores indicate better overall health utility; 1.0 represents perfect health and 0.0 represents death. Results: The median age for the 505 participants was 56.0 years (IQR, 41.0-64.0 years), 261 were men (51.7%), 457 were White (90.5%), and 13 were Hispanic or Latino (2.6%). These categories were collected according to criteria described and required by the National Institutes of Health and therefore do not equal the entire cohort. Patients traveled a median distance of 31.6 miles (50.6 km) (IQR, 12.2-114.5 miles [19.5-183.2 km]). Baseline (r = 0.00; 95% CI, 0.00-0.18) and posttreatment (r = 0.01; 95% CI, -0.07 to 0.10) SNOT-22 scores, as well as baseline (r = -0.12; 95% CI, -0.21 to -0.04) and posttreatment (r = 0.07; 95% CI, -0.02 to 0.16) SF-6D scores, were not associated with distance. There was no clinically meaningful correlation between distance traveled and mean comorbidity burden. Nevertheless, patients with a history of endoscopic sinus surgery were more likely to travel longer distances to obtain care (Cliff delta = 0.28; 95% CI, 0.19-0.38). Conclusions and relevance: Although this cross-sectional study found that some patients appear more willing to travel longer distances for chronic rhinosinusitis care, results suggest that distance traveled to academic tertiary care centers was not associated with disease severity, outcomes, or comorbidity burden. These findings argue for greater generalizability of study results across various cohorts independent of distance traveled to obtain rhinologic care.Item High-Riding Innominate Artery: Booby Trap for ICU Tracheotomy(Wiley, 2025) Ramakrishnan, Vijay R.; Kaefer, Samuel L.; Otolaryngology -- Head and Neck Surgery, School of MedicineDespite tracheotomy being a routine procedure, it is not rare to encounter anatomic irregularities that can compromise its success. In this report, we describe a case in which a high riding innominate artery was identified within the surgical trajectory moments before incision, which ultimately necessitated airway securement using an alternative laryngological procedure.Item Infection and inflammation in chronic rhinosinusitis: Gene ontology/pathway analysis perspective(Wiley, 2022) Ramakrishnan, Vijay R.; Larson, Eric; Holt, Justin; Frank, Daniel N.; Otolaryngology -- Head and Neck Surgery, School of MedicineItem Inflammation resolution and specialized pro-resolving lipid mediators in chronic rhinosinusitis(Taylor & Francis, 2023) Robinson, Peyton Z.; Frank, Daniel N.; Ramakrishnan, Vijay R.; Otolaryngology -- Head and Neck Surgery, School of MedicineIntroduction: In chronic rhinosinusitis (CRS), a complex pathophysiology results from varied pro-inflammatory stimuli but is consistently characterized by classic cellular, molecular, and microbial alterations. Normally, endogenous specialized pro-resolving mediators (SPM) actively promote resolution of inflammation through numerous pathways, including those involved in host antimicrobial defense. However, these pathways appear to be disrupted in CRS. Areas covered: This paper describes features of CRS in the context of chronic tissue inflammation, and potential mechanisms by which specialized pro-resolving mediators promote active resolution of tissue inflammation. Expert opinion: Temporal phases of resolution must be tightly regulated to successfully resolve inflammation in CRS while preserving tissue functions such as barrier maintenance and special sensory function. Dysregulation of SPM enzymatic pathways has been recently shown in CRS and is associated with disease phenotypes and microbial colonization patterns. Current research in animal models and in vitro human cell culture, as well as human dietary studies, demonstrate relevant changes in cell signaling with lipid mediator bioavailability. Further clinical research may provide insight into the therapeutic value of this approach in CRS.