16 results on '"Ramakrishnan, Vijay R."'
Search Results
2. Unraveling the role of the microbiome in chronic rhinosinusitis.
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Psaltis, Alkis J., Mackenzie, Brett Wagner, Cope, Emily K., and Ramakrishnan, Vijay R.
- Abstract
Chronic rhinosinusitis (CRS) is a complex, heterogenous condition that is likely associated with infectious and inflammatory causative factors. Renewed interest in the role that microbes play in this condition has stemmed from advancements in microbe identification and parallel research implicating the microbiome as having a role in other chronic inflammatory conditions. This clinical commentary provides a review of the current literature relevant to chronic rhinosinusitis. Particular focus is placed on factors specific to investigation of the sinonasal microbiome, evidence for the role of dysbiosis in the disease state, and influences that may affect the microbiome. Possible mechanisms of disease and therapeutic implications through microbial manipulation are also reviewed, as are deficiencies and limitations of the current body of research. [ABSTRACT FROM AUTHOR]
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- 2022
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3. Clinical Olfactory Working Group consensus statement on the treatment of postinfectious olfactory dysfunction.
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Addison, Alfred B., Wong, Billy, Ahmed, Tanzime, Macchi, Alberto, Konstantinidis, Iordanis, Huart, Caroline, Frasnelli, Johannes, Fjaeldstad, Alexander W., Ramakrishnan, Vijay R., Rombaux, Philippe, Whitcroft, Katherine L., Holbrook, Eric H., Poletti, Sophia C., Hsieh, Julien W., Landis, Basile N., Boardman, James, Welge-Lüssen, Antje, Maru, Devina, Hummel, Thomas, and Philpott, Carl M.
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Respiratory tract viruses are the second most common cause of olfactory dysfunction. As we learn more about the effects of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), with the recognition that olfactory dysfunction is a key symptom of this disease process, there is a greater need than ever for evidence-based management of postinfectious olfactory dysfunction (PIOD). Our aim was to provide an evidence-based practical guide to the management of PIOD (including post–coronavirus 2019 cases) for both primary care practitioners and hospital specialists. A systematic review of the treatment options available for the management of PIOD was performed. The written systematic review was then circulated among the members of the Clinical Olfactory Working Group for their perusal before roundtable expert discussion of the treatment options. The group also undertook a survey to determine their current clinical practice with regard to treatment of PIOD. The search resulted in 467 citations, of which 107 articles were fully reviewed and analyzed for eligibility; 40 citations fulfilled the inclusion criteria, 11 of which were randomized controlled trials. In total, 15 of the articles specifically looked at PIOD whereas the other 25 included other etiologies for olfactory dysfunction. The Clinical Olfactory Working Group members made an overwhelming recommendation for olfactory training; none recommended monocycline antibiotics. The diagnostic role of oral steroids was discussed; some group members were in favor of vitamin A drops. Further research is needed to confirm the place of other therapeutic options. [ABSTRACT FROM AUTHOR]
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- 2021
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4. Using fixed anatomical landmarks to avoid medial rectus injury: a radiographic analysis in patients with and without Graves' disease.
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Suh, Jeffrey D, Kuan, Edward C, Thompson, Christopher F, Scawn, Richard L, Feinstein, Aaron J, Barham, Henry P, Kingdom, Todd T, and Ramakrishnan, Vijay R
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Background: Injury to the medial rectus (MR) is a potentially devastating complication of orbital and sinus surgery. Precise knowledge of the MR relative to the lamina papyracea (LP) is important during endoscopic surgery for both Graves' ophthalmopathy and inflammatory disease. The objective of this study is to determine the location of the MR in relation to easily identified and frequently encountered intranasal landmarks in patients with and without Graves' disease.Methods: High-resolution computed tomography scans were analyzed in 100 controls and 63 patients with Graves' disease. The MR position was recorded relative to the maxillary sinus ostium (MSO), anterior ethmoid artery (AEA), and posterior ethmoid artery (PEA)/horizontal basal lamella (BL). Clinically relevant variables recorded at each level included the Keros stage, AEA position, MR height, and distance of the MR to orbital floor, skull base, and LP.Results: The mean distances between the MR and LP were statistically different for both groups. Controls at the MSO, AEA, and PEA/BL were 2.92, 1.69, and 1.06mm; for Graves' patients measurements at these sites were 2.12, 1.20, and 0.029mm. When comparing the two groups, each of these distances were statistically significant (p<0.02). There was no difference in ethmoid cavity width (p>0.05) between controls (9.66mm) and Graves' patients (9.70mm). Sex, age, and skull base depth were not statistically significant factors.Conclusion: This study illustrates the position of the MR from the perspective of an endoscopic surgeon utilizing fixed intranasal landmarks. Knowledge of the position of MR is critical to safely perform decompression surgery and when operating adjacent to the LP during endoscopic surgery. [ABSTRACT FROM AUTHOR]- Published
- 2016
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5. Microbiome in patients with upper airway disease: Moving from taxonomic findings to mechanisms and causality.
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Ramakrishnan, Vijay R. and Frank, Daniel N.
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- 2018
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6. Inflammatory molecular endotypes of nasal polyps derived from White and Japanese populations.
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Nakayama, Tsuguhisa, Lee, Ivan T., Le, Wei, Tsunemi, Yasuhiro, Borchard, Nicole A., Zarabanda, David, Dholakia, Sachi S., Gall, Philip A., Yang, Angela, Kim, Dayoung, Akutsu, Makoto, Kashiwagi, Takashi, Patel, Zara M., Hwang, Peter H., Frank, Daniel N., Haruna, Shin-ichi, Ramakrishnan, Vijay R., Nolan, Garry P., Jiang, Sizun, and Nayak, Jayakar V.
- Abstract
Emerging evidence suggests that chronic rhinosinusitis with nasal polyps (CRSwNP) is a highly heterogeneous disease with disparate inflammatory characteristics between different racial groups and geographies. Currently, little is known about possible underlying distinguishing factors between these inflammatory differences. Our aim was to interrogate differences in CRSwNP disease between White/non-Asian patients and Japanese patients by using whole transcriptome and single-cell RNA gene expression profiling of nasal polyps (NPs). We performed whole transcriptome RNA sequencing with endotype stratification of NPs from 8 White patients (residing in the United States) and 9 Japanese patients (residing in Japan). Reproducibility was confirmed by quantitative PCR in an independent validation set of 46 White and 31 Japanese patients. Single-cell RNA sequencing (scRNAseq) was used to stratify key cell types for contributory transcriptional signatures. Unsupervised clustering analysis identified 2 major endotypes that were present within both cohorts of patients with NPs and had previously been reported at the cytokine level: (1) type 2 endotype and (2) non–type 2 endotype. Importantly, there was a statistically significant difference in the proportion of these endotypes between these geographically distinct subgroups with NPs (P =.03). Droplet-based single-cell RNA sequencing further identified prominent type 2 inflammatory transcript expression: C-C motif chemokine ligand 13 (CCL13) and CCL18 in M2 macrophages, as well as cystatin SN (CST1) and CCL26 in basal, suprabasal, and secretory epithelial cells. NPs from both racial groups harbor the same 2 major endotypes, which we have determined to be present in differing ratios between each cohort with CRSwNP disease. Distinct inflammatory and epithelial cells contribute to the type 2 inflammatory profiles observed. [ABSTRACT FROM AUTHOR]
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- 2022
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7. Characterization and treatment of patients with chronic rhinosinusitis and nasal polyps.
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Fountain, Cynthia R, Mudd, Pamela A, Ramakrishnan, Vijay R, Sillau, Stefan H, Kingdom, Todd T, and Katial, Rohit K
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- 2013
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8. Endoscopic endonasal surgical resection of tumors of the medial orbital apex and wall
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Lee, John Y.K., Ramakrishnan, Vijay R., Chiu, Alexander G., Palmer, James, and Gausas, Roberta E.
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- 2012
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9. Endotyping chronic rhinosinusitis based on olfactory cleft mucus biomarkers.
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Soler, Zachary M., Schlosser, Rodney J., Bodner, Todd E., Alt, Jeremiah A., Ramakrishnan, Vijay R., Mattos, Jose L., Mulligan, Jennifer K., Mace, Jess C., and Smith, Timothy L.
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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. 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. 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. 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/T h 17-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, χ 18 2 = 178.64 ; P <.001). Olfactory measures differed significantly across clusters, including olfactory testing, QOD-NS, and OC endoscopy (P <.001 for all). 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. [ABSTRACT FROM AUTHOR]
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- 2021
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10. Revision endoscopic dacryocystorhinostomy.
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Ramakrishnan, Vijay R., Durairaj, Vikram D., and Kingdom, Todd T.
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Dacryocystorhinostomy (DCR) failures may occur after primary external or endoscopic approaches. Revision surgery is beneficial for many of these patients. Clinical experience suggests that endoscopic lacrimal surgery offers technical benefits over the traditional external approach that may aid in revision cases. Ultimately, the operative goals of revision endoscopic DCR are similar to that of primary surgery. Advancements in endoscopic technology and instrumentation have been helpful in achieving these procedural goals. This article describes the authors'' rationale and technique for revision endoscopic DCR. [Copyright &y& Elsevier]
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- 2008
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11. Preoperative ethmoid artery ligation facilitates resection of large sub-frontal meningiomas.
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Ung, Timothy H, Waziri, Allen E, and Ramakrishnan, Vijay R
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- 2014
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12. Altered tissue specialized pro-resolving mediators in chronic rhinosinusitis.
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Vickery, Thad W., Armstrong, Michael, Kofonow, Jennifer M., Robertson, Charles E., Kroehl, Miranda E., Reisdorph, Nichole A., Ramakrishnan, Vijay R., and Frank, Daniel N.
- Abstract
• Distinct lipidomic signatures in CRS offer new therapeutic targets for each subtype. • Pro-resolving mediators RvD2 and LXA 4 are elevated in CRSwNP compared to CRSsNP. • Sinonasal RVD1 and RvD2 are decreased in cigarette smokers compared with never-smokers. • Upper airway microbiota are associated with lipid mediators in underlying tissue. Current 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 A 4 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. [ABSTRACT FROM AUTHOR]
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- 2021
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13. Expression of immunoglobulin D is increased in chronic rhinosinusitis.
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Sokoya, Mofiyinfolu, Ramakrishnan, Vijay R., Frank, Daniel N., Rahkola, Jeremy, Getz, Anne, Kingdom, Todd T., Kofonow, Jennifer M., Nguyen, Quyen, and Janoff, Edward N.
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- 2017
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14. Sinus microbiota varies among chronic rhinosinusitis phenotypes and predicts surgical outcome.
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Ramakrishnan, Vijay R., Hauser, Leah J., Feazel, Leah M., Ir, Diana, Robertson, Charles E., and Frank, Daniel N.
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Background Chronic rhinosinusitis (CRS) is a prevalent multifactorial disease process in which bacteria are believed to play a role in the propagation of inflammation. Multiple subtypes of CRS have been described based on clinical and pathologic features, but a detailed examination of the sinus microbiota in patients with CRS and its clinical subtypes has yet to be performed. Objective We sought to examine the resident microbiota of CRS subtypes and determine whether bacterial diversity is a predictor of disease outcomes. Methods Sinus swabs from patients with CRS and healthy subjects collected during endoscopic sinus surgery were analyzed by means of molecular phylogenetic analysis of 16S rDNA pyrosequences. Results Fifty-six patients with CRS and 26 control subjects were studied. Biodiversity was similar between the CRS and control groups. Among the CRS subtypes examined, only 2 conditions (presence of purulence and comorbid condition of asthma) were associated with significant alterations in microbial community composition. In 27 patients with CRS who were followed postoperatively, those with better outcomes had more diverse bacterial communities present at the time of surgery, along with higher relative abundances of Actinobacteria. Conclusion Analysis of microbiota in a large cohort reveals that particular CRS phenotypes (asthma and purulence) are characterized by distinct compositions of resident bacterial communities. We found that bacterial diversity and composition are predictors of surgical outcome, promoting the concept of community ecology in patients with CRS. [ABSTRACT FROM AUTHOR]
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- 2015
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15. Parapharyngeal and skull base yolk sac tumor: A case report with lessons in diagnosis and management.
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Hauser, Leah J., Chiang, Tendy, Ramakrishnan, Vijay R., Lovell, Mark A., and Kelley, Peggy E.
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SKULL base , *ENDODERMAL sinus tumors , *CANCER chemotherapy , *ENDOSCOPY , *PEDIATRICS , *OTOLARYNGOLOGY - Abstract
Yolk sac tumors are rare in the head and neck. A previously healthy 2-year-old female presented with a large parapharyngeal mass. Pathology was pathognomonic for yolk sac tumor, with glandular differentiation and focal mucin production, which has not been reported in a yolk sac tumor. She was treated aggressively with chemotherapy followed by endoscopic exploration with planned resection, but no viable tumor was encountered. Yolk sac tumors can be difficult to diagnose in the head and neck, but complete clinical response can be achieved. New endoscopic approaches to skull base tumors are applicable to the pediatric population with some technical modifications. [ABSTRACT FROM AUTHOR]
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- 2014
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16. The Effect of Preoperative Direct Ligation of Ethmoidal Arteries on the Perioperative Outcomes of Large Anterior Skull Base Meningiomas Surgery: A Clinical Study.
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Aref, Mohammed, Kunigelis, Katherine E., Yang, Alexander, Subramanian, Prem S., Ramakrishnan, Vijay R., and Youssef, A. Samy
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PREOPERATIVE care , *ETHMOID bone , *MENINGIOMA , *BRAIN tumors , *OPERATIVE surgery - Abstract
Background Anterior skull base meningiomas often grow to a large size (≥4 cm) before detection. Their blood supply is mostly provided by the anterior and posterior ethmoidal arteries. Because of their vascularity, intraoperative bleeding can be a challenging prospect that increases the risk of perioperative complications. Preoperative ethmoidal arteries ligation has been used to aid in limiting blood loss. Our objective was to assess the effect of preoperative arterial ligation on the perioperative course of large (≥4 cm) to giant (≥6 cm) anterior skull base meningiomas. Methods We retrospectively searched our database for large anterior skull base meningiomas (≥4 cm). We analyzed differences in intraoperative blood loss, operative time, intraoperative transfusion, and hematologic parameters between patients who did not undergo preoperative ethmoidal arteries ligation (Group 1) and those who did (Group 2). Results Average estimated blood loss (EBL) was 825 mL (Group 1) versus 350 mL (Group 2) (P = 0.42), decrease in hemoglobin was 4 g/dL versus 3.2 g/dL (P = 0.53), decrease in hematocrit was 12.4% versus 9.6% (P = 0.64), and average operative time was 656 minutes versus 598 minutes (P = 0.58). EBL per volume yielded a ratio of 10.6 mL/cm3 versus 4.1 mL/cm3 (P = 0.06). Conclusions Ethmoidal arteries ligation may have a benefit in large-to-giant anterior skull base meningiomas surgery. Our results showed a decrease in EBL and lesser decrease in pre- and postoperative hemoglobin and hematocrit levels as compared with cases in which no vascular ligation was performed when corrected for tumor volume. Highlights • Due to their subtle symptoms, subfrontal meningiomas tend to grow to a large size before being discovered. • Meningiomas are highly vascular lesions and hence, large meningiomas have a risk of high-volume blood loss. • The anterior followed by posterior ethmoidal arteries are the main blood supply of subfrontal meningiomas. • Preoperative ligation of ethmoidal arteries has been proposed as a method of limiting intraoperative blood loss. • Preoperative ligation of ethmoidal arteries decreases intraoperative blood loss; this was not statistically significant. [ABSTRACT FROM AUTHOR]
- Published
- 2018
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