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Kikuta S, Nagayama S, Hasegawa-Ishii S. Structures and functions of the normal and injured human olfactory epithelium. Front Neural Circuits 2024; 18:1406218. [PMID: 38903957 PMCID: PMC11188711 DOI: 10.3389/fncir.2024.1406218] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2024] [Accepted: 05/20/2024] [Indexed: 06/22/2024] Open
Abstract
The olfactory epithelium (OE) is directly exposed to environmental agents entering the nasal cavity, leaving OSNs prone to injury and degeneration. The causes of olfactory dysfunction are diverse and include head trauma, neurodegenerative diseases, and aging, but the main causes are chronic rhinosinusitis (CRS) and viral infections. In CRS and viral infections, reduced airflow due to local inflammation, inflammatory cytokine production, release of degranulated proteins from eosinophils, and cell injury lead to decreased olfactory function. It is well known that injury-induced loss of mature OSNs in the adult OE causes massive regeneration of new OSNs within a few months through the proliferation and differentiation of progenitor basal cells that are subsequently incorporated into olfactory neural circuits. Although normal olfactory function returns after injury in most cases, prolonged olfactory impairment and lack of improvement in olfactory function in some cases poses a major clinical problem. Persistent inflammation or severe injury in the OE results in morphological changes in the OE and respiratory epithelium and decreases the number of mature OSNs, resulting in irreversible loss of olfactory function. In this review, we discuss the histological structure and distribution of the human OE, and the pathogenesis of olfactory dysfunction associated with CRS and viral infection.
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Affiliation(s)
- Shu Kikuta
- Department of Otolaryngology-Head and Neck Surgery, Faculty of Medicine, Nihon University, Tokyo, Japan
| | - Shin Nagayama
- Department of Neurobiology and Anatomy, McGovern Medical School at The University of Texas Health Science Center at Houston, Houston, TX, United States
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2
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Root ZT, Schneller AR, Lepley TJ, Wu Z, Zhao K. Computational Fluid Dynamics and Its Potential Applications for the ENT Clinician. Facial Plast Surg 2024; 40:323-330. [PMID: 38224693 DOI: 10.1055/s-0043-1778072] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2024] Open
Abstract
This article is an examination of computational fluid dynamics in the field of otolaryngology, specifically rhinology. The historical development and subsequent application of computational fluid dynamics continues to enhance our understanding of various sinonasal conditions and surgical planning in the field today. This article aims to provide a description of computational fluid dynamics, the methods for its application, and the clinical relevance of its results. Consideration of recent research and data in computational fluid dynamics demonstrates its use in nonhistological disease pathology exploration, accompanied by a large potential for surgical guidance applications. Additionally, this article defines in lay terms the variables analyzed in the computational fluid dynamic process, including velocity, wall shear stress, area, resistance, and heat flux.
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Affiliation(s)
- Zachary T Root
- Department of Otolaryngology - Head & Neck Surgery, The Ohio State University, Columbus, Ohio
| | - Aspen R Schneller
- Department of Otolaryngology - Head & Neck Surgery, The Ohio State University, Columbus, Ohio
| | - Thomas J Lepley
- Department of Otolaryngology - Head & Neck Surgery, The Ohio State University, Columbus, Ohio
| | - Zhenxing Wu
- Department of Otolaryngology - Head & Neck Surgery, The Ohio State University, Columbus, Ohio
| | - Kai Zhao
- Department of Otolaryngology - Head & Neck Surgery, The Ohio State University, Columbus, Ohio
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3
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Yu P, Chen W, Jiang L, Jia Y, Xu X, Shen W, Jin N, Du H. Olfactory dysfunction and the role of stem cells in the regeneration of olfactory neurons. Heliyon 2024; 10:e29948. [PMID: 38694081 PMCID: PMC11058886 DOI: 10.1016/j.heliyon.2024.e29948] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2023] [Revised: 04/08/2024] [Accepted: 04/17/2024] [Indexed: 05/03/2024] Open
Abstract
The prevalence of COVID-19 has drawn increasing attention to olfactory dysfunction among researchers. Olfactory dysfunction manifests in various clinical types, influenced by numerous pathogenic factors. Despite this diversity, the underlying pathogenesis remains largely elusive, contributing to a lack of standardized treatment approaches. However, the potential regeneration of olfactory neurons within the nasal cavity presents a promising avenue for addressing olfactory dysfunction effectively. Our review aims to delve into the current research landscape and treatment modalities concerning olfactory dysfunction, emphasizing etiology, pathogenesis, clinical interventions, and the role of stem cells in regenerating olfactory nerves. Through this comprehensive examination, we aim to provide valuable insights into understanding the onset, progression, and treatment of olfactory dysfunction diseases.
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Affiliation(s)
- Pengju Yu
- Department of Otolaryngology, Traditional Chinese Medicine Hospital of Kunshan, Jiangsu Province, China
| | - Weiguan Chen
- Operating Room, Traditional Chinese Medicine Hospital of Kunshan, Jiangsu Province, China
| | - Ling Jiang
- Operating Room, Traditional Chinese Medicine Hospital of Kunshan, Jiangsu Province, China
| | - Yufeng Jia
- Operating Room, Traditional Chinese Medicine Hospital of Kunshan, Jiangsu Province, China
| | - Xiaoyan Xu
- Operating Room, Traditional Chinese Medicine Hospital of Kunshan, Jiangsu Province, China
| | - Weiye Shen
- Operating Room, Traditional Chinese Medicine Hospital of Kunshan, Jiangsu Province, China
| | - Ni Jin
- Operating Room, Traditional Chinese Medicine Hospital of Kunshan, Jiangsu Province, China
| | - Hongjie Du
- Department of Otolaryngology, Shandong Provincial Hospital Affiliated to Shandong First Medical University, China
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Song J, Wang M, Wang C, Zhang L. Olfactory dysfunction in chronic rhinosinusitis: insights into the underlying mechanisms and treatments. Expert Rev Clin Immunol 2023; 19:993-1004. [PMID: 37432663 DOI: 10.1080/1744666x.2023.2235891] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2023] [Accepted: 07/07/2023] [Indexed: 07/12/2023]
Abstract
INTRODUCTION Olfactory dysfunction (OD) is a typical symptom of chronic rhinosinusitis (CRS), which adversely affects the patient's quality of life and results in mood depression. Studies investigating the impairment of olfactory epithelium (OE) have indicated that inflammation-induced cell damage and dysfunction in OE plays a vital role in the development of OD. Consequently, glucocorticoids and biologics are beneficial in the management of OD in CRS patients. However, the mechanisms underlying OE impairment in CRS patients have not been fully elucidated. AREAS COVERED This review focuses on mechanisms underlying inflammation-induced cell impairment in OE of CRS patients. Additionally, the methods used for detection of olfaction and both currently available and potentially new clinical treatments for OD are reviewed. EXPERT OPINION Chronic inflammation in OE impairs not only olfactory sensory neurons but also non-neuronal cells that are responsible for regeneration and support for neurons. The current treatment for OD in CRS is mainly aimed at attenuating and preventing inflammation. Strategies for use of combinations of these therapies may achieve greater efficacy in restoration of the damaged OE and consequently better management of OD.
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Affiliation(s)
- Jing Song
- Department of Otolaryngology, Head and Neck Surgery, Beijing TongRen Hospital, Capital Medical University, Beijing, China
| | - Ming Wang
- Department of Otolaryngology, Head and Neck Surgery, Beijing TongRen Hospital, Capital Medical University, Beijing, China
- Beijing Key Laboratory of Nasal Diseases, Beijing Laboratory of Allergic Diseases, Beijing Institute of Otolaryngology, Beijing, China
| | - Chengshuo Wang
- Department of Otolaryngology, Head and Neck Surgery, Beijing TongRen Hospital, Capital Medical University, Beijing, China
- Beijing Key Laboratory of Nasal Diseases, Beijing Laboratory of Allergic Diseases, Beijing Institute of Otolaryngology, Beijing, China
| | - Luo Zhang
- Department of Otolaryngology, Head and Neck Surgery, Beijing TongRen Hospital, Capital Medical University, Beijing, China
- Beijing Key Laboratory of Nasal Diseases, Beijing Laboratory of Allergic Diseases, Beijing Institute of Otolaryngology, Beijing, China
- Department of Allergy, Beijing TongRen Hospital, Capital Medical University, Beijing, China
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5
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Fahmy M, Whitcroft K. Psychophysical Testing in Chemosensory Disorders. CURRENT OTORHINOLARYNGOLOGY REPORTS 2022; 10:393-404. [PMID: 36120187 PMCID: PMC9468236 DOI: 10.1007/s40136-022-00429-y] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 08/31/2022] [Indexed: 12/02/2022]
Abstract
Purpose of Review To provide an overview of psychophysical testing in olfaction and gustation. Recent Findings Subjective patient report correlates poorly with objective assessment of olfaction and gustation. It is therefore important that clinicians and researchers perform psychophysical testing during chemosensory assessment. There are several validated psychophysical tests of olfaction and gustation, with ongoing developments accelerated by the COVID-19 pandemic. These tests have been culturally and linguistically adapted globally. Screening tests have been developed with careful consideration to distinguish normosmics from those with olfactory dysfunction. Summary Validated chemosensory tools are available for use by the clinician to support screening, diagnosis, or monitoring. There are promising advances in self-assessment and screening that provide avenues for the development of a standardised pathway for identification and formal assessment of patients with smell and taste disorders.
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Affiliation(s)
- Miriam Fahmy
- ENT Department, Pinderfields Hospital, Mid Yorkshire Hospital NHS Trust, Wakefield, UK
- Wrexham, UK
| | - Katherine Whitcroft
- ENT Department, Pinderfields Hospital, Mid Yorkshire Hospital NHS Trust, Wakefield, UK
- UCL Ear Institute, London, UK
- Centre for Olfactory Research Applications, Institute of Philosophy, School of Advanced Study, London, UK
- Smell and Taste Clinic, Techniche Universität Dresden, Dresden, Germany
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6
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Asama Y, Furutani A, Fujioka M, Ozawa H, Takei S, Shibata S, Ogawa K. Analysis of conductive olfactory dysfunction using computational fluid dynamics. PLoS One 2022; 17:e0262579. [PMID: 35020767 PMCID: PMC8754295 DOI: 10.1371/journal.pone.0262579] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2021] [Accepted: 12/30/2021] [Indexed: 11/25/2022] Open
Abstract
Conductive olfactory dysfunction (COD) is caused by an obstruction in the nasal cavity and is characterized by changeable olfaction. COD can occur even when the olfactory cleft is anatomically normal, and therefore, the cause in these cases remains unclear. Herein, we used computational fluid dynamics to examine olfactory cleft airflow with a retrospective cohort study utilizing the cone beam computed tomography scan data of COD patients. By measuring nasal–nasopharynx pressure at maximum flow, we established a cut-off value at which nasal breathing can be differentiated from combined mouth breathing in COD patients. We found that increased nasal resistance led to mouth breathing and that the velocity and flow rate in the olfactory cleft at maximum flow were significantly reduced in COD patients with nasal breathing only compared to healthy olfactory subjects. In addition, we performed a detailed analysis of common morphological abnormalities associated with concha bullosa. Our study provides novel insights into the causes of COD, and therefore, it has important implications for surgical planning of COD, sleep apnea research, assessment of adenoid hyperplasia in children, and sports respiratory physiology.
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Affiliation(s)
- Youji Asama
- Asama Institute, Asama-ENT-Clinic, Koga, Ibaraki, Japan
- Department of Otolaryngology, Head and Neck Surgery School of Medicine, Keio University, Shinjuku, Tokyo, Japan
- Research Organization for Nano and Life Innovation, Waseda University, Shinjyuku-ku, Tokyo, Japan
| | - Akiko Furutani
- Asama Institute, Asama-ENT-Clinic, Koga, Ibaraki, Japan
- Research Organization for Nano and Life Innovation, Waseda University, Shinjyuku-ku, Tokyo, Japan
- * E-mail:
| | - Masato Fujioka
- Department of Otolaryngology, Head and Neck Surgery School of Medicine, Keio University, Shinjuku, Tokyo, Japan
| | - Hiroyuki Ozawa
- Department of Otolaryngology, Head and Neck Surgery School of Medicine, Keio University, Shinjuku, Tokyo, Japan
| | - Satoshi Takei
- Department of Otorhinolaryngology, Saitama City Hospital, Saitama, Japan
| | - Shigenobu Shibata
- Research Organization for Nano and Life Innovation, Waseda University, Shinjyuku-ku, Tokyo, Japan
| | - Kaoru Ogawa
- Department of Otolaryngology, Head and Neck Surgery School of Medicine, Keio University, Shinjuku, Tokyo, Japan
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Mason EC, Wu Z, McGhee S, Markley J, Koenigs M, Onwuka A, Chiang T, Zhao K. Computational Fluid Dynamic Modeling Reveals Nonlinear Airway Stress during Trachea Development. J Pediatr 2021; 238:324-328.e1. [PMID: 34284034 PMCID: PMC8551055 DOI: 10.1016/j.jpeds.2021.07.038] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/07/2021] [Revised: 06/21/2021] [Accepted: 07/14/2021] [Indexed: 11/28/2022]
Abstract
Normative trachea dimensions and aerodynamic information during development was collected to establish clinical benchmarks and showed that airway development seems to outpace respiratory demands. Infants and toddlers' trachea exhibit higher aerodynamic stress that significantly decreases by teenage years. This implies large airway pathology in younger children may have a more substantial clinical impact.
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Affiliation(s)
- Eric C Mason
- Department of Otolaryngology-Head and Neck Surgery, The Ohio State University, Columbus, OH
| | - Zhenxing Wu
- Department of Otolaryngology-Head and Neck Surgery, The Ohio State University, Columbus, OH
| | - Sam McGhee
- Department of Otolaryngology-Head and Neck Surgery, The Ohio State University, Columbus, OH
| | - Jennifer Markley
- Department of Otolaryngology-Head and Neck Surgery, The Ohio State University, Columbus, OH
| | - Maria Koenigs
- Department of Otolaryngology-Head and Neck Surgery, The Ohio State University, Columbus, OH
| | - Amanda Onwuka
- Center for Surgical Outcomes Research, The Research Institute at Nationwide Children's Hospital, Columbus, OH
| | - Tendy Chiang
- Department of Otolaryngology-Head and Neck Surgery, The Ohio State University, Columbus, OH; Department of Otolaryngology, Nationwide Children's Hospital, Columbus, OH; Center for Regenerative Medicine, The Research Institute at Nationwide Children's Hospital, Columbus, OH
| | - Kai Zhao
- Department of Otolaryngology-Head and Neck Surgery, The Ohio State University, Columbus, OH.
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8
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Computational modeling of nasal nitric oxide flux from the paranasal sinuses: Validation against human experiment. Comput Biol Med 2021; 136:104723. [PMID: 34388459 DOI: 10.1016/j.compbiomed.2021.104723] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2021] [Revised: 07/27/2021] [Accepted: 07/28/2021] [Indexed: 11/21/2022]
Abstract
BACKGROUND Nitric oxide (NO) is important in respiratory physiology and airway defense. Although the paranasal sinuses are the major source of nasal NO, transport dynamics between the sinuses and nasal cavities are poorly understood. METHODS Exhaled nasal NO tracings were measured in two non-asthmatic subjects (one with allergic rhinitis, one without) using NO analyzer connected via face mask. We subsequently performed computational fluid dynamics NO emission simulations based on individual CT scans and compared to the experimental data. RESULTS Simulated exhaled NO tracings match well with experimental data (r > 0.84, p < 0.01) for both subjects, with measured peaks reaching 319.6 ppb in one subject (allergic-rhinitis), and 196.9 ppb in the other. The CFD simulation accurately captured the peak differences, even though the initial sinus NO concentration for both cases was set to the same 9000 ppb based on literature value. Further, the CFD simulation suggests that ethmoid sinuses contributed the most (>67%, other sinuses combined <33%) to total nasal NO emission in both cases and that diffusion contributes more than convective transport. By turning off diffusion (setting NO diffusivity to ~0), the NO emission peaks for both cases were reduced by >70%. CONCLUSION Historically, nasal NO emissions were thought to be contributed mostly by the maxillary sinuses (the largest sinuses) and active air movement (convection). Here, we showed that the ethmoid sinuses and diffusive transport dominate the process. These findings may have a substantial impact on our view of nasal NO emission mechanisms and sinus physiopathology in general.
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Xavier R, Menger DJ, de Carvalho HC, Spratley J. An Overview of Computational Fluid Dynamics Preoperative Analysis of the Nasal Airway. Facial Plast Surg 2021; 37:306-316. [PMID: 33556971 DOI: 10.1055/s-0041-1722956] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022] Open
Abstract
Evaluation of the nasal airway is crucial for every patient with symptoms of nasal obstruction as well as for every patient with other nasal symptoms. This assessment of the nasal airway comprises clinical examination together with imaging studies, with the correlation between findings of this evaluation and symptoms reported by the patient being based on the experience of the surgeon. Measuring nasal airway resistance or nasal airflow can provide additional data regarding the nasal airway, but the benefit of these objective measurements is limited due to their lack of correlation with patient-reported evaluation of nasal breathing. Computational fluid dynamics (CFD) has emerged as a valuable tool to assess the nasal airway, as it provides objective measurements that correlate with patient-reported evaluation of nasal breathing. CFD is able to evaluate nasal airflow and measure variables such as heat transfer or nasal wall shear stress, which seem to reflect the activity of the nasal trigeminal sensitive endings that provide sensation of nasal breathing. Furthermore, CFD has the unique capacity of making airway analysis of virtual surgery, predicting airflow changes after trial virtual modifications of the nasal airway. Thereby, CFD can assist the surgeon in deciding surgery and selecting the surgical techniques that better address the features of each specific nose. CFD has thus become a trend in nasal airflow assessment, providing reliable results that have been validated for analyzing airflow in the human nasal cavity. All these features make CFD analysis a mainstay in the armamentarium of the nasal surgeon. CFD analysis may become the gold standard for preoperative assessment of the nasal airway.
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Affiliation(s)
- Rui Xavier
- Department of Otorhinolaryngology, Hospital Luz Arrabida, Porto, Portugal
| | - Dirk-Jan Menger
- Department of Otorhinolaringology, University Medical Center, Utrecht, The Netherlands
| | - Henrique Cyrne de Carvalho
- Department of Medicine, Instituto de Ciências Biomédicas Abel Salazar, Universidade do Porto, Porto, Portugal
| | - Jorge Spratley
- Department of Otorhinolaringology, Faculdade de Medicina da Universidade do Porto, Centro Hospitalar e Universitário S. João and Centro de Investigação em Tecnologias e Serviços de Saúde (CINTESIS), Porto, Portugal
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10
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Hazeri M, Faramarzi M, Sadrizadeh S, Ahmadi G, Abouali O. Regional deposition of the allergens and micro-aerosols in the healthy human nasal airways. JOURNAL OF AEROSOL SCIENCE 2021; 152:105700. [PMID: 33100375 PMCID: PMC7569476 DOI: 10.1016/j.jaerosci.2020.105700] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/23/2020] [Revised: 09/04/2020] [Accepted: 10/16/2020] [Indexed: 05/04/2023]
Abstract
The nasal cavity is the inlet to the human respiratory system and is responsible for the olfactory sensation, filtering pollutant particulate matter, and humidifying the air. Many research studies have been performed to numerically predict allergens, contaminants, and/or drug particle deposition in the human nasal cavity; however, the majority of these investigations studied only one or a small number of nasal passages. In the present study, a series of Computed Tomography (CT) scan images of the nasal cavities from ten healthy subjects were collected and used to reconstruct accurate 3D models. All models were divided into twelve anatomical regions in order to study the transport and deposition features of different regions of the nasal cavity with specific functions. The flow field and micro-particle transport equations were solved, and the total and regional particle deposition fractions were evaluated for the rest and low activity breathing conditions. The results show that there are large variations among different subjects. The standard deviation of the total deposition fraction in the nasal cavities was the highest for 5 × 10 4 <impaction parameter (IP)< 1.125 × 10 5 with a maximum of 20%. The achieved results highlighted the nasal cavity sections that are more involved in the particle deposition. Particles with IP = 30,000 deposit more in the middle turbinate and nasopharynx areas, while for particles with IP = 300,000, deposition is mainly in the anterior parts (kiesselbach and vestibule regions). For small IP values, the amounts of deposition fractions in different regions of the nasal cavity are more uniform.
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Affiliation(s)
- Mohammad Hazeri
- School of Mechanical Engineering, Shiraz University, Shiraz, Iran
| | - Mohammad Faramarzi
- Department of Otolaryngology-Head & Neck Surgery, Shiraz University of Medical Sciences, Shiraz, Iran
| | - Sasan Sadrizadeh
- Department of Civil and Architectural Engineering, KTH University, Stockholm, Sweden
| | - Goodarz Ahmadi
- Department of Mechanical & Aeronautical Engineering, Clarkson University, Potsdam, NY, USA
| | - Omid Abouali
- School of Mechanical Engineering, Shiraz University, Shiraz, Iran
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11
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Cooper KW, Brann DH, Farruggia MC, Bhutani S, Pellegrino R, Tsukahara T, Weinreb C, Joseph PV, Larson ED, Parma V, Albers MW, Barlow LA, Datta SR, Di Pizio A. COVID-19 and the Chemical Senses: Supporting Players Take Center Stage. Neuron 2020; 107:219-233. [PMID: 32640192 PMCID: PMC7328585 DOI: 10.1016/j.neuron.2020.06.032] [Citation(s) in RCA: 212] [Impact Index Per Article: 53.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2020] [Revised: 06/24/2020] [Accepted: 06/25/2020] [Indexed: 12/11/2022]
Abstract
The main neurological manifestation of COVID-19 is loss of smell or taste. The high incidence of smell loss without significant rhinorrhea or nasal congestion suggests that SARS-CoV-2 targets the chemical senses through mechanisms distinct from those used by endemic coronaviruses or other common cold-causing agents. Here we review recently developed hypotheses about how SARS-CoV-2 might alter the cells and circuits involved in chemosensory processing and thereby change perception. Given our limited understanding of SARS-CoV-2 pathogenesis, we propose future experiments to elucidate disease mechanisms and highlight the relevance of this ongoing work to understanding how the virus might alter brain function more broadly.
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Affiliation(s)
- Keiland W Cooper
- Interdepartmental Neuroscience Program, University of California Irvine, Irvine, CA, USA
| | - David H Brann
- Harvard Medical School Department of Neurobiology, Boston, MA, USA
| | | | - Surabhi Bhutani
- School of Exercise and Nutritional Sciences, San Diego State University, San Diego, CA, USA
| | - Robert Pellegrino
- Department of Food Science, Institute of Agriculture, University of Tennessee, Knoxville, TN, USA; Smell & Taste Clinic, Department of Otorhinolaryngology, TU Dresden, Dresden, Germany
| | | | - Caleb Weinreb
- Harvard Medical School Department of Neurobiology, Boston, MA, USA
| | - Paule V Joseph
- Division of Intramural Research, National Institute of Nursing Research (NINR) National Institutes of Health, Bethesda, MD, USA; National Institute on Alcohol Abuse and Alcoholism (NIAAA) National Institutes of Health, Bethesda, MD, USA
| | - Eric D Larson
- Department of Otolaryngology, University of Colorado, Anschutz Medical Campus, Aurora, CO, USA and the Rocky Mountain Taste and Smell Center, Aurora, CO, USA
| | - Valentina Parma
- Department of Psychology, Temple University, Philadelphia, PA, USA
| | - Mark W Albers
- Department of Neurology, Massachusetts General Hospital, Harvard Medical School, Charlestown, MA, USA
| | - Linda A Barlow
- Department of Cell and Developmental Biology, Graduate Program in Cell Biology, Stem Cells and Development and the Rocky Mountain Taste and Smell Center, University of Colorado, School Medicine, Anschutz Medical Campus, Aurora, CO, USA.
| | | | - Antonella Di Pizio
- Leibniz Institute for Food Systems Biology at the Technical University of Munich, Freising, Germany.
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12
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Hazeri M, Farshidfar Z, Faramarzi M, Sadrizadeh S, Abouali O. Details of the physiology of the aerodynamic and heat and moisture transfer in the normal nasal cavity. Respir Physiol Neurobiol 2020; 280:103480. [PMID: 32553890 DOI: 10.1016/j.resp.2020.103480] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/29/2020] [Revised: 06/11/2020] [Accepted: 06/11/2020] [Indexed: 12/13/2022]
Abstract
Anatomically accurate 3D models of 10 healthy nasal cavities are developed from computerized tomography (CT) scan images. Considering anatomical and physiological importance of different parts of the nasal cavity, the surface of each nasal passage is divided to eleven anatomical surfaces. Also the coronal cross sections in the nasal passage are divided to six sub-sections that share the total nasal passage airflow. The details of the flow field, heat transfer and water-vapor transport are numerically investigated for resting and low activity conditions. The mean and standard deviation of the different anatomical and air conditioning parameters such as: surface area, wall shear stress, heat and moisture transfer on different parts of the nasal passage surfaces and volume flow rates through different sections are presented. Results show that the percentages of airflow for inferior, middle and superior meatuses are 11.3 ± 6.4, 36.5 ± 9.5, 1.9 ± 0.81 % respectively and 4.1 ± 2.1 % of air passes through olfactory area. The inhaled air passing from the remaining surface (main passage) is 46.2 ± 10 %. Heat and moisture fluxes are highest in the anterior part of the nasal cavity, turbinates and lower part of the septum respectively. The percentage of the heat transfer from turbinates is 25.7 ± 3.9 % of total nasal heat transfer.
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Affiliation(s)
- Mohammad Hazeri
- School of Mechanical Engineering, Shiraz University, Shiraz, Iran
| | | | - Mohammad Faramarzi
- Department of Otolaryngology Head & Neck Surgery, Shiraz University of Medical Sciences, Shiraz, Iran
| | - Sasan Sadrizadeh
- Department of Civil and Architectural Engineering, KTH University, Stockholm, Sweden
| | - Omid Abouali
- School of Mechanical Engineering, Shiraz University, Shiraz, Iran.
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13
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Li C, Jiang J, Kim K, Otto BA, Farag AA, Cowart BJ, Pribitkin EA, Dalton P, Zhao K. Nasal Structural and Aerodynamic Features That May Benefit Normal Olfactory Sensitivity. Chem Senses 2019; 43:229-237. [PMID: 29474516 DOI: 10.1093/chemse/bjy013] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Nasal airflow that effectively transports ambient odors to the olfactory receptors is important for human olfaction. Yet, the impact of nasal anatomical variations on airflow pattern and olfactory function is not fully understood. In this study, 22 healthy volunteers were recruited and underwent computed tomographic scans for computational simulations of nasal airflow patterns. Unilateral odor detection thresholds (ODT) to l-carvone, phenylethyl alcohol (PEA) and d-limonene were also obtained for all participants. Significant normative variations in both nasal anatomy and aerodynamics were found. The most prominent was the formation of an anterior dorsal airflow vortex in some but not all subjects, with the vortex size being significantly correlated with ODT of l-carvone (r = 0.31, P < 0.05). The formation of the vortex is likely the result of anterior nasal morphology, with the vortex size varying significantly with the nasal index (ratio of the width and height of external nose, r = -0.59, P < 0.001) and nasal vestibule "notch" index (r = 0.76, P < 0.001). The "notch" is a narrowing of the upper nasal vestibule cartilage region. The degree of the notch also significantly correlates with ODT for PEA (r = 0.32, P < 0.05) and l-carvone (r = 0.33, P < 0.05). ODT of d-limonene, a low mucosal soluble odor, does not correlate with any of the anatomical or aerodynamic variables. The current study revealed that nasal anatomy and aerodynamics might have a significant impact on normal olfactory sensitivity, with greater airflow vortex and a narrower vestibule region likely intensifying the airflow vortex toward the olfactory region and resulting in greater olfactory sensitivity to high mucosal soluble odors.
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Affiliation(s)
- Chengyu Li
- Department of Otolaryngology-Head & Neck Surgery, The Ohio State University, Columbus, OH, USA
| | - Jianbo Jiang
- Department of Otolaryngology-Head & Neck Surgery, The Ohio State University, Columbus, OH, USA
| | - Kanghyun Kim
- Department of Otolaryngology-Head & Neck Surgery, The Ohio State University, Columbus, OH, USA.,Department of Biomedical Engineering, The Ohio State University, Columbus, OH, USA
| | - Bradley A Otto
- Department of Otolaryngology-Head & Neck Surgery, The Ohio State University, Columbus, OH, USA
| | - Alexander A Farag
- Department of Otolaryngology-Head & Neck Surgery, The Ohio State University, Columbus, OH, USA
| | - Beverly J Cowart
- Monell Chemical Senses Center, Philadelphia, PA, USA.,Department of Otolaryngology-Head & Neck Surgery, Thomas Jefferson University, Philadelphia, PA, USA
| | - Edmund A Pribitkin
- Department of Otolaryngology-Head & Neck Surgery, Thomas Jefferson University, Philadelphia, PA, USA
| | - Pamela Dalton
- Monell Chemical Senses Center, Philadelphia, PA, USA
| | - Kai Zhao
- Department of Otolaryngology-Head & Neck Surgery, The Ohio State University, Columbus, OH, USA.,Department of Biomedical Engineering, The Ohio State University, Columbus, OH, USA
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14
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Mason EC, McGhee S, Zhao K, Chiang T, Matrka L. The Application of Computational Fluid Dynamics in the Evaluation of Laryngotracheal Pathology. Ann Otol Rhinol Laryngol 2019; 128:453-459. [PMID: 30688077 DOI: 10.1177/0003489419826601] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
OBJECTIVES Laryngotracheal stenosis and obstruction can be challenging to manage. Traditional assessment tools are limited in clinical correlation. Three-dimensional computational fluid dynamics (CFD) modeling is a novel technique used to analyze airflow dynamics. The objective of this study was to apply CFD to the human upper airway to explore its utility. METHODS CFD models were constructed on an adult patient with an obstructive tracheal lesion before and after intervention and on an adult with normal airway anatomy, using computed tomographic imaging obtained retrospectively. Key airflow metrics were calculated. RESULTS CFD provided detailed airway geometry. The normal airway had a peak flow velocity of 3.12 m/s, wall shear stress of 0.30 Pa, and resistance of 0.02 Pa/mL/s. The pathologic patient showed an elevated peak flow velocity of 12.25 m/s, wall shear stress of 3.90 Pa, and resistance of 0.22 Pa/mL/s. This was reflected clinically with dyspnea, stridor, and obstructive impairment via pulmonary function testing. Following treatment, peak flow velocity corrected to 3.95 m/s, wall shear stress to 0.72Pa, and resistance to 0.01 Pa/mL/s. Cross-sectional area improved to 190 mm2 from a minimum of 53 mm2 at the same segment. Stridor and dyspnea resolved. CONCLUSIONS CFD metrics were calculated on the normal, diseased, and posttreatment upper airway. Variations were reflected in clinical symptoms. These methods could model surgical outcomes and anticipate disease severity.
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Affiliation(s)
- Eric C Mason
- 1 Department of Otolaryngology-Head & Neck Surgery, The Ohio State University Medical Center, Columbus, OH, USA
| | - Samuel McGhee
- 2 Department of Biomedical Engineering, College of Engineering, The Ohio State University, Columbus, OH, USA
| | - Kai Zhao
- 1 Department of Otolaryngology-Head & Neck Surgery, The Ohio State University Medical Center, Columbus, OH, USA.,2 Department of Biomedical Engineering, College of Engineering, The Ohio State University, Columbus, OH, USA
| | - Tendy Chiang
- 1 Department of Otolaryngology-Head & Neck Surgery, The Ohio State University Medical Center, Columbus, OH, USA.,3 Department of Otolaryngology-Head & Neck Surgery, Nationwide Children's Hospital, Columbus, OH, USA
| | - Laura Matrka
- 1 Department of Otolaryngology-Head & Neck Surgery, The Ohio State University Medical Center, Columbus, OH, USA
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15
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Abstract
Despite garnering minimal attention from the medical community overall, olfaction is indisputably critical in the manner in which we as humans interact with our surrounding environment. As the initial anatomical structure in the olfactory pathway, the nasal airway plays a crucial role in the transmission and perception of olfactory stimuli. The goal of this chapter is to provide a comprehensive overview of olfactory disturbances as it pertains to the sinonasal airway. This comprises an in-depth discussion of clinically relevant nasal olfactory anatomy and physiology, classification systems of olfactory disturbance, as well as the various etiologies and pathophysiologic mechanisms giving rise to this important disease entity. A systematic clinical approach to the diagnosis and clinical workup of olfactory disturbances is also provided in addition to an extensive review of the medical and surgical therapeutic modalities currently available.
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Affiliation(s)
- Joseph S. Schwartz
- Department of Otolaryngology—Head & Neck Surgery, McGill University, Montreal, QC, Canada
| | - Bobby A. Tajudeen
- Department of Otolaryngology—Head & Neck Surgery, Rush University, Chicago, IL, United States
| | - David W. Kennedy
- Department of Otorhinolaryngology—Head and Neck Surgery, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, United States,Correspondence to: David W. Kennedy, M.D., Department of Otorhinolaryngology—Head and Neck Surgery, Hospital of the University of Pennsylvania, 3400 Spruce St Ravdin 5, Philadelphia, PA 19104, United States. Tel: +1-215-662-6971, Fax: +1215-349-5977
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16
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Keustermans W, Huysmans T, Danckaers F, Zarowski A, Schmelzer B, Sijbers J, Dirckx JJJ. High quality statistical shape modelling of the human nasal cavity and applications. ROYAL SOCIETY OPEN SCIENCE 2018; 5:181558. [PMID: 30662757 PMCID: PMC6304114 DOI: 10.1098/rsos.181558] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/19/2018] [Accepted: 11/19/2018] [Indexed: 05/07/2023]
Abstract
The human nose is a complex organ that shows large morphological variations and has many important functions. However, the relation between shape and function is not yet fully understood. In this work, we present a high quality statistical shape model of the human nose based on clinical CT data of 46 patients. A technique based on cylindrical parametrization was used to create a correspondence between the nasal shapes of the population. Applying principal component analysis on these corresponded nasal cavities resulted in an average nasal geometry and geometrical variations, known as principal components, present in the population with a high precision. The analysis led to 46 principal components, which account for 95% of the total geometrical variation captured. These variations are first discussed qualitatively, and the effect on the average nasal shape of the first five principal components is visualized. Hereafter, by using this statistical shape model, two application examples that lead to quantitative data are shown: nasal shape in function of age and gender, and a morphometric analysis of different anatomical regions. Shape models, as the one presented here, can help to get a better understanding of nasal shape and variation, and their relationship with demographic data.
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Affiliation(s)
- William Keustermans
- Physics Department, University of Antwerp, Laboratory of Biophysics and Biomedical Physics, Groenenborgerlaan 171, 2020 Antwerp, Belgium
| | - Toon Huysmans
- Faculty of Industrial Design Engineering, TU Delft, Landbergstraat 15, 2628 CE Delft, The Netherlands
- Physics Department, University of Antwerp, Imec-Vision Lab, Edegemsesteenweg 200-240, 2610 Antwerp, Belgium
| | - Femke Danckaers
- Physics Department, University of Antwerp, Imec-Vision Lab, Edegemsesteenweg 200-240, 2610 Antwerp, Belgium
| | - Andrzej Zarowski
- ENT Department, GZA Sint-Augustinus Hospital, Oosterveldlaan 24, 2610 Antwerp, Belgium
| | - Bert Schmelzer
- ENT Department, ZNA Middelheim Hospital, Lindendreef 1, 2020 Antwerp, Belgium
| | - Jan Sijbers
- Physics Department, University of Antwerp, Imec-Vision Lab, Edegemsesteenweg 200-240, 2610 Antwerp, Belgium
| | - Joris J. J. Dirckx
- Physics Department, University of Antwerp, Laboratory of Biophysics and Biomedical Physics, Groenenborgerlaan 171, 2020 Antwerp, Belgium
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17
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Nishijima H, Kondo K, Yamamoto T, Nomura T, Kikuta S, Shimizu Y, Mizushima Y, Yamasoba T. Influence of the location of nasal polyps on olfactory airflow and olfaction. Int Forum Allergy Rhinol 2018; 8:695-706. [PMID: 29394000 DOI: 10.1002/alr.22089] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2017] [Revised: 12/12/2017] [Accepted: 01/04/2018] [Indexed: 11/07/2022]
Abstract
BACKGROUND Chronic rhinosinusitis with nasal polyps (CRSwNP) often results in decreased olfaction. In this study, we examined the relationship between nasal polyp location and olfactory airflow and odorant transport changes using virtual nasal polyp models at different locations and computational fluid dynamics (CFD) analysis. We also compared olfactory airflow and olfaction between patients with nasal polyps at different locations using CFD analysis and an olfactory test. METHODS Nasal computed tomography images were used to generate a normal model and 4 virtual nasal polyp models based on polyp locations, including the olfactory region (all-olfactory model), the region anterior to the olfactory region (preolfactory model), the middle meatus (middle-meatus model), and the superior meatus (superior-meatus model). Various airflow parameters were compared between these models and a normal model without polyps. We then performed a similar comparison between the 3-dimensional (3D) reconstruction models of patients with nasal polyps, and retrospectively investigated the correlation between olfaction and nasal polyp location in those patients. RESULTS Virtual nasal polyp analysis revealed dispersion of olfactory airflow in the all-olfactory model. Olfactory airflow and odorant transport showed maximum decrease in the preolfactory model and a slight decrease in the superior-meatus model. Olfactory airflow by polyps was further decreased by blockade of the olfactory airflow inlet than of the outlet. The findings obtained by patients corresponded well to those of the virtual polyp analysis. CONCLUSION Olfactory airflow and olfaction are differentially affected by nasal polyp location. This finding is important for planning polyp-removal surgeries from the perspective of improving patient olfaction.
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Affiliation(s)
| | - Kenji Kondo
- Department of Otolaryngology, The University of Tokyo, Tokyo, Japan
| | - Takahisa Yamamoto
- Department of Mechanical Engineering, National Institute of Technology, Gifu College, Gifu, Japan
| | - Tsutomu Nomura
- Department of Otolaryngology, Saitama Medical Center, Saitama Medical University, Saitama, Japan
| | - Shu Kikuta
- Department of Otolaryngology, The University of Tokyo, Tokyo, Japan
| | - Yuya Shimizu
- Department of Otolaryngology, The University of Tokyo, Tokyo, Japan
| | - Yu Mizushima
- Department of Otolaryngology, The University of Tokyo, Tokyo, Japan
| | - Tatsuya Yamasoba
- Department of Otolaryngology, The University of Tokyo, Tokyo, Japan
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18
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Victores AJ, Chen M, Smith A, Lane AP. Olfactory loss in chronic rhinosinusitis is associated with neuronal activation of c-Jun N-terminal kinase. Int Forum Allergy Rhinol 2017; 8:415-420. [PMID: 29193850 DOI: 10.1002/alr.22053] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2017] [Revised: 10/22/2017] [Accepted: 11/07/2017] [Indexed: 12/25/2022]
Abstract
BACKGROUND Olfactory inflammation in chronic rhinosinusitis (CRS) is associated with cytokines that may result in the death of olfactory sensory neurons. The principal signaling molecules involved in the apoptotic pathway are c-Jun N-terminal kinases (JNK). Although the JNK pathway has emerged as a key player in programmed cell death in neuroinflammation, its specific role in CRS-associated olfactory loss has not been thoroughly investigated. METHODS JNK activation was studied in human tissue samples from 9 control and 11 CRS patients by immunohistochemical staining for phosphorylated c-Jun. A mouse model of inducible olfactory cytokine expression was used to experimentally control inflammation and assess JNK activation over time. RESULTS In patients with CRS, activation of c-Jun is significantly increased relative to non-CRS control subjects, and there is an associated loss of sensory neurons. In the olfactory inflammation mouse model, prolonged induction of inflammation results in elevation of c-Jun expression and neuronal apoptosis. CONCLUSION Activation of neuronal JNK is a feature of chronic olfactory inflammation that is associated with neuronal apoptosis. Given that inhibition of JNK activity is neuroprotective in other settings, antagonism of this pathway may have therapeutic potential in the management of inflammatory olfactory loss or other disorders linked to olfactory neuronal apoptosis.
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Affiliation(s)
- Andrew J Victores
- Department of Otolaryngology-Head and Neck Surgery, Johns Hopkins University School of Medicine, Baltimore, MD
| | - Mengfei Chen
- Department of Otolaryngology-Head and Neck Surgery, Johns Hopkins University School of Medicine, Baltimore, MD
| | - Amy Smith
- Department of Otolaryngology-Head and Neck Surgery, Johns Hopkins University School of Medicine, Baltimore, MD
| | - Andrew P Lane
- Department of Otolaryngology-Head and Neck Surgery, Johns Hopkins University School of Medicine, Baltimore, MD
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19
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Li C, Jiang J, Dong H, Zhao K. Computational modeling and validation of human nasal airflow under various breathing conditions. J Biomech 2017; 64:59-68. [PMID: 28893392 DOI: 10.1016/j.jbiomech.2017.08.031] [Citation(s) in RCA: 76] [Impact Index Per Article: 10.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2017] [Revised: 08/25/2017] [Accepted: 08/27/2017] [Indexed: 10/18/2022]
Abstract
The human nose serves vital physiological functions, including warming, filtration, humidification, and olfaction. These functions are based on transport phenomena that depend on nasal airflow patterns and turbulence. Accurate prediction of these airflow properties requires careful selection of computational fluid dynamics models and rigorous validation. The validation studies in the past have been limited by poor representations of the complex nasal geometry, lack of detailed airflow comparisons, and restricted ranges of flow rate. The objective of this study is to validate various numerical methods based on an anatomically accurate nasal model against published experimentally measured data under breathing flow rates from 180 to 1100ml/s. The numerical results of velocity profiles and turbulence intensities were obtained using the laminar model, four widely used Reynolds-averaged Navier-Stokes (RANS) turbulence models (i.e., k-ε, standard k-ω, Shear Stress Transport k-ω, and Reynolds Stress Model), large eddy simulation (LES) model, and direct numerical simulation (DNS). It was found that, despite certain irregularity in the flow field, the laminar model achieved good agreement with experimental results under restful breathing condition (180ml/s) and performed better than the RANS models. As the breathing flow rate increased, the RANS models achieved more accurate predictions but still performed worse than LES and DNS. As expected, LES and DNS can provide accurate predictions of the nasal airflow under all flow conditions but have an approximately 100-fold higher computational cost. Among all the RANS models tested, the standard k-ω model agrees most closely with the experimental values in terms of velocity profile and turbulence intensity.
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Affiliation(s)
- Chengyu Li
- Department of Otolaryngology-Head and Neck Surgery, The Ohio State University, Columbus, OH, USA
| | - Jianbo Jiang
- Department of Otolaryngology-Head and Neck Surgery, The Ohio State University, Columbus, OH, USA
| | - Haibo Dong
- Department of Mechanical and Aerospace Engineering, University of Virginia, Charlottesville, VA, USA
| | - Kai Zhao
- Department of Otolaryngology-Head and Neck Surgery, The Ohio State University, Columbus, OH, USA.
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20
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Otto BA, Li C, Farag AA, Bush B, Krebs JP, Hutcheson RD, Kim K, Deshpande B, Zhao K. Computational fluid dynamics evaluation of posterior septectomy as a viable treatment option for large septal perforations. Int Forum Allergy Rhinol 2017; 7:718-725. [PMID: 28544511 DOI: 10.1002/alr.21951] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2017] [Revised: 04/06/2017] [Accepted: 04/14/2017] [Indexed: 11/06/2022]
Abstract
BACKGROUND Numerous surgical techniques exist to treat nasal septal perforation (NSP). The surgical closure of large NSPs (>2 cm) is still challenging. Posterior septectomy has been reported as a simple alternative to treat large NSP, yet its mechanisms for symptom relief are not clear, and if failed, its consequence cannot be easily reversed. METHODS Ten NSP patients were recruited: 5 underwent posterior septectomy and 5 underwent conventional flap or button repair. Computational fluid dynamics (CFD) simulated the nasal aerodynamics based on computed tomography (CT) scans. All patients had preoperative CT; however, only 4 had postoperative CT: 2 underwent posterior septectomy and the other 2 underwent flap repair. We examined surgical outcomes and the nasal airflow features among the 2 treatment options. RESULTS Both groups of patients had good outcomes based on chart review. Patients undergoing septectomy had significantly larger perforation size (2.32 ± 0.87 vs 1.21 ± 0.60 cm), higher flow rate across the perforation (47.8 ± 28.6 vs 18.3 ± 12.2 mL/second), and higher wall shear stress (WSS) along the posterior perforation margin (1.39 ± 0.52 vs 1.15 ± 0.58 Pa). The posterior WSS significantly correlated with crossover flow velocity (r = 0.77, p = 0.009) and was reduced by almost 67% postseptectomy, and by 29% postrepair. CONCLUSION This is the first CFD analysis on an NSP patient cohort. NSP resulted in flow disturbance and increased WSS that potentially led to symptomatology. The removal of high stress points along the posterior margin may explain why posterior septectomy can be an effective treatment option. Aerodynamic abnormalities, in addition to perforation size and location, could serve as basis for future treatment decisions.
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Affiliation(s)
- Bradley A Otto
- Department of Otolaryngology-Head & Neck Surgery, The Ohio State University, Columbus, OH
| | - Chengyu Li
- Department of Otolaryngology-Head & Neck Surgery, The Ohio State University, Columbus, OH
| | - Alexander A Farag
- Department of Otolaryngology-Head & Neck Surgery, The Ohio State University, Columbus, OH
| | - Benjamin Bush
- Department of Otolaryngology-Head & Neck Surgery, The Ohio State University, Columbus, OH
| | - Jillian P Krebs
- Department of Otolaryngology-Head & Neck Surgery, The Ohio State University, Columbus, OH
| | - Ryan D Hutcheson
- Department of Otolaryngology-Head & Neck Surgery, The Ohio State University, Columbus, OH
| | - Kanghyun Kim
- Department of Otolaryngology-Head & Neck Surgery, The Ohio State University, Columbus, OH
| | - Bhakthi Deshpande
- Department of Otolaryngology-Head & Neck Surgery, The Ohio State University, Columbus, OH
| | - Kai Zhao
- Department of Otolaryngology-Head & Neck Surgery, The Ohio State University, Columbus, OH
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21
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Lavin J, Min JY, Lidder AK, Huang JH, Kato A, Lam K, Meen E, Chmiel JS, Norton J, Suh L, Mahdavinia M, Hulse KE, Conley DB, Chandra RK, Shintani-Smith S, Kern RC, Schleimer RP, Tan BK. Superior turbinate eosinophilia correlates with olfactory deficit in chronic rhinosinusitis patients. Laryngoscope 2017; 127:2210-2218. [PMID: 28322448 DOI: 10.1002/lary.26555] [Citation(s) in RCA: 39] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2016] [Revised: 01/02/2017] [Accepted: 01/27/2017] [Indexed: 11/11/2022]
Abstract
OBJECTIVE To evaluate if molecular markers of eosinophilia in olfactory-enriched mucosa are associated with olfactory dysfunction. STUDY DESIGN Cross-sectional study of tissue biopsies from 99 patients, and an additional 30 patients who underwent prospective olfactory testing prior to sinonasal procedures. METHODS Tissue biopsies were processed for analysis of inflammatory markers using quantitative real time polymerase chain reaction (qRT-PCR). Ipsilateral olfactory performance was assessed using the Sniffin' Sticks (Burghart, Wedel, Germany) threshold component and the University of Pennsylvania Smell Identification Test (Sensonics, Haddon Heights, NJ). Age-adjusted data was correlated with inflammatory marker expression and clinical measures of obstruction from computed tomography and endoscopy. RESULTS Gene expression of the eosinophil marker CLC (Charcot Leyden crystal protein) was elevated in superior turbinate (ST) tissue in chronic rhinosinusitis (CRS) with nasal polyps (CRSwNP) compared to ST and inferior turbinate tissue in CRS without nasal polyps (CRSsNP) and control patients (all P < 0.001, respectively). CLC in ST tissue was correlated with IL-5 and eotaxin-1 expression (all P < 0.001; P = 0.65, and 0.49, respectively). CLC expression was strongly correlated with eosinophilic cationic protein levels (P < 0.001; r = -0.76), and ST CLC expression was inversely related to olfactory threshold (P = 0.002, r = -0.57) and discrimination scores (P = 0.05, r = -0.42). In multiple linear regression of CLC gene expression, polyp status, and radiographic and endoscopic findings with olfactory threshold, CLC was the only significantly correlated variable (P < 0.05). CONCLUSION Markers of eosinophils are elevated in the ST of patients with CRSwNP and correlate with olfactory loss. These findings support the hypothesis that olfactory dysfunction in CRS correlates local eosinophil influx into the olfactory cleft. LEVEL OF EVIDENCE NA. Laryngoscope, 127:2210-2218, 2017.
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Affiliation(s)
- Jennifer Lavin
- Department of Otolaryngology-Head and Neck SurgeryDivision of Pediatric Otolaryngology, Ann & Robert H. Lurie Children's Hospital of Chicago, Northwestern University Feinberg School of Medicine, Chicago, Illinois, U.S.A
| | - Jin-Young Min
- Department of Otolaryngology-Head and Neck SurgeryDivision of Pediatric Otolaryngology, Ann & Robert H. Lurie Children's Hospital of Chicago, Northwestern University Feinberg School of Medicine, Chicago, Illinois, U.S.A
| | - Alcina K Lidder
- University of Rochester School of Medicine and Dentistry, Rochester, New York, U.S.A
| | - Julia He Huang
- Department of Otolaryngology-Head and Neck SurgeryDivision of Pediatric Otolaryngology, Ann & Robert H. Lurie Children's Hospital of Chicago, Northwestern University Feinberg School of Medicine, Chicago, Illinois, U.S.A
| | - Atsushi Kato
- Division of Allergy and Immunology, Northwestern University Feinberg School of Medicine, Chicago, Illinois, U.S.A
| | - Kent Lam
- Department of Otolaryngology-Head and Neck Surgery, Eastern Virginia Medical School, Norfolk, Virginia, U.S.A
| | - Eric Meen
- Department of Otolaryngology-Head and Neck Surgery, University of Manitoba, Winnipeg, Canada
| | - Joan S Chmiel
- Department of Preventive Medicine-Biostatistics, Northwestern University Feinberg School of Medicine, Chicago, Illinois, U.S.A
| | - James Norton
- Division of Allergy and Immunology, Northwestern University Feinberg School of Medicine, Chicago, Illinois, U.S.A
| | - Lydia Suh
- Division of Allergy and Immunology, Northwestern University Feinberg School of Medicine, Chicago, Illinois, U.S.A
| | - Mahboobeh Mahdavinia
- Division of Allergy and Immunology, Rush Medical College, Chicago, Illinois, U.S.A
| | - Kathryn E Hulse
- Division of Allergy and Immunology, Northwestern University Feinberg School of Medicine, Chicago, Illinois, U.S.A
| | - David B Conley
- Department of Otolaryngology-Head and Neck SurgeryDivision of Pediatric Otolaryngology, Ann & Robert H. Lurie Children's Hospital of Chicago, Northwestern University Feinberg School of Medicine, Chicago, Illinois, U.S.A
| | - Rakesh K Chandra
- Department of Otolaryngology, Head and Neck Surgery, Vanderbilt School of Medicine, Nashville, Tennessee, U.S.A
| | - Stephanie Shintani-Smith
- Department of Otolaryngology-Head and Neck SurgeryDivision of Pediatric Otolaryngology, Ann & Robert H. Lurie Children's Hospital of Chicago, Northwestern University Feinberg School of Medicine, Chicago, Illinois, U.S.A
| | - Robert C Kern
- Department of Otolaryngology-Head and Neck SurgeryDivision of Pediatric Otolaryngology, Ann & Robert H. Lurie Children's Hospital of Chicago, Northwestern University Feinberg School of Medicine, Chicago, Illinois, U.S.A
| | - Robert P Schleimer
- Department of Otolaryngology-Head and Neck SurgeryDivision of Pediatric Otolaryngology, Ann & Robert H. Lurie Children's Hospital of Chicago, Northwestern University Feinberg School of Medicine, Chicago, Illinois, U.S.A.,University of Rochester School of Medicine and Dentistry, Rochester, New York, U.S.A
| | - Bruce K Tan
- Department of Otolaryngology-Head and Neck SurgeryDivision of Pediatric Otolaryngology, Ann & Robert H. Lurie Children's Hospital of Chicago, Northwestern University Feinberg School of Medicine, Chicago, Illinois, U.S.A
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Nishijima H, Kondo K, Nomura T, Yamasoba T. Ethmoidectomy combined with superior meatus enlargement increases olfactory airflow. Laryngoscope Investig Otolaryngol 2017; 2:136-146. [PMID: 28894833 PMCID: PMC5562944 DOI: 10.1002/lio2.59] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2016] [Revised: 11/05/2016] [Accepted: 11/10/2016] [Indexed: 11/11/2022] Open
Abstract
OBJECTIVES The relationship between a particular surgical technique in endoscopic sinus surgery (ESS) and airflow changes in the post-operative olfactory region has not been assessed. The present study aimed to compare olfactory airflow after ESS between conventional ethmoidectomy and ethmoidectomy with superior meatus enlargement, using virtual ESS and computational fluid dynamics (CFD) analysis. STUDY DESIGN Prospective computational study. MATERIALS AND METHODS Nasal computed tomography images of four adult subjects were used to generate models of the nasal airway. The original preoperative model was digitally edited as virtual ESS by performing uncinectomy, ethmoidectomy, antrostomy, and frontal sinusotomy. The following two post-operative models were prepared: conventional ethmoidectomy with normal superior meatus (ESS model) and ethmoidectomy with superior meatus enlargement (ESS-SM model). The calculated three-dimensional nasal geometries were confirmed using virtual endoscopy to ensure that they corresponded to the post-operative anatomy observed in the clinical setting. Steady-state, laminar, inspiratory airflow was simulated, and the velocity, streamline, and mass flow rate in the olfactory region were compared among the preoperative and two postoperative models. RESULTS The mean velocity in the olfactory region, number of streamlines bound to the olfactory region, and mass flow rate were higher in the ESS-SM model than in the other models. CONCLUSION We successfully used an innovative approach involving virtual ESS, virtual endoscopy, and CFD to assess postoperative outcomes after ESS. It is hypothesized that the increased airflow to the olfactory fossa achieved with ESS-SM may lead to improved olfactory function; however, further studies are required. LEVEL OF EVIDENCE NA.
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Affiliation(s)
| | - Kenji Kondo
- Department of Otolaryngology The University of Tokyo Tokyo Japan
| | - Tsutomu Nomura
- Department of Otolaryngology Saitama Medical Center, Saitama Medical University Saitama Japan
| | - Tatsuya Yamasoba
- Department of Otolaryngology The University of Tokyo Tokyo Japan
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Olfactory dysfunction in Multiple Sclerosis: A scoping review of the literature. Mult Scler Relat Disord 2015; 6:1-9. [PMID: 27063616 DOI: 10.1016/j.msard.2015.12.002] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2015] [Revised: 11/30/2015] [Accepted: 12/01/2015] [Indexed: 11/23/2022]
Abstract
OBJECTIVE Olfactory dysfunction in Multiple Sclerosis (MS) has been reported, but results have been inconsistent. In this review we describe, synthesize, and interpret the existing literature on olfactory dysfunction in Multiple Sclerosis and identify gaps in the current level of knowledge. METHODS The study design was a scoping review of the literature covering several study designs. Systematic Searches of the PubMed, CINAHL, Cochrane Library, Web of Science, PsycARTICLES, PsycINFO and Google Scholar databases were conducted that included key words related to Multiple Sclerosis and Olfaction Disorders. Literature that met the criteria of pertaining to both Multiple Sclerosis and olfactory dysfunction was identified, with the aim of providing an overview of the extent and types of research available in this area. RESULTS Sixty-one reports were identified in the initial search, with 40 meeting the study criteria. Twenty-five clinical studies were included. Among them, 23 studies measured for olfactory dysfunction in MS patients, ten evaluated MRI correlates of olfactory dysfunction, and five evaluated neurophysiology correlates of olfactory dysfunction. Six of the included studies were abstracts. In addition, thirteen reviews/commentaries and two case studies were included. The majority of the studies identified some degree of olfactory dysfunction in MS patients, and various aspects and correlations with olfactory impairment were observed. CONCLUSIONS The overall weight of the literature suggests that olfactory dysfunction may occur in MS. Although there is variability in reported frequency, the more robust studies suggest the prevalence is significant, ranging from 20% to 45% in the MS population. Despite this, the mechanisms are unknown and the clinical relevance of this association has not been well explored. Interesting findings relating mood disorders, cognition, and olfactory dysfunction in MS are also suggested but remain poorly developed and require further investigation. Future studies are also warranted to understand the dynamic changes in olfactory function during the course of MS, and to correlate olfactory function with relapses/disease activity.
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Zhao K, Malhotra P, Rosen D, Dalton P, Pribitkin EA. Computational fluid dynamics as surgical planning tool: a pilot study on middle turbinate resection. Anat Rec (Hoboken) 2015; 297:2187-95. [PMID: 25312372 DOI: 10.1002/ar.23033] [Citation(s) in RCA: 40] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2014] [Accepted: 06/25/2014] [Indexed: 11/08/2022]
Abstract
Controversies exist regarding the resection or preservation of the middle turbinate (MT) during functional endoscopic sinus surgery. Any MT resection will perturb nasal airflow and may affect the mucociliary dynamics of the osteomeatal complex. Neither rhinometry nor computed tomography (CT) can adequately quantify nasal airflow pattern changes following surgery. This study explores the feasibility of assessing changes in nasal airflow dynamics following partial MT resection using computational fluid dynamics (CFD) techniques. We retrospectively converted the pre- and postoperative CT scans of a patient who underwent isolated partial MT concha bullosa resection into anatomically accurate three-dimensional numerical nasal models. Pre- and postsurgery nasal airflow simulations showed that the partial MT resection resulted in a shift of regional airflow towards the area of MT removal with a resultant decreased airflow velocity, decreased wall shear stress and increased local air pressure. However, the resection did not strongly affect the overall nasal airflow patterns, flow distributions in other areas of the nose, nor the odorant uptake rate to the olfactory cleft mucosa. Moreover, CFD predicted the patient's failure to perceive an improvement in his unilateral nasal obstruction following surgery. Accordingly, CFD techniques can be used to predict changes in nasal airflow dynamics following partial MT resection. However, the functional implications of this analysis await further clinical studies. Nevertheless, such techniques may potentially provide a quantitative evaluation of surgical effectiveness and may prove useful in preoperatively modeling the effects of surgical interventions.
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Affiliation(s)
- Kai Zhao
- Monell Chemical Senses Center, Philadelphia, Pennsylvania; Department of Otolaryngology, Thomas Jefferson University, Philadelphia, Pennsylvania
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