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Head and neck
Published in David A Lisle, Imaging for Students, 2012
Acute sinusitis is usually viral or bacterial and presents clinically with facial pain and headache, nasal discharge and fever. Diagnosis is usually made on clinical grounds and may be confirmed with nasal cultures or minimally invasive procedures such as endoscopic paranasal sinus aspiration. Imaging usually is not required for acute sinusitis. Indications for imaging in suspected acute paranasal sinusitis include:Lack of response to antibiotic therapyImmunocompromised patientsSuspected complications, such as meningitis, subdural empyema or cerebral abscess.
General Thermography
Published in James Stewart Campbell, M. Nathaniel Mead, Human Medical Thermography, 2023
James Stewart Campbell, M. Nathaniel Mead
Along with viral infections and allergies, chronic sinusitis can be caused by structural abnormalities in the nasal passages, a tumor, or nasal polyp that keeps the sinuses from draining normally.75 Chronic fungal infection of the sinuses can also occur. Thermography is useful to differentiate bacterial sinusitis versus viral or congestive sinus pain. The thermographic appearance of chronic fungal sinusitis and other conditions remains to be studied.
Multi-Cyclodextrin Supramolecular Encapsulation Entities for Multifaceted Topical Drug Delivery Applications
Published in Munmaya K. Mishra, Applications of Encapsulation and Controlled Release, 2019
P. D. Kondiah, Yahya E. Choonara, Zikhona Hayiyana, Pariksha J. Kondiah, Thashree Marimuthu, Lisa C. du Toit, Pradeep Kumar, Viness Pillay
The mucous membranes cover internal organs (buccal, nasal, and sublingual mucosae) and form linings in cavities exposed to external organs. The nasal mucosa–targeting drugs are commonly formulated as nasal sprays, allowing maximum absorption for immediate therapeutic benefits. Thus, these routes of administration are essential for bypassing hepatic metabolism, allowing significant concentrations of encapsulated drug to be absorbed due to the profusely rich blood supply.
Validating CFD predictions of nasal spray deposition: Inclusion of cloud motion effects for two spray pump designs
Published in Aerosol Science and Technology, 2022
Arun V. Kolanjiyil, Sana Hosseini, Ali Alfaifi, Dale Farkas, Ross Walenga, Andrew Babiskin, Michael Hindle, Laleh Golshahi, P. Worth Longest
Delivering pharmaceutical formulations in aerosol form directly to the nose is an attractive approach to combat diseases and disorders such as allergic rhinitis, sinusitis, nasal polyposis and migraines (Djupesland 2013; Dykewicz and Hamilos 2010; Le Guellec, Ehrmann, and Vecellio 2021). Nasal spray pumps are commonly used as drug delivery systems to administer locally acting pharmaceutical formulations to the nasal mucosa (Macias-Valle and Psaltis 2020). In addition to the already approved and marketed nasal spray innovator and generic products, many new and generic products are under development (Choi et al. 2018; Li et al. 2013). Furthermore, investigations are underway to deliver medications and vaccines to the nasal airways to combat SARS-CoV-2 and other respiratory viruses (Csaba, Garcia-Fuentes, and Alonso 2009; Wilkins et al. 2021; Zhang et al. 2020). Hence, it is important to develop and improve strategies for testing nasal spray device drug delivery performance under variable usage conditions (Newman, Pitcairn, and Dalby 2004).
Micro- and nanoparticle transport and deposition in a realistic neonatal and infant nasal upper airway
Published in International Journal of Modelling and Simulation, 2023
John Valerian Corda, B Satish Shenoy, Kamarul Arifin Ahmad, Leslie Lewis, Prakashini K, Anoop Rao, Mohammad Zuber
The human nasal cavity acts as the first line of filtration of the inhaled dust and unwanted particles so that the inspired air enters the lungs in the purest form possible. In addition to the filtration, the nasal cavity also performs the thermal conditioning and humidification of the inspired air [30]. Nasal geometry is a complicated flow domain and in vivo measurements for flow and particle depositions are challenging due to which researchers have sought to use in silico methods using CFD to effectively determine the required flow parameters [31–35].
Voxel-based simulation of flow and temperature in the human nasal cavity
Published in Computer Methods in Biomechanics and Biomedical Engineering, 2020
Shinya Kimura, Shuta Miura, Toshihiro Sera, Hideo Yokota, Kenji Ono, Denis J. Doorly, Robert C. Schroter, Gaku Tanaka
The nasal airway plays various roles as part of the upper respiratory system, which extends from the nasal cavity to the trachea. Sensing odorant molecules and filtering pollutants and airborne particles across the nasal mucosa are the primary functions. The nasal cavity has an air-conditioning function to ensure the inspiratory air is at the proper temperature and humidity to protect the lower respiratory tract (Elad et al. 2008). Inspired air is heated and humidified by the mucosa layer with rich blood vessels as it travels from the nostrils to the nasopharynx (Keck et al. 2000; Lindemann et al. 2002). In addition, it was suggested that subjective perception of nasal obstruction may correlate better with mucosal cooling, rather than with nasal resistance (Sullivan et al. 2014). Therefore, it is important to clarify the heat transfer characteristics in the nasal cavity. Because the intricate anatomy of the nasal cavity makes it difficult to predict detailed airflow patterns in-vivo (Lang 1989), physical models of the nasal cavity derived from medical images have been used in both experimental (Hahn et al. 1993; Kelly et al. 2000; Chung et al. 2006; Chung and Kim 2008; Doorly et al. 2008) and computational (Keyhani et al. 1995; Zhao et al. 2006; Doorly et al. 2008; Taylor et al. 2010) studies to determine the detailed patterns of the nasal airflow. In particular, computational fluid dynamics (CFD) has enabled detailed airflow simulation throughout the nasal cavity based on CT scans of individual subjects (Croce et al. 2006; Ishikawa et al. 2006; Doorly et al. 2008; Gambaruto et al. 2009; Kumahata et al. 2010; Taylor et al. 2010; Na et al. 2012; Bates et al. 2015). To model a realistic nasal cavity shape with a computational grid in CFD, boundary-fitted grids are currently used. On one hand, this method is capable of accurately reconstructing the complex geometry using thin boundary layers allocated along the surface. On the other hand, this method requires high-quality grid generation, which affects calculation accuracy.