Air-conditioning characteristics in nasal cavity models exhibiting nasal cycle states

Acoustic rhinometry (AR) evaluates the geometry of the nasal cavity with acoustic reflections and provides information about nasal cross-sectional areas (CSA) and nasal volume within a given distance. The accuracy of the information obtained by AR was compared with that of magnetic resonance imaging (MRI) of the nasal cavity. Five healthy subjects were evaluated with AR and the MRI before and after the application of a long-acting nasal decongestant spray, to eliminate possible interference of the nasal cycle with both measurement techniques. The MRI images of 2 mm coronal sections of the nasal cavity were traced by three independent observers and the CSAs were calculated by computer-aided imaging digitization, to be compared with the calculated CSAs obtained with the AR at the corresponding distance from the nasal tip. Digitized data from the MRI images were also used to calculate the nasal volume within the first 6 cm from the nasal tip and compared with the AR volume measurements. The interobserver variation of digitized MRI data predecongestant and postdecongestant was not significant. The correlations of CSA and volume measurements between the AR and MRI were high (0.969) after the application of the decongestant. The correlation between the AR and MRI measurements before the decongestant was low (0.345). This may have been the result of interference of the nasal cycle during the long MRI measurements (1 hour) or other unknown factors. We conclude that AR measurements of nasal CSAs and volumes provide accurate information when compared with the MRI of the decongested nasal airway.

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Air-conditioning in the human nasal cavity

Respiratory Physiology & Neurobiology ◽

10.1016/j.resp.2008.05.002 ◽

2008 ◽

Vol 163 (1-3) ◽

pp. 121-127 ◽

Cited By ~ 92

Author(s):

David Elad ◽

Michael Wolf ◽

Tilman Keck

Keyword(s):

Nasal Cavity ◽

Air Conditioning

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Air-conditioning characteristics of the human nose

The Journal of Laryngology & Otology ◽

10.1258/002221504772784504 ◽

2004 ◽

Vol 118 (2) ◽

pp. 87-92 ◽

Cited By ~ 52

Author(s):

Michael Wolf ◽

Sara Naftali ◽

Robert C. Schroter ◽

David Elad

Keyword(s):

Body Temperature ◽

Literature Review ◽

Nasal Cavity ◽

Air Conditioning ◽

Current Knowledge ◽

Ambient Air ◽

Computational Studies ◽

Human Nose

Nasal inspiration is important for maintaining the internal milieu of the lung, since ambient air is conditioned to nearly alveolar conditions (body temperature and fullysaturated with water vapour) upon reaching the nasopharynx. This literature review of the existing in vivo, in vitro and computational studies on transport phenomena that take place within the human nasal cavity summarizes the current knowledge on air-conditioning characteristics of the human nose.

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A Model of Airflow in the Nasal Cavities: Implications for Nasal Air Conditioning and Epistaxis

American Journal of Rhinology and Allergy ◽

10.2500/ajra.2009.23.3308 ◽

2009 ◽

Vol 23 (3) ◽

pp. 244-249 ◽

Cited By ~ 13

Author(s):

Neil Bailie ◽

Brendan Hanna ◽

John Watterson ◽

Geraldine Gallagher

Keyword(s):

Shear Stress ◽

Wall Shear Stress ◽

Nasal Cavity ◽

Air Conditioning ◽

Computational Models ◽

Middle Turbinate ◽

Inferior Turbinate ◽

Nasal Airflow ◽

Wall Shear ◽

Little’S Area

Background A friction force is generated when moving air contacts the nasal walls, referred to as wall shear stress. This interaction facilitates heat and mass transfer between the mucosa and air, i.e., air-conditioning. The objective of this research was to study the distribution of wall shear stress within the nasal cavity to identify areas that contribute significantly to air-conditioning within the nasal cavity. Methods Three-dimensional computational models of the nasal airways of five healthy subjects (three male and two female subjects) were constructed from nasal CT scans. Numerical simulations of nasal airflow were conducted using the commercial computational fluid dynamics code Fluent 6 (Ansys, Inc., Canonsburg, PA). Wall shear stress was derived from the numerical simulation. Air-conditioning was simulated to confirm the relationship with wall shear stress. Results Nasal airflow simulations predicted high wall shear stress along the anterior aspect of the inferior turbinate, the anteroinferior aspect of the middle turbinate, and within Little's area. Conclusion The airflow simulations indicate that the inferior and middle turbinates and Little's area on the anterior nasal septum contribute significantly to nasal air-conditioning. The concentration of wall shear stress within Little's area indicates a desiccating and potentially traumatic effect of inhaled air that may explain the predilection for spontaneous epistaxis at this site.

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What Does Nasal Cavity Size Tell us about Functional Nasal Airways?

Bulletins et Mémoires de la Société d anthropologie de Paris ◽

10.3166/bmsap-2018-0011 ◽

2018 ◽

Vol 31 (1-2) ◽

pp. 69-76 ◽

Cited By ~ 3

Author(s):

Y. Heuzé

Keyword(s):

Nasal Cavity ◽

Air Conditioning ◽

Soft Tissues ◽

Volume Ratio ◽

University Hospital ◽

Facial Morphology ◽

Nasal Airways ◽

Computed Tomography Images ◽

Low Correlation ◽

Human Skulls

Studies on dry human skulls have shown that nasal cavity (NC) morphology varies with eco-geographic factors. These findings have been used by some authors to interpret the facial morphology of Neanderthals. However, respiratory and air-conditioning functions are primarily carried out by the nasal airways (NA), which are delimited by mucosa. The aims of this study were to test whether: (1) NC volume (V) and surface-area-to-volume ratio (SA/ V) are proportional to NA counterparts; (2) measurements for male NC and NA are larger than in females; (3) the centroid size (CS) of a set of landmarks measured on NC provides a reliable proxy for NC V. Head CT (computed tomography) images of adult patients (N = 30) at the University Hospital of Bordeaux were selected retrospectively. NA were defined by segmenting the lumen corresponding to the functional volume. NC was defined by adding to NA the soft tissues delimited by the bones forming the NC. The coordinates of 16 landmarks measured on NC bones were recorded. A rather low correlation was found between NA and NC V while NA SA/V and NC SA/V were not correlated. No significant differences were found between male and female NA and NC measurements. A rather low correlation was found between NC Vand NC CS. If these preliminary results were to be confirmed by future studies, results using NC as a proxy for NA focusing on air-conditioning and respiratory energetics might need to be re-interpreted.

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Numerical study on the air conditioning characteristics of the human nasal cavity

Computers in Biology and Medicine ◽

10.1016/j.compbiomed.2017.04.018 ◽

2017 ◽

Vol 86 ◽

pp. 18-30 ◽

Cited By ~ 9

Author(s):

Da-Woon Kim ◽

Seung-Kyu Chung ◽

Yang Na

Keyword(s):

Nasal Cavity ◽

Air Conditioning ◽

Numerical Study

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Impaired Air Conditioning within the Nasal Cavity in Flat-Faced Homo

PLoS Computational Biology ◽

10.1371/journal.pcbi.1004807 ◽

2016 ◽

Vol 12 (3) ◽

pp. e1004807 ◽

Cited By ~ 10

Author(s):

Takeshi Nishimura ◽

Futoshi Mori ◽

Sho Hanida ◽

Kiyoshi Kumahata ◽

Shigeru Ishikawa ◽

...

Keyword(s):

Nasal Cavity ◽

Air Conditioning

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Concha bullosa and the nasal middle meatus obstructive syndrome

Vojnosanitetski pregled ◽

10.2298/vsp0803255p ◽

2008 ◽

Vol 65 (3) ◽

pp. 255-258 ◽

Cited By ~ 5

Author(s):

Aleksandar Peric ◽

Jelena Sotirovic ◽

Nenad Baletic ◽

Ruzica Kozomara ◽

Dusan Bijelic ◽

...

Keyword(s):

Nasal Cavity ◽

Anatomic Variation ◽

Middle Turbinate ◽

Common Symptom ◽

Middle Meatus ◽

Concha Bullosa ◽

Nasal Breathing ◽

Nasal Cycle ◽

Important Symptom ◽

The Right

Background. Concha bullosa (CB) is pneumatization of the middle turbinate and one of the most common anatomic variation of the sinonasal region. It is found in about 25% of the population. Middle meatus obstructive syndrome (MMOS) is, usually connected with CB. The main symptoms of this syndrome are headaches, impaired nasal breathing and hyposmia. Headache is the most common symptom and it may occur due to contact between a CB and other structures of the nasal cavity. Case report. We presented a case of 32 year-old-woman with headaches, located in the orbital and the left frontal region. The headaches were intermittent and corresponding to the nasal cycle. After neurologic and alergic examination, endoscopic nasal examination demonstrated a septal deviation to the right side and a large middle turbinate in the left side of the nasal cavity. Coronal computerized tomography (CT) of the paranasal sinuses demonstrated the septal deformation and pneumatization of the left middle turbinate. Diagnosis was confirmed by lidocaine test. In the functional endoscopic surgery (FESS), the lateral lamela of the anterior CB was removed. At the same time, the septoplasty was done. At the control examination, the patient was without symptoms. Conclusion. Although CB is the common anatomic variation of the nasal cavity, MMOS is rare. Headache (rhinogenic origin) is the most important symptom. Surgical treatment is the lateral resection of the CB in the FESS technique and the septoplasty.

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Influence of the Turbinate Volumes as Measured by Magnetic Resonance Imaging on Nasal Air Conditioning

American Journal of Rhinology and Allergy ◽

10.2500/ajra.2009.23.3309 ◽

2009 ◽

Vol 23 (3) ◽

pp. 250-254 ◽

Cited By ~ 5

Author(s):

Joerg Lindemann ◽

Evangelia Tsakiropoulou ◽

Victor Vital ◽

Tilman Keck ◽

Richard Leiacker ◽

...

Keyword(s):

Magnetic Resonance Imaging ◽

Magnetic Resonance ◽

Nasal Cavity ◽

Air Temperature ◽

Air Conditioning ◽

Middle Turbinate ◽

Acoustic Rhinometry ◽

Resonance Imaging ◽

Cross Sectional ◽

Temperature And Humidity

Background Changes in nasal airflow caused by varying intranasal volumes and cross-sectional areas affect the contact between air and surrounding mucosa entailing alterations in nasal air conditioning. This study evaluates the correlation between nasal air conditioning and the volumes of the inferior and middle turbinates as measured by magnetic resonance imaging (MRI). Methods Fourteen healthy volunteers were enrolled. Each volunteer had been examined by rhinomanometry, acoustic rhinometry, intranasal air temperature, and humidity measurements at defined intranasal sites as well as MRI of the nasal cavity and the paranasal sinuses. The volumetric data of the turbinates was based on the volumetric software Amira. Results Comparable results were obtained regarding absolute humidity values and temperature values within the nasal valve area and middle turbinate area for both the right and the left side of the nasal cavity. No statistically significant differences were found in the rhinomanometric values and the acoustic rhinometry results of both sides (p > 0.05). No statistical correlations were found between the volumes of the inferior (mean, 6.1 cm3) and middle turbinate (mean, 1.8 cm3) and the corresponding humidity and temperature values. Additionally, the air temperature and humidity values did not correlate with the rhinometrical endonasal volumes (0–20 mm and 20–50 mm from the nasal entrance). Conclusion The normal range of volumes of the inferior and middle turbinate does not seem to have a significant impact on intranasal air conditioning in healthy subjects. The exact limits where alterations of the turbinate volume negatively affect nasal air conditioning are still unknown.

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