scholarly journals Standardization of Malaysian Adult Female Nasal Cavity

2013 ◽  
Vol 2013 ◽  
pp. 1-11 ◽  
Author(s):  
Chih Fang Lee ◽  
Mohd. Zulkifly Abdullah ◽  
Kamarul Arifin Ahmad ◽  
Ibrahim Lutfi Shuaib
Keyword(s):  
Nasal Cavity ◽  
Average Velocity ◽  
Fluid Dynamic ◽  
Cfd Analysis ◽  
Sectional Area ◽  
Cavity Model ◽  
Cross Sectional ◽  
New Approach ◽  
Nasal Cavities ◽  
Preliminary Study

This research focuses on creating a standardized nasal cavity model of adult Malaysian females. The methodology implemented in this research is a new approach compared to other methods used by previous researchers. This study involves 26 females who represent the test subjects for this preliminary study. Computational fluid dynamic (CFD) analysis was carried out to better understand the characteristics of the standardized model and to compare it to the available standardized Caucasian model. This comparison includes cross-sectional areas for both half-models as well as velocity contours along the nasal cavities. The Malaysian female standardized model is larger in cross-sectional area compared to the standardized Caucasian model thus leading to lower average velocity magnitudes. The standardized model was further evaluated with four more Malaysian female test subjects based on its cross-sectional areas and average velocity magnitudes along the nasal cavities. This evaluation shows that the generated model represents an averaged and standardized model of adult Malaysian females.

Acoustic rhinometry in dog and cat compared with a fluid-displacement method and magnetic resonance imaging

2003 ◽  
Vol 95 (2) ◽  
pp. 635-642 ◽  
Author(s):  
Sune P. Straszek ◽  
Finn Taagehøj ◽  
Søren Graff ◽  
Ole F. Pedersen
Keyword(s):  
Magnetic Resonance ◽  
Nasal Cavity ◽  
Complex Structure ◽  
Cross Sectional Area ◽  
Acoustic Rhinometry ◽  
Sectional Area ◽  
Displacement Method ◽  
Cross Sectional ◽  
Fluid Displacement ◽  
Nasal Cavities

An increasing number of studies have used acoustic rhinometry (AR) for study of pharmacological interventions on nasal cavity dimensions in dogs and cats, but there have been no attempts to validate AR in these species. This is done in the present study. We compared area-distance relationships of nasal cavities from five decapitated dogs (3.5–41 kg) and cats (3.8–6 kg). AR was compared with magnetic resonance (MR) imaging and a fluid-displacement method (FDM) using perfluorocarbon. AR measured 88% (98–79%) (mean and 95% confidence interval) of nasal cavity volume in dogs determined by FDM and 71% (83–59%) in cats. AR markedly underestimated nasal cavity dimensions when minimum areas were below 0.1 cm2 in dogs and 0.05 cm2 in cats. AR underestimation increased with the severity of the constriction and with distance. Cross-sectional areas in the deeper parts of the cavity measured 76% (99–54%) of FDM in dogs and 52% (66–39%) in cats. AR agreed well with MR, especially in the deeper part of the cavity. MR images showed that the nasal cavities had a very complex structure not expected to be reproduced by AR. MR could not be considered a “gold standard” because definition of the cross-sectional area of the lumen depended critically on subjective choices. FDM produced repeatable measurements and possibly offers the most adequate reference in future evaluation of AR. AR underestimated what we believed were the most correct cross-sectional areas determined by FDM, especially in the deeper part of the dog and cat nasal cavities. Despite these difficulties, AR has been shown to be useful to describe qualitative changes in cross-sectional area.

Applications of Acoustic Rhinometry in the Modeling of Living Human Nasal Cavity Based on CT Scan

2005 ◽  
Author(s):  
Yingxi Liu ◽  
Jun Zhang ◽  
Xiuzhen Sun
Keyword(s):  
Nasal Cavity ◽  
Fluid Dynamic ◽  
Upper Airway ◽  
Acoustic Rhinometry ◽  
Cavity Model ◽  
Cfd Model ◽  
Cross Sectional ◽  
Significant Information ◽  
3 Dimensional ◽  
Computed Tomography Scans

Acoustic rhinometry can quantify upper airway condition of air draft by drawing a graph plotting the distance from the nostril vs. the cross-sectional area. Some decrease on the graph corresponds to the typical anatomic structures of human nasal cavity. The 3-dimensional, computing fluid dynamic model of the same person was developed based on computed tomography scans. The veracity of the CFD model were valued by contrasting the relevant areas of stenosis site between the model and the AR graph. The aim in this study is to make clear how to use an AR to help improve and enrich the CFD model with the information of graph acquired from the measurement. The combination of AR and CT can be used to establish a living human nasal cavity model with higher significant information content.

Changes in the parameters of nasal breathing and parameters of the upper respiratory tract during orthognathic operations in patients with II and III skeletal class of jaw anomalies

2020 ◽  
pp. 22-27
Author(s):  
S.Sh. Gammadaeva ◽  
M.I. Misirkhanova ◽  
A.Yu. Drobyshev
Keyword(s):  
Respiratory Tract ◽  
Nasal Cavity ◽  
Nasal Septum ◽  
Cross Sectional Area ◽  
Upper Respiratory Tract ◽  
Sectional Area ◽  
Nasal Breathing ◽  
Cross Sectional ◽  
Skeletal Class ◽  
Upper Respiratory

The study analyzed the functional parameters of nasal breathing, linear parameters of the nasal aperture, nasal cavity and nasopharynx, volumetric parameters of the upper airways in patients with II and III skeletal class of jaw anomalies before and after orthognathic surgery. The respiratory function of the nose was assessed using a rhinomanometric complex. According to rhinoresistometry data, nasal resistance and hydraulic diameter were assessed. According to the data of acoustic rhinometry, the minimum cross-sectional area along the internal valve, the minimum cross-sectional area on the head of the inferior turbinate and nasal septum and related parameters were estimated. According to the CBCT data, the state of the nasal septum, the inferior turbinates, the nasal aperture, the state of the nasal cavity, and the linear values of the upper respiratory tract (nasopharynx) were analyzed. The patients were divided into 4 groups according to the classification of the patency of the nasal passages by

Evaluation of Nasal Passage Patency after Antigen and Histamine Challenge in Guinea Pigs by Acoustic Rhinometry

1997 ◽  
Vol 11 (1) ◽  
pp. 85-90 ◽  
Author(s):  
Setsuo Nakamoto ◽  
Yasuo Sakakura ◽  
Ole F. Pedersen ◽  
Kotaro Ukai
Keyword(s):  
Nasal Cavity ◽  
Guinea Pigs ◽  
Airway Resistance ◽  
Cross Sectional Area ◽  
Nasal Passage ◽  
Nasal Airway ◽  
Sectional Area ◽  
Cross Sectional ◽  
Percent Change ◽  
Nasal Airway Resistance

We investigated the effects of antigen and histamine on the nasal passage patency in guinea pigs with or without nasal allergy. The change of nasal patency was measured by acoustic rhinometry and nasal airway resistance. Acoustic reflections have been used in adult humans to determine nasal cavity dimensions in terms of cross-sectional areas as a function of the distance from the nostril. In order to measure nasal cavity dimensions in guinea pigs, we modified equipment for use in humans by decreasing sound tube dimensions, increasing sampling frequency, and applying a special nosepiece. The percent change of volume, minimum cross-sectional area, and nasal airway resistance showed the largest changes at 10 minutes after antigen challenge in sensitized guinea pigs. There was a significant correlation between the individual percent change of nasal airway resistance and volume or minimum cross-sectional area. Histamine, 102 to 105 μg/mL, caused a dose-dependent reduction in percent change of volume in the challenged side of nonsensitized guinea pigs, but not in the opposite side. These results indicate that the noninvasive acoustic reflections technique is useful in small experimental animals, especially to assess the effect of nasal cavity dimensions after the challenge of antigen or nonspecific stimuli.

Hemodynamic Measurements in Human Arterial Casts, and Their Correlation With Histology and Luminal Area

1980 ◽  
Vol 102 (3) ◽  
pp. 247-251 ◽  
Author(s):  
M. H. Friedman ◽  
C. B. Bargeron ◽  
G. M. Hutchins ◽  
F. F. Mark ◽  
O. J. Deters
Keyword(s):  
Laser Doppler Anemometer ◽  
Longitudinal Variation ◽  
Sectional Area ◽  
Vascular Response ◽  
Velocity Measurements ◽  
Cross Sectional ◽  
New Approach ◽  
Flow Acceleration ◽  
Luminal Area ◽  
Hemodynamic Measurements

A new approach is presented for studying the vascular response to hemodynamic stress. A laser doppler anemometer is used to make velocity measurements very near the walls of human arterial casts; these measurements are then correlated with the histology of the artery from which the cast was made. Several illustrative results are given which suggest that the velocity profiles along the outer walls of aortic bifurcations may be significantly determined by the longitudinal variation of cross-sectional area. The shapes of these profiles were qualitatively different for each cast studied. In one specimen, the location of initial lipid deposits appeared to correlate with flow acceleration.

Effects of the Breathe Right Nasal Strips on Nasal Ventilation

1997 ◽  
Vol 11 (5) ◽  
pp. 399-402 ◽  
Author(s):  
Jan Gosepath ◽  
Wolf J. Mann ◽  
Ronald G. Amedee
Keyword(s):  
Nasal Cavity ◽  
Physical Performance ◽  
Cross Sectional Area ◽  
Acoustic Rhinometry ◽  
Sectional Area ◽  
Nasal Breathing ◽  
Cross Sectional ◽  
Subjective Impression ◽  
Breathe Right Nasal Strips ◽  
And Training

The Breathe Right nasal strips are more and more commonly used, mainly by athletes, who hope to enhance their physical performance in competition and training. The effect of the device in such situations is uncertain and perhaps somewhat controversial. To investigate the effects of the nasal strips on nasal ventilation, 20 Caucasian individuals were objectively assessed using anterior rhinomanometry and acoustic rhinometry. The results showed a significant increase in all subjects of transnasal airflow and in the average cross-sectional area of the nasal cavity that quantifies objectively the subjective impression of improved nasal breathing. In such patients where an improvement in nasal ventilation is desired, the use of the Breathe Right nasal strips seems to offer a beneficial treatment.

scholarly journals A comparison of minimal cross sectional areas, nasal volumes and peak nasal inspiratory flow between patients with obstructive sleep apnea and healthy controls

2016 ◽  
Vol 54 (4) ◽  
pp. 342-347
Author(s):  
M.H.S. Moxness ◽  
V. Bugten ◽  
W.M. Thorstensen ◽  
S. Nordgard ◽  
G. Bruskeland
Keyword(s):  
Nasal Cavity ◽  
Inspiratory Flow ◽  
Cross Sectional Area ◽  
Healthy Controls ◽  
Sectional Area ◽  
Cavity Volume ◽  
Cross Sectional ◽  
The Mean ◽  
And Function ◽  
Peak Nasal Inspiratory Flow

Background: The differences in nasal geometry and function between OSA patients and healthy individuals are not known. Our aim was to evaluate the differences in nasal geometry and function using acoustic rhinometry (AR) and peak nasal inspiratory flow (PNIF) between an OSA population and healthy controls. Methodology: The study was designed as a prospective case-control study. Ninety-three OSA patients and 92 controls were enrolled from 2010 to 2015. The minimal cross-sectional area (MCA) and the nasal cavity volume (NCV) in two parts of the nose (MCA0-3/NCV0-3 and MCA3-5.2/NCV3-5.2) and PNIF were measured at baseline and after decongestion. Results: The mean MCA0-3 in the OSA group was 0.49 cm2; compared to 0.55 cm2 in controls. The mean NCV0-3 correspondingly was 2.51 cm3 compared to 2.73 cm3 in controls. PNIF measured 105 litres/minute in the OSA group and 117 litres/minute in the controls. Conclusions: OSA patients have a lower minimum cross-sectional area, nasal cavity volume and peak inspiratory flow compared to controls. Our study supports the view that changes in the nasal cavity may contribute to development of OSA.

Pumping Loss of Shrouded Meshed Spur Gears

2020 ◽  
Author(s):  
Michael J. Hurrell ◽  
Jerzy T. Sawicki
Keyword(s):  
High Speed ◽  
Fluid Dynamic ◽  
Spur Gear ◽  
Test Facility ◽  
Spur Gears ◽  
Cfd Analysis ◽  
Total Load ◽  
New Approach ◽  
Loss Component ◽  
Swept Volume

Abstract High speed rotorcraft transmissions are subject to load-independent power losses consisting of drag loss and pumping loss. Tightly conforming shrouds enclosing the transmission gears are often incorporated to reduce the drag component of the total load-independent losses. However, tightly conforming axial shrouds can result in an increase in the pumping loss component. Quantifying the pumping loss of shrouded gear transmissions has been the subject of many studies. This study presents a new approach for estimating pumping loss based on the concept of swept volume and examines the applicability of the approach to various shroud configurations. The drag loss and pumping loss of a shrouded spur gear pair has been determined through testing using the NASA Glenn Research Center (GRC) Gear Windage Test Facility. The results from this testing have been compared to theoretical results using the formulations presented in this study. In addition, computational fluid dynamic (CFD) analysis has been conducted for the various shroud configurations tested at NASA GRC. The results from the CFD analysis confirm the theoretical and empirical results and provide insight into the applicability of the swept volume approach for estimating pumping power loss of shrouded gear transmissions.

scholarly journals Assessment of changes in the nasal airway after nonsurgical miniscrew-assisted rapid maxillary expansion in young adults

2018 ◽  
Vol 88 (4) ◽  
pp. 435-441 ◽  
Author(s):  
Soo-Yeon Kim ◽  
Young-Chel Park ◽  
Kee-Joon Lee ◽  
Andreas Lintermann ◽  
Sang-Sun Han ◽  
...  
Keyword(s):  
Young Adults ◽  
Nasal Cavity ◽  
Rapid Maxillary Expansion ◽  
Cross Sectional Area ◽  
Nasal Airway ◽  
Sectional Area ◽  
Maxillary Expansion ◽  
Cross Sectional ◽  
T1 And T2 ◽  
Observation Period

ABSTRACT Objectives: To evaluate changes in the volume and cross-sectional area of the nasal airway before and 1 year after nonsurgical miniscrew-assisted rapid maxillary expansion (MARME) in young adults. Materials and Methods: Fourteen patients (mean age, 22.7 years; 10 women, four men) with a transverse discrepancy who underwent cone beam computed tomography before (T0), immediately after (T1), and 1 year after (T2) expansion were retrospectively included in this study. The volume of the nasal cavity and nasopharynx and the cross-sectional area of the anterior, middle, and posterior segments of the nasal airway were measured and compared among the three timepoints using paired t-tests. Results: The volume of the nasal cavity showed a significant increase at T1 and T2 (P < .05), while that of the nasopharynx increased only at T2 (P < .05). The anterior and middle cross-sectional areas significantly increased at T1 and T2 (P < .05), while the posterior cross-sectional area showed no significant change throughout the observation period (P > .05). Conclusions: The results demonstrate that the volume and cross-sectional area of the nasal cavity increased after MARME and were maintained at 1 year after expansion. Therefore, MARME may be helpful in expanding the nasal airway.

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