scholarly journals Novel three-dimensional methods to analyze the morphology of the nasal cavity and pharyngeal airway

2021 ◽  
Author(s):  
Xiaowen Niu ◽  
Sivaranjani Madhan ◽  
Marie A. Cornelis ◽  
Paolo M. Cattaneo
Keyword(s):  
Nasal Cavity ◽  
Measurement Errors ◽  
Intraclass Correlation ◽  
Three Dimensional ◽  
The Novel ◽  
Cross Sectional ◽  
Pharyngeal Airway ◽  
Semiautomatic Segmentation ◽  
Bland Altman Method ◽  
Level Of Agreement

ABSTRACT Objectives To assess the intraexaminer and interexaminer reliabilities of novel semiautomatic methods to segment the nasal cavity (NC) and pharyngeal airway (PA) and to determine the minimal cross-sectional area (CS) and hydraulic diameter (HD) of the PA. Materials and Methods To test reproducibility, two examiners analyzed the NC and PA independently in 10 retrospectively selected cone beam computed tomography (CBCT) images using semiautomatic segmentation. The PA centerline was determined to assess the minimal CS and HD. The intraclass correlation coefficient (ICC) was used to calculate intraexaminer and interexaminer reliabilities. Measurement errors were assessed by Dahlberg's formula and paired t-tests. The level of agreement was assessed using the Bland-Altman method. Results Intraexaminer and interexaminer reliabilities were excellent (minimal ICC, 0.960). The error of the method was good except for interexaminer values for the oropharynx (P = .016). The minimal CS and HD measurements were reliable (minimal ICC, 0.993; narrow limits of agreement). Conclusions The novel methods for analysis of the NC and PA are reliable. The minimal CS and HD demonstrated excellent reliabilities, which are critical to detect the most constricted part of the PA. Separation of the oropharynx from the voids close to the retroglossal area is not trivial and should be considered with caution.

scholarly journals Interdevice agreement in respiratory resistance values by oscillometry in asthmatic children

2019 ◽  
Vol 5 (1) ◽  
pp. 00138-2018 ◽  
Author(s):  
Francine M. Ducharme ◽  
Imane Jroundi ◽  
Guillaume Jean ◽  
Guillaume Lavoie Boutin ◽  
Christiane Lawson ◽  
...  
Keyword(s):  
Intraclass Correlation ◽  
Random Order ◽  
Cross Sectional Study ◽  
Normative Values ◽  
Impulse Oscillometry ◽  
Respiratory Resistance ◽  
Sectional Study ◽  
Cross Sectional ◽  
Asthmatic Children ◽  
Bland Altman Method

BackgroundWith several commercially available devices measuring respiratory impedance by oscillometry, the agreement between values obtained on different instruments or frequencies remains unclear. Our aim was to examine the agreement between resistance and reactance parameters on two oscillometry instruments using different waveforms.MethodsWe conducted a prospective cross-sectional study in asthmatic children aged 3–17 years. Reproducible oscillometry measurements were obtained in random order, by blinded operators, at three modes: 5–10–15–20–25 Hz (5–25 Hz) multifrequency mode on the MasterScreen impulse oscillometry system, and both 5–25 Hz multifrequency mode and 7 Hz monofrequency on the tremoFlo C-100 airwave sinusoidal system. Resistance, reactance and within-breath parameters were examined using the intraclass correlation coefficient (ICC), paired t-test, linear regression and Bland–Altman method.ResultsOf 50 participants, 44 and 38 completed between-device and within-frequency measurements, respectively. Between-device measurements at 5–25 Hz showed high (ICC 0.88–0.91) and good (ICC 0.69–0.87) agreement in resistance and reactance, respectively, but with an absolute within-patient difference (≥0.05 kPa·L−1·s−1) and proportional bias (≥30% per kPa·L−1·s−1) in all parameters and oscillatory frequencies, apart from resistance at 5 Hz. A significant proportional bias was documented in most within-breath parameters at 5 versus 7 Hz on tremoFlo.ConclusionObserved differences in resistance and reactance suggest the need for instrument- and frequency-specific paediatric normative values.

The Identification of the Potential Limitations of Acoustic Rhinometery Using Computer-Generated, Three-Dimensional Reconstructions of Simple Models

1996 ◽  
Vol 10 (2) ◽  
pp. 77-82 ◽  
Author(s):  
A. Tomkinson ◽  
R. Eccles
Keyword(s):  
Nasal Cavity ◽  
Three Dimensional ◽  
Internal Surface ◽  
Three Dimensions ◽  
Gradual Change ◽  
Large Area ◽  
Cross Sectional ◽  
Wave Path ◽  
Acoustic Evaluation ◽  
Set Up

The internal surface of the nasal cavity is geometrically complicated and does not lend itself readily to direct measurement. Simple geometric shapes were used as a model for changes in the nasal cavity. Following the introduction of specific changes to a particular system, the effect of these changes on the acoustic evaluation of the space was studied. Cylinders were chosen, as the wave path could be assumed to be perpendicular to the model surface. The acoustic rhinometer's accuracy was assessed in the presence of small and large variations in cross sectional area, in the presence of a series of consecutive area changes, and a gradual change in diameter. The effect of the introduction of acoustic leak was also modelled. The acoustic data acquired from these models was used to reconstruct the model in three dimensions. These reconstructions were compared to the original model. The acoustic rhinometer was found to resolve with reasonable accuracy the dimensions of small spaces; however, if regions of sudden large area changes were present in the space, the data beyond these regions was highly unreliable. Furthermore, the presence of acoustic leak in a system had a similar effect. Unless precautions are taken in the set-up and operation of the acoustic rhinometer, the potential for misinterpretation of data and the introduction of bias is very high.

Determination of Facial Symmetry in Unilateral Cleft Lip and Palate Patients from Three-Dimensional Data: Technical Report and Assessment of Measurement Errors

2006 ◽  
Vol 43 (2) ◽  
pp. 129-137 ◽  
Author(s):  
Emeka Nkenke ◽  
Bernhard Lehner ◽  
Manuel Kramer ◽  
Gerd Haeusler ◽  
Stefanie Benz ◽  
...  
Keyword(s):  
Measurement Errors ◽  
Cleft Lip ◽  
Cleft Lip And Palate ◽  
Intraclass Correlation ◽  
Three Dimensional ◽  
Correlation Coefficients ◽  
Intraclass Correlation Coefficients ◽  
Surface Areas ◽  
Technical Report

Objective To assess measurement errors of a novel technique for the three-dimensional determination of the degree of facial symmetry in patients suffering from unilateral cleft lip and palate malformations. Design Technical report, reliability study. Setting Cleft Lip and Palate Center of the University of Erlangen-Nuremberg, Erlangen, Germany. Patients The three-dimensional facial surface data of five 10-year-old unilateral cleft lip and palate patients were subjected to the analysis. Distances, angles, surface areas, and volumes were assessed twice. Main Outcome Measures Calculations were made for method error, intraclass correlation coefficient, and repeatability of the measurements of distances, angles, surface areas, and volumes. Results The method errors were less than 1 mm for distances and less than 1.5° for angles. The intraclass correlation coefficients showed values greater than .90 for all parameters. The repeatability values were comparable for cleft and noncleft sides. Conclusion The small method errors, high intraclass correlation coefficients, and comparable repeatability values for cleft and noncleft sides reveal that the new technique is appropriate for clinical use.

scholarly journals Risk factors for small pharyngeal airway dimensions in preorthodontic children: A three-dimensional study

2016 ◽  
Vol 87 (1) ◽  
pp. 138-146 ◽  
Author(s):  
Seerone Anandarajah ◽  
Raahib Dudhia ◽  
Andrew Sandham ◽  
Liselotte Sonnesen
Keyword(s):  
Skeletal Maturity ◽  
Three Dimensional ◽  
Cross Sectional Area ◽  
Craniofacial Morphology ◽  
Sectional Area ◽  
Cross Sectional ◽  
Pharyngeal Airway ◽  
And Gender ◽  
Relevant Factors ◽  
Airway Dimensions

ABSTRACT Objective: To analyze which parameters, gathered from standard orthodontic diagnostic material, were most relevant for identifying small pharyngeal airway dimensions in preorthodontic children. Materials and Methods: The sample was composed of 105 cone beam computed tomography scans of healthy preorthodontic children (44 boys, 61 girls; mean age, 10.7 ± 2.4 years). Airway volume and minimal cross-sectional area were three-dimensionally assessed. Cephalometric features and skeletal maturity were assessed on generated two-dimensional cephalograms. Associations were analyzed and adjusted for age, gender, and skeletal maturity by multiple regression analyses. Results: Airway volume and minimal cross-sectional area were significantly smaller in prepubertal children (P < .001, P < .05, respectively) and positively associated with age (P < .001, P < .01, respectively). After adjustment of age, skeletal maturity and gender significant associations were found between pharyngeal airway dimensions and craniofacial morphology. Airway volume was positively associated with maxillary and mandibular width (P < .01; P < .001, respectively) and anterior face height (P < .05; P < .05, respectively). Minimal cross-sectional area was positively associated with maxillary and mandibular width (P < .01; P < .001, respectively) and negatively associated with sagittal jaw relationship (AnPg, P < .05). Mandibular width and age were the most relevant factors for airway volume (r2 = 0.36). Mandibular width and sagittal jaw relationship were the most relevant factors for minimal cross-sectional area (r2 = 0.16). Conclusion: Pharyngeal airway dimensions were significantly associated with age, skeletal maturity, and craniofacial morphology in all three planes. Children with a reduced mandibular width and increased sagittal jaw relationship are particularly at risk of having small pharyngeal airway dimensions.

Acoustic rhinometry: validation by three-dimensionally reconstructed computer tomographic scans

2000 ◽  
Vol 89 (3) ◽  
pp. 1013-1021 ◽  
Author(s):  
Hendrik Terheyden ◽  
Steffen Maune ◽  
Jürgen Mertens ◽  
Ole Hilberg
Keyword(s):  
Nasal Cavity ◽  
Linear Regression Analysis ◽  
Three Dimensional ◽  
Acoustic Rhinometry ◽  
Single Subject ◽  
Three Dimensional Model ◽  
Head Region ◽  
Cross Sectional ◽  
Air Volume ◽  
Ct Data

The aim of the present study was a validation of acoustic rhinometry (AR) by computed tomography (CT). Six healthy subjects were examined by CT and AR. The CT data were processed in a computer program (AutoCAD), and a virtual three-dimensional model of each nasal cavity was constructed. This model permitted an individual prediction of the center line of the sound wave propagation through the air volume of the nasal cavity with the cross-sectional areas oriented perpendicularly to this line. The area-distance curves derived from AR and CT were compared. Linear regression analysis revealed a reasonable agreement of AR and CT in the anterior nose below a mean of 6 cm distance from the nostrils [ r = 0.839, P < 0.01, m = 1.123, b= −0.113 (AR = m × CT + b)]. The measuring accuracy using CT as gold standard revealed a mean error at the nasal valve of <0.01 cm2 (4.52%) and at the nasal isthmus of 0.02 cm2 (1.87%). Beyond 6 cm, the correlation decreased ( r = 0.419), and overestimation of the true area occurred (>100%). In conclusion, the measurements were reasonably accurate for diagnostic use up to the turbinate head region. Certain factors induce an overestimation of the true areas beyond this region. However, these factors are constant and reproducible in a single subject, and intraindividual comparative measurements are possible beyond the turbinate head region.

Study on Effects of Novel Cross Sections of Microchannel Heat Sink on Thermohydraulic Performance

2020 ◽  
Vol 142 (4) ◽  
Author(s):  
Abhilash K. Tilak ◽  
Ranjit S. Patil
Keyword(s):  
Cross Section ◽  
Cross Sections ◽  
Three Dimensional ◽  
Constant Heat Flux ◽  
Heat Sinks ◽  
Microchannel Heat Sink ◽  
The Novel ◽  
Cross Sectional ◽  
The Heat Transfer Coefficient ◽  
Three Dimensional Simulations

Abstract In this paper, three-dimensional simulations to study the performance of microchannel heat sinks (MCHS) with rectangular, hexagonal, semicircular and various novel cross section (such as barrel, fan shaped, L shaped, inverted T shaped, inverted T shaped with semicircular ends at base (ITSCEB)) were carried out using de-ionized water. Numerical results were validated with the published experimental data and further simulations were performed on various novel cross section at a constant heat flux of 50 W/cm2 with Reynolds number varying in the range of 300–1500. The comparative analysis of various novel MCHS having the same cross-sectional area was carried out to figure out the suitable cross section capable of better cooling performance. This work shows that the novel ITSCEB cross section was giving the highest pressure drop, however considerable improvement was noted in the heat transfer coefficient around 21% more than conventional rectangular and around 11–55% more than other proposed cross section in this study.

Creation of a standardized geometry of the human nasal cavity

2009 ◽  
Vol 106 (3) ◽  
pp. 784-795 ◽  
Author(s):  
Y. Liu ◽  
M. R. Johnson ◽  
E. A. Matida ◽  
S. Kherani ◽  
J. Marsan
Keyword(s):  
Nasal Cavity ◽  
Three Dimensional ◽  
Ct Scans ◽  
Physical Parameters ◽  
Specific Procedure ◽  
Image Processing Algorithm ◽  
Cross Sectional ◽  
Nasal Airways ◽  
Numerical Studies ◽  
Inhaled Aerosols

A novel, standardized geometry of the human nasal cavity was created by aligning and processing 30 sets of computed tomography (CT) scans of nasal airways of healthy subjects. Digital three-dimensional (3-D) geometries of the 60 single human nasal cavities (30 right and 30 mirrored left cavities) were generated from the CT scans and measurements of physical parameters of each single nasal cavity were performed. A methodology was developed to scale, orient, and align the nasal geometries, after which 2-D digital coronal cross-sectional slices were generated. With the use of an innovative image processing algorithm, median cross-sectional geometries were created to match median physical parameters while retaining the unique geometric features of the human nasal cavity. From these idealized 2-D images, an original 3-D standardized median human nasal cavity was created. This new standardized geometry was compared against the original geometries of all subjects as well as limited existing data from the literature. The new model has potential for use as a geometric standard in future experimental and numerical studies of deposition of inhaled aerosols, as well as for use as a reference during diagnosis of unhealthy patients. The specific procedure developed could also be applied to build standard nasal geometries for different identifiable groups within the larger population.

Development and Validation of the Nurse Prescribing Self-Efficacy Scale

2020 ◽  
pp. 019394592096250
Author(s):  
Teresa Galiana-Camacho ◽  
María Dolores Ruiz-Fernandez ◽  
Iria Dobarrio-Sanz ◽  
José Granero-Molina ◽  
Cayetano Fernandez-Sola ◽  
...  
Keyword(s):  
Internal Consistency ◽  
Content Validity ◽  
Self Efficacy ◽  
Intraclass Correlation ◽  
Temporal Stability ◽  
Three Dimensional ◽  
Cross Sectional Study ◽  
Dimensional Structure ◽  
Cross Sectional ◽  
Nurse Prescribing

Low self-efficacy is a barrier to effective nurse prescribing. Therefore, nurses’ self-efficacy should be assessed using validated tools. We aimed to develop and psychometrically test the Nurse Prescribing Self-Efficacy Scale (NP-SES). We conducted an observational cross-sectional study with 290 nurses between January and June 2019. We studied the NP-SES’ reliability (i.e., internal consistency and temporal stability), validity (i.e., content, criterion, and construct) and legibility. The NP-SES showed good internal consistency (Cronbach’s alpha=0.958) and temporal stability (intraclass correlation coefficient=0.783). The NP-SES also showed good content validity (scale’s content validity index=0.98) and criterion validity ( r=0.75; p<0.001). Construct validity analysis revealed the NP-SES’ three-dimensional structure and showed its ability to detect significant differences between nurses with different levels of experience. Our psychometric analysis suggests that the NP-SES is a reliable and valid instrument that could be used to assess nurses’ self-efficacy in nurse prescribing.

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