Airway Dimensions (airway + dimension)

Distribution by Scientific Domains


Selected Abstracts


Longitudinal study of airway dimensions in chronic obstructive pulmonary disease using computed tomography

RESPIROLOGY, Issue 3 2008
Tadashi OHARA
Background and objective: Chest CT has been widely used for the evaluation of structural changes in lung parenchyma and airways in cross-sectional studies. There has been no report on the annual changes in airway dimensions as assessed by CT in COPD patients. The objective of this study was to investigate the annual changes in airway dimensions and lung attenuation using CT in patients with COPD and to evaluate the correlations among annual changes in CT measurements and pulmonary function. Methods: Eighty-three men with COPD had completed five annual assessments of CT scans and pulmonary function tests over 4 years. Airway dimensions of the basal segment bronchi and lung attenuation on CT images were analysed in 38 subjects in whom the same airway could be measured at least three times, including at entry and at the end of the study. Results: Mean annual decline in FEV1 was 21 mL/year. Annual changes in the percentage of low attenuation areas were not significantly correlated with decline in FEV1. On the other hand, annual changes in the percentage of wall area (WA%/year) were significantly inversely correlated with annual changes in FEV1 (r = ,0.363, P = 0.025), whereas WA%/year did not differ among severity stages at entry and did not correlate with baseline FEV1. Conclusions: The results showing that annual changes in airway thickening correlated with annual decline in air flow limitation suggests the importance of treatment of airway inflammation in COPD. CT is a useful tool for quantitative estimation not only of emphysema but also of airway lesions in longitudinal studies. [source]


Airway Assessment by Volumetric Computed Tomography in Snorers and Subjects With Obstructive Sleep Apnea in a Far-East Asian Population (Chinese)

THE LARYNGOSCOPE, Issue 4 2002
Ning-Hung Chen MD
Abstract Objectives To evaluate the airway dimension of simple snorers and subjects with obstructive sleep apnea (OSA) in a Far-East Asian population (Chinese). Study Design Prospective study of 117 near-consecutive patients evaluated for snoring and possible OSA from January 1998 to December 1998 in a sleep laboratory. Overnight polysomnography (PSG) was performed on all patients and the sleep parameters, including respiratory disturbance index (RDI), snoring index, minimal oxygen saturation (min O2), percentage of slow wave sleep (SWS), and rapid eye movement (REM) were recorded. Three-dimensional computerized tomography (CT) during awake periods was performed. The anteroposterior (AP) and the lateral distance of the retropalatal (RP) region in the oropharynx, the smallest area of RP, and retroglossal (RG) regions, and the total volume of the oropharynx were measured. Result Ninety-eight patients were diagnosed with OSA (mean RDI, 41.48 ± 26.45 events per hour; min O2, 72.82 ± 12.86%), whereas 19 were simple snorers. The AP and the lateral distance of the RP region, as well as the smallest area of the RP region, are significantly smaller in subjects with OSA. However, no differences in the RG region and the total volume of the oropharynx were found between the two groups. Linear regression analysis demonstrated that the lateral dimension and the smallest RP area in overweight subjects inversely correlated with the RDI, but only the AP dimension of the RP area was found to have an inverse correlation with the RDI in the underweight subjects. Conclusion In Far-East Asians (Chinese), the RP airway was found to be the primary site of narrowing in subjects with OSA, and the narrowest RP area was inversely correlated with RDI. Furthermore, weight may influence the pattern of RP narrowing by contributing to lateral collapse. [source]


Longitudinal study of airway dimensions in chronic obstructive pulmonary disease using computed tomography

RESPIROLOGY, Issue 3 2008
Tadashi OHARA
Background and objective: Chest CT has been widely used for the evaluation of structural changes in lung parenchyma and airways in cross-sectional studies. There has been no report on the annual changes in airway dimensions as assessed by CT in COPD patients. The objective of this study was to investigate the annual changes in airway dimensions and lung attenuation using CT in patients with COPD and to evaluate the correlations among annual changes in CT measurements and pulmonary function. Methods: Eighty-three men with COPD had completed five annual assessments of CT scans and pulmonary function tests over 4 years. Airway dimensions of the basal segment bronchi and lung attenuation on CT images were analysed in 38 subjects in whom the same airway could be measured at least three times, including at entry and at the end of the study. Results: Mean annual decline in FEV1 was 21 mL/year. Annual changes in the percentage of low attenuation areas were not significantly correlated with decline in FEV1. On the other hand, annual changes in the percentage of wall area (WA%/year) were significantly inversely correlated with annual changes in FEV1 (r = ,0.363, P = 0.025), whereas WA%/year did not differ among severity stages at entry and did not correlate with baseline FEV1. Conclusions: The results showing that annual changes in airway thickening correlated with annual decline in air flow limitation suggests the importance of treatment of airway inflammation in COPD. CT is a useful tool for quantitative estimation not only of emphysema but also of airway lesions in longitudinal studies. [source]


Stochastic Morphometric Model of the Balb/c Mouse Lung

THE ANATOMICAL RECORD : ADVANCES IN INTEGRATIVE ANATOMY AND EVOLUTIONARY BIOLOGY, Issue 10 2010
Pierre Madl
Abstract The laboratory mouse is often used as a human surrogate in aerosol inhalation studies. Morphometric data on the tracheobronchial geometry of three in situ lung casts of the Balb/c mouse lung produced by the Air Pollution Health Effects Laboratory were analyzed in terms of probability density functions and correlations among the different airway parameters. The results of this statistical analysis reveal significant differences in diameters and branching angles between major and minor progeny branching off from the same parent airway at a given airway bifurcation. Number of bronchial airways generations along a given path, expressed by the termination probability, branching angles, and daughter-to-parent diameter ratios indicate that the location of an airway with defined linear airway dimensions within the lung is more appropriately identified by its diameter (or its parent diameter) than by an assigned generation number. We, therefore, recommend classifying the mouse lung airways by their diameters and not by generation numbers, consistent with our previous analysis of the rather monopodial structure of the rat lung (Koblinger et al., J Aerosol Med 1995;8:7,19; Koblinger and Hofmann, J Aerosol Med 1995;8:21,32). Because of lack of corresponding information on respiratory airways, a partly stochastic symmetric acinar airway model was attached to the tracheobronchial model, in which the number of acinar airways along a given path was randomly selected from a measured acinar volume distribution. The computed distributions of the geometric airway parameters and their correlations will be used for random pathway selection of inhaled particles in subsequent Monte Carlo deposition calculations. Anat Rec 293:1766,1786, 2010. © 2010 Wiley-Liss, Inc. [source]


Objective Sizing of Upper Airway Stenosis: A Quantitative Endoscopic Approach,

THE LARYNGOSCOPE, Issue 1 2006
MBBChir, S. A. R. Nouraei MA
Abstract Objective: In patients with airway stenosis, anatomy of the lesion determines the magnitude of the biomechanical ventilatory disturbance and thus the nature and severity of symptoms. It also gives information about biology, likelihood of response to treatment, and prognosis of laryngotracheal lesions. Accurate airway sizing throughout treatment is therefore central to managing this condition. We developed a method for objective assessment of airway lesions during endoscopy. Methods: We used airway simulations to investigate the effects of endoscope tilt and lens distortions on measurement accuracy, devising and validating clinical rules for quantitative airway endoscopy. A calibrator was designed to assess lesion length, location, and cross-section during tracheoscopy. Results: It proved possible to calculate the length and location of the stenosis using simple mathematics. Cross-section measurements were more than 95% accurate, independent of endoscope tilt and without making assumptions about endoscope optics and visuospatial distortion, for both pediatric and adult airway dimensions. The technique was used to characterize airway lesions in 10 adult patients with an average age of 48 years undergoing therapeutic laryngotracheoscopy. Lesions occurred on average 36 mm below the glottis (range, 21,54 mm) and were 9.3 mm long (5,17 mm). The average pretreatment airway cross-section was 48.3 mm2, increasing to 141.1 mm2 after laser therapy. Two independent observers calculated airway cross-sections, achieving an interobserver concordance of 0.98. Conclusions: This method can be used to objectively and precisely determine the anatomy of airway lesions, allowing accurate documentation of lesion characteristics and surgical results, serial monitoring throughout treatment, and comparison of outcomes between different centers. [source]