Airway Narrowing in Healthy Humans Inhaling  Methacholine without Deep Inspirations Demonstrated by HRCT

Brown, Robert H.; Croisille, Pierre; Mudge, Beatrice; Diemer, Fiona B.; Permutt, Solbert; Togias, Alkis

doi:10.1164/ajrccm.161.4.9806051

Cited by 62 publications

(45 citation statements)

References 24 publications

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“…They found a relationship between Rpartial and the change in airway lumen area on HRCT. The disparity between the current findings and those of BROWN et al [8] may have been due to differences in methods of volume standardisation, differences in the magnitude of airway narrowing or differences in airway sizes that were imaged in the current study. Since the measurement of FEV1 requires a deep inspiration, and since it is well documented that deep inspiration can largely reverse airway narrowing in normal subjects [13,25,26], it is not surprising that this measurement did not correlate with HRCT measurements.…”

Section: Discussioncontrasting

confidence: 97%

“…These findings are consistent with narrowing or closure of the large airways (o2 mm diameter) and are concordant with the results of high-resolution computed tomography (HRCT) studies of human airway narrowing [7][8][9]. Although narrowing has been measured in large airways by direct imaging, the evidence for heterogeneous narrowing has been indirect (i.e.…”

supporting

confidence: 84%

“…The partial FEV1/FVC ratio has been described by SKLOOT et al [13] for modified methacholine challenge tests in which deep inspirations were prohibited. It has also been used by BROWN et al [8] once again to study the effects of prohibition of deep inspiration during modified challenges in five normal subjects using HRCT. They found a relationship between Rpartial and the change in airway lumen area on HRCT.…”

Section: Discussionmentioning

confidence: 99%

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Heterogeneity of narrowing in normal and asthmatic airways measured by HRCT

King¹,

Carroll²,

Müller³

et al. 2004

Eur Respir J

100

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Asthmatic airway narrowing is heterogeneous and contributes to airway hyperresponsiveness. The present study compared heterogeneity of narrowing during methacholine challenge in asthmatics and normal subjects using high-resolution computed tomography (HRCT).The current authors defined heterogeneity as variability in narrowing greater than the repeatability of measurement. Airways of v2 mm diameter were compared with larger airways from baseline and postmethacholine HRCT of the right lower lung in 13 normals (seven had repeat baseline scans) and seven asthmatics. The coefficient of repeatability was calculated from repeat scans (RepAi) and was compared with heterogeneity of narrowing measured by the variability in narrowing from pre versus postmethacholine scans (VarDAi).Forced expiratory volume in one second decreased 27¡6% and 24¡8% in normals and asthmatics, respectively. Airways w2 mm narrowed more heterogeneously in asthmatics (VarDAi=¡0.85 mm) compared with normals (VarDAi=¡0.67 mm), with both being greater than the measure of repeatability (RepAi=¡0.16 mm). Small airway narrowing was not heterogeneous in asthmatics (VarDAi=¡0.59 mm) or normals (VarD Ai= ¡0.53 mm) compared with repeatability (RepAi=0.51 mm).It is possible to study heterogeneity of airway narrowing in small and large airways using high resolution computed tomography. Airway narrowing is heterogeneous in the large airways of asthmatics and normals, being greater in asthmatics.

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Section: Discussioncontrasting

confidence: 97%

supporting

confidence: 84%

Section: Discussionmentioning

confidence: 99%

See 1 more Smart Citation

Heterogeneity of narrowing in normal and asthmatic airways measured by HRCT

King¹,

Carroll²,

Müller³

et al. 2004

Eur Respir J

100

View full text Add to dashboard Cite

show abstract

“…BROWN et al [74] measured airway narrowing with increasing concentrations of inhaled methacholine in normal subjects who were prevented from taking a deep inspiration after the methacholine inhalation. They demonstrated airway luminal narrowing and no predilection for greater narrowing in any airway size that could be assessed.…”

Section: Airway Imaging In Asthma Airway Dimensionsmentioning

confidence: 99%

Computed tomographic imaging of the airways: relationship to structure and function

Jong

Müller²,

Paré³

et al. 2005

European Respiratory Journal

156

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Alterations in the structure of the airways, collectively termed airway remodelling, contribute to airflow obstruction in a variety of chronic lung diseases. While histology has provided valuable insights into the structure of airway wall remodelling, this technique is invasive and does not allow the longitudinal analysis of airway wall dimensions. Technical advances in computed tomography allow the assessment of airway wall dimensions, and are ideally suited for the noninvasive investigation of the pathogenesis of airway wall remodelling and the evaluation of new therapeutic interventions. The aim of this article is to review the use of computed tomography in the investigation of airway structure and function in health and disease.

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“…High-resolution computed tomography (HRCT) has been the imaging modality of choice for assessing airways in asthma studies [1][2][3][4][5]. Numerous algorithms have been developed to process the acquired MDCT data [3,[6][7][8][9][10][11][12].…”

Section: Introductionmentioning

confidence: 99%

Investigation of Hyperpolarized 3He Magnetic Resonance Imaging Utility in Examining Human Airway Diameter Behavior in Asthma Through Comparison with High-Resolution Computed Tomography

Tzeng¹,

Hoffman²,

Cook-Granroth³

et al. 2008

Academic Radiology

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Rationale and Objectives-Application of a previously developed model-based algorithm on hyperpolarized (HP) 3 He MR dynamic projection images of phantoms was extended to investigate the utility of HP 3 He MRI in quantifying airway caliber change associated with asthma.Materials and Methods-Airways of seven volunteers were imaged and measured using HP 3 He MRI and multidetector-row computed tomography (MDCT) before and after a methacholine (MCh) challenge. MDCT data was obtained at functional residual capacity (FRC) and one liter above FRC (FRC+1L).Results-Comparison of the resultant data showed that HP 3 He MRI did not match MDCT in measuring the ratios of airway calibers before and after the MCh challenge in 37%-43% of the airways from the first six generations at the two lung volumes tested. However, MDCT did lead to the observation that 49%-69% of these airways displayed bronchodilation following MCh challenge. Conclusion-The current implementation of HP 3 He MRI did not match the MCh-induced postchallenge to pre-challenge airway caliber ratios as measured with MDCT. Elevated parenchymal tethering due to bronchoconstriction-induced hyperinflation was proposed as a possible explanation for this airway dilation.

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Airway Narrowing in Healthy Humans Inhaling Methacholine without Deep Inspirations Demonstrated by HRCT

Cited by 62 publications

References 24 publications

Heterogeneity of narrowing in normal and asthmatic airways measured by HRCT

Heterogeneity of narrowing in normal and asthmatic airways measured by HRCT

Computed tomographic imaging of the airways: relationship to structure and function

Investigation of Hyperpolarized 3He Magnetic Resonance Imaging Utility in Examining Human Airway Diameter Behavior in Asthma Through Comparison with High-Resolution Computed Tomography

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