Comparison of micro-CT parameters.

<p>A) Total lung attenuation, B) peribronchial mean attenuation (PBA), and C) normalized PBA are presented for control (white box plots) and OVA-sensitized (grey box plots) mice at each endpoint. Box plots summarise medians with 25% and 75% interquartiles. Error bars represent 5th and 95th percentiles. *p<0.05 using Wilcoxon’s signed-rank tests between control and OVA.</p

Comparison of Penh and lung resistance.

<p>A) Bronchial hyperresponsiveness (BHR) to methacholine was determined at Day 75 in unrestrained conscious mice by single-chamber plethysmography. The results were expressed as a ratio of Penh measured in response to 8 mg/ml methacholine to that with normal saline. B) Bronchial hyperresponsiveness (BHR) to methacholine was also determined at Day 77 in anaesthetised and intubated animals by invasive plethysmography. The results were expressed as a ratio of LR measured in response to 8 mg/ml methacholine to that with normal saline. Results from control (white bars) and OVA-sensitized mice (black bars) are presented.</p

Description of the 3 asthmatic mouse models.

<p>Data are means ± standard error of the mean. P-values were obtained using Wilcoxon-Mann-Whitney rank sum test. BAL: bronchoalveolar lavage.</p

Correlation matrix between micro-CT bronchial parameters and plethysmographic, BAL and histological data.

<p>Data are Spearman rank correlation coefficients. Data in parentheses are P-values.</p><p>BAL: bronchoalveolar lavage. PBA: peribronchial mean attenuation, Normalized PBA corresponds to 1– PBA/total lung mean attenuation.</p

Bland-Altman analysis of manual and semi-automatic methods for peribronchial attenuation (PBA) measurements.

<p>A) Correlation of peribronchial mean attenuation (PBA) between the two methods. Dashed line represents the line of equality. Solid line corresponds to the regression line. B) Means of measurement between the two methods are plotted against their differences. Solid line corresponds to the mean difference. Dashed lines correspond to the mean difference ±2 standard deviations. C) Means of measurement between the two methods are plotted against their standard deviations.</p

Semi-automatic 3D method for assessing peribronchial attenuation.

<p>A) Native axial (top) and coronal thin-section reformatted (bottom) micro-CT images of the bronchial tree. B) Automatic segmentation of the bronchial lumen (pink). C) Automatic 8-voxels dilatation of the lumen volume. D) Second automatic segmentation of the bronchial lumen volume (green) overwriting bronchial lumen from the previous volume of interest. E) After subtraction of the bronchial lumen, the resultant volume of interest includes only the peribronchial area of the whole bronchial tree. From the created peribronchial volume, the software provides the peribronchial mean attenuation (PBA) value.</p

Typical axial native micro-CT images of control (left) and OVA-sensitized mice (right) at different endpoints: A) Day 36, B) Day 76 and C) Day 111.

<p>The insert at the right bottom of each panel corresponds to a selected part of a new image generated by normalizing each pixel attenuation value by the total lung attenuation value. The green circles delineating the lumen and the 8-voxels peribronchial atmosphere help to demonstrate the differences in normalized peribronchial attenuation between control and OVA-sensitized mice at day 76 and day 111.</p

Typical coronal curved reformatted micro-CT images of the bronchial tree with numerical values of peribronchial mean attenuation (PBA) and normalized PBA.

<p>Images were obtained from control mice (left) and OVA-sensitized (right) at different endpoints: A) Day 36, B) Day 76 and C) Day 111.</p