COPD Flip part 1
JK Amorosa
Emphysema
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Centriacinar (centrilobular)
Panlobular
Paraseptal
Irregular
Emphysema definitions
• Centriacinar: cigarette smoking, upper lobes
Dilitation second order respiratory
bronchioles, respiratory bronchiolitis may be
precursor
Panlobular: lower lobes, involves entire
lobule, seen in senile emphysema and alpha-1antiprotease deficiency
• Paraseptal: involves periphery of secondary
pulmonary lobule, assoc with scars, ptx
• Bullae: Emphysema with more than 1 cm in
diameter with wall thickness < 1mm
Emphysema Chest X-ray
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Hyperinflation
Flat diaphragms
Widened retrosternal air space
Lung height increased
Small narrow heart
Emphysema lung parenchyma
• Arterial deficiency, increased branching angle
of remaining vessels
• Increased markings / bronchial wall thickening
or superimposed enphysematous walls
Emphysema secondary manifestations
• PA hypertension
HRCT
• Emphysematous holes have no walls, attenuation
values of −950 HU or less on thin-section CT scans
with a 10-mm interval correlate well with
pulmonary function test results and the
pathologic distribution of emphysema, reduced
CT attenuation coefficients
• Bronchial wall thickening
• Hyperinflation
• Expiratory air-trapping
• Vascular pruning
Emphysema-predominant
Radiology Oct 2011
airway-dominant
Figure 1 Axial CT image obtained in a 66- year-old man with COPD and severe airflow obstruction (percentage of predicted FEV1, 40.8%) shows mild
emphysema (relative low-attenuation area with attenuation of −950 HU or lower, 5.8%). Low-attenuation areas representing emphysematous change
(“holes”) are indicated by arrowheads.
RadioGraphics,
http://pubs.rsna.org/doi/abs/10.1148/rg.301095110
Figure 3b (a) Axial CT image obtained in a 72-year-old man with COPD shows multiple low-attenuation areas of emphysema. (b) Axial CT image
obtained with data segmentation shows the same lung field as in a. The total lung parenchymal area (areas with attenuation of −500 to −1024 HU) is
depicted in red, and vascular and other structures are shown in gray. (c) Axial CT image obtained with data segmentation shows the same lung field as
in a and b. Voxels with attenuation of −950 HU or lower are depicted in red, and those with attenuation of −500 to −949 HU are depicted in black.
(Vascular and other nonparenchymal structures are shown in gray.) To quantify the extent of emphysema, the percentage of the total lung area
occupied by voxels with attenuation of −950 HU or lower (ie, the relative low-attenuation area) can be calculated from these segmented CT image data.
RadioGraphics,
http://pubs.rsna.org/doi/abs/10.1148/rg.301095110
Figure 3c (a) Axial CT image obtained in a 72-year-old man with COPD shows multiple low-attenuation areas of emphysema. (b) Axial CT image
obtained with data segmentation shows the same lung field as in a. The total lung parenchymal area (areas with attenuation of −500 to −1024 HU) is
depicted in red, and vascular and other structures are shown in gray. (c) Axial CT image obtained with data segmentation shows the same lung field as
in a and b. Voxels with attenuation of −950 HU or lower are depicted in red, and those with attenuation of −500 to −949 HU are depicted in black.
(Vascular and other nonparenchymal structures are shown in gray.) To quantify the extent of emphysema, the percentage of the total lung area
occupied by voxels with attenuation of −950 HU or lower (ie, the relative low-attenuation area) can be calculated from these segmented CT image data.
RadioGraphics,
http://pubs.rsna.org/doi/abs/10.1148/rg.301095110
Emphysema Pathology
• Abnormal enlargement of airspaces distal to
terminal bronchioles with destruction of
alveolar walls
Figure 4 Coronal CT image obtained in a 62-year-old man with COPD shows upper-lung–predominant emphysema. The relative low-attenuation area
with attenuation of −950 HU or lower (red) is 46.8%, and the percentage of predicted FEV1 is 56.8%.
RadioGraphics,
http://pubs.rsna.org/doi/abs/10.1148/rg.301095110
Figure 5 Coronal CT image obtained in a 72-year-old man shows lower-lung–predominant emphysema. The relative low-attenuation area with
attenuation of −950 HU or lower (red) is 45.8%, and the percentage of predicted FEV1 is 45.6%. The extent of lower-lung–predominant emphysema is
more closely correlated with the result of pulmonary function testing than the extent of upper-lung–predominant emphysema. (In both figures, black
indicates areas with attenuation of −500 to −949 HU and gray indicates vascular and other nonparenchymal structures.)
RadioGraphics,
http://pubs.rsna.org/doi/abs/10.1148/rg.301095110
Figure 8a Volumetric CT-based measurement of airway dimensions. (a) Schema obtained with the region-growing method shows airway
segmentation and selection of a bronchial pathway (black line) for measurement. A curved multiplanar reformatted image is reconstructed along
the selected pathway, and a short-axis image is reconstructed in a plane exactly perpendicular to the long axis of the airway. The red dot indicates the
location of the short-axis image in b. (b) Short-axis image with overlaid diagram shows the radii (red and green lines) used to delimit the inner lumen
and calculate its area. From the point of their intersection, the centroid point, rays (blue lines) are drawn over a 360° radius through the airway wall to
allow calculation of the airway wall thickness by using the full width at half maximum principle.
RadioGraphics,
Figure 8b Volumetric CT-based measurement of airway dimensions. (a) Schema obtained with the region-growing method shows airway segmentation
and selection of a bronchial pathway (black line) for measurement. A curved multiplanar reformatted image is reconstructed along the selected
pathway, and a short-axis image is reconstructed in a plane exactly perpendicular to the long axis of the airway. The red dot indicates the location of
the short-axis image in b. (b) Short-axis image with overlaid diagram shows the radii (red and green lines) used to delimit the inner lumen and calculate
its area. From the point of their intersection, the centroid point, rays (blue lines) are drawn over a 360° radius through the airway wall to allow
calculation of the airway wall thickness by using the full width at half maximum principle.
RadioGraphics,
http://pubs.rsna.org/doi/abs/10.1148/rg.301095110
• Airway-predominant
Rx: medical
Small airway disease
cannot be visualized
directly with current
radiographic techniques,
calculate: the expiratoryinspiratory attenuation
ratio see volumetric CT
based measurement
• Emphysema-predominant
Rx: Sx
• 30% of lung has to be destroyed to alter
pulmonary function
Pulmonary functions
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Increased total and residual volumes
RV(residual volume) >120% predicted
Decreased flow volumes
FEV Forced Expiratory Volume) <80%
predicted
• Decreased diffusion capacity <80% predicted
Alpha 1-Antiprotease deficiency, normally
enzyme blocks proteolytic enzymes
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Panlobular emphysema
Lower lobes
Common Pi ZZ phenotype 1 in 200, gene 14
Normal phenotype: Pi MM; Pi MZ 60% normal
Liver disease in infancy
Premature development of emphysema,
worse with smoking
References
• Regan EA, Hokanson JE, Murphy JR, et al.. Genetic
epidemiology of COPD (COPDGene) study design.
COPD 2010;7(1):32–43. [CrossRef] [Medline]
• SS Kim … D Lynch: Chronic Obstructive Pulmonary
Disease: Lobe-based Visual Assessment of
Volumetric CT by Using Standard Images—
Comparison with Quantitative CT and Pulmonary
Function Test in the COPDGene Study Radiology,
2013, Vol.266: 626-635, 10.1148/radiol.12120385
• S Matsuoka : Quantitative CT Assessment of COPD