Learning objectives
The purposes of this exhibit are to review of mosaic attenuation pattern on chest computed tomography.
To categorize mosaic attenuation pattern,
various etiology and pathophysiology according to imaging characteristics.
To discriminate radiologic features between causes of mosaic attenuation pattern.
Background
Mosaic attenuation (Inhomogeneous lung opacity) is a term of describing computed tomography (CT) imaging pattern.
It is used to describe when inhomogeneous areas of differing lung attenuation are seen.
Definition suggested by Fleischner society is ‘‘Patchwork of regions of differing attenuation seen on CT of the lungs”.
Originally it was called as “mosaic oligemia and perfusion”.
But mosaic attenuation is more inclusive term,
and mosaic oligemia or mosaic perfusion implies ‘pulmonary vascular pathology’.
Normal lung attenuation on chest CT
Not only air but also blood...
Imaging findings OR procedure details
Strategy for differentiation
Below are strategies for differential diagnosis.
Analysis of vascularity in low attenuation area
Perform Expiratory Imaging
Analysis the Pulmonary artery
Analysis the Airways
Analysis the Heart
Find additional clues
When you face to mosaic pattern lung attenuation,
to determine which portion of the lung parenchyma is abnormal is most important point and that is the first step to do.
Analysis of vascularity in the low attenuation area is the first thing to do.
Small airway disease and pulmonary vascular disease shows decreased...
Conclusion
Mosaic attenuation pattern may represent small airway disease,
pulmonary vascular disease and parenchymal disease.
Analysis the number and the size of pulmonary vessels in the area of low attenuation area helps the diagnosis to small airway disease or pulmonary vascular disease.
In small airway disease,
air trapping in expiratory CT,
large airway dilatation of wall thickening in the low attenuation area,
and small centrilobular nodules are important findings.
In pulmonary vascular disease,
dilated pulmonary artery and dilated right heart are clues and additional findings such...
References
Worthy SA,
Muller NL,
Hartman TE,
et al.
Mosaic attenuation pattern on thin-section CT scans of the lung; differentiation among infiltrative lung,
airway,
and vascular disease as a cause.
Radiology 1997; 205:465-470
Arakawa H,
Webb WR,
McCowin M,
et al.
Inhomogeneous lung attenuation at thin-section CT: diagnostic value of expiratory scans: Radiology 1998;206: 89-94
Stern EJ,
Swensen SJ,
Hartman TE,
et al.
CT mosaic pattern of lung attenuation: distinguishing different causes.
AJR am J Roentgenol 1995; 165: 251-158
Primack SL,
Muller NL,
Mayo JR,
et...
Personal Information
Department of Radiology,
Dong-A University Hospital,
Busan,
Korea
* Corresponding author:
Ki-Nam Lee.
M.D.
Ph.D.
Professor,Thoracic Imaging,
Department of Radiology,
Dong-A University College of Medicine,
Republic of Korea
Office: (82/51)240-5367,
Fax: (82/51)253-4931
[email protected]