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Parenchymal asymmetry left breast

Case contributed by Dr Garth Kruger


Routine screening study left breast

Patient Data

Age: Adult
Gender: Female

The routine MLO view shows a parenchymal asymmetry deep in the left breast. It is not visible on the CC view so it is likely a summation shadow.

Mammography is part science, part art . Management of an abnormality is part of the practice of breast imaging, so simple "pattern recognition" is not enough to make a good breast imager. Additional mammographic images are part of the diagnostic workup. The mostly used of these images are the "rolled" craniocaudal (CC) view and straight lateral view (SL).


An immediate repeat MLO view shows the shadow is gone. Same breast, same day about 30 minutes apart.

Case Discussion

Rolled CC and SL views are very useful in workup of summation shadows. The degree of difference between the original image and the repeat image does not have to be much either; sometimes even a slight difference in compression will show the summation shadow disappears. In the cas eabove note the change in postion by the profile of the nipple; the second view is technically superior to the first.

In every day practcie, the rolled CC and SL views are more useful than mag views  with asymmetry of the parenchyma. I reserve mag views for calcifications; they take time and extra effort in pratice while the rolled CC and SL views are quick and easy. Amagnified view of a blob rarely gives added sueful information.

If the asymmetry is not present on the other view of the same breast, you are likely dealing with a parenchymal asymmetry.  Always look for the "lesion" on the other view before you do anything else. The converse is true as well; if the lesion is on the other view, its likley real. Then full workup including ultrasound should be done.

Do not be tempted to skip ultrasound; it adds value.

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Case information

rID: 21405
Published: 20th Jan 2013
Last edited: 14th Aug 2019
System: Breast
Inclusion in quiz mode: Excluded

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