Mammography views

There are numerous mammography views that can broadly be split into two groups

1. standard views 
2. supplementary views - additional information or problem solving

Standard views

Standard views are bilateral craniocaudal (CC) and mediolateral oblique (MLO) views, which comprise routine screening mammography. The views are usually used for all routine screening clients. That is, unless there is a contraindication, screening mammograms consist of these 4 views.

Not all 4 views are always performed in all mammogram studies.  For instance, in clients under 40 only 2 MLO views may be done to limit radiation exposure, depending on local policy and the discretion of the radiologist.

In cases of recent surgery limited imaging may also be appropriate. Where a patient has painful breast pathology or large lesions or an abscess, imaging should be tailored to specific cases and is usually only done after consultation with the radiologist. Common sense should prevail.

MLO versus ML 

The reason is that a mammogram is a two dimensional representation of a 3 dimensional structure; by the same token a map is not an accurate representation of the earth's actual geography. The ML view loses significant tissue volume in the upper outer quadrant of the breast where statistically the most breast cancers are found. By doing an MLO view you get extra tissue without extra exposure. The downside of the MLO view is it is not 90 degrees to the cc view so localisation of a lesion requires some thought. The two views are not orthogonal.

• craniocaudal view (CC view)
• mediolateral oblique view (MLO view)

Additional (supplementary) views

These views are used in diagnostic breast workups in addition to the standard views.

• true lateral view - 90º view 
  • mediolateral view - ML view
  • lateromedial view - LM view
• lateromedial oblique view - LMO view
• late mediolateral view - late ML view
• step oblique views
• spot view - spot compression view
• double spot compression view
• magnification view(s)
• exaggerated craniocaudal views - exaggerated CC views
  • XCCL view
  • XCCM view
• axillary view - axillary tail view
• cleavage view - valley view
• tangential views
• caudocranial view - reversed CC view - 180° CC view
• bullseye CC view
• rolled CC view
• elevated craniocaudal projection
• caudal cranial projection
• 20° oblique projection 
• inferomedial superolateral oblique projection
• Eklund technique

When to use which view 

As a general rule, parenchymal asymmetries are worked up with straight lateral (SL) and rolled CC (rolled) views. Calcifications are worked up with magnification views (mag views). The degree of roll does not have to be very significant in most cases. All you are trying to achieve with SL and rolled views is to separate summation shadows from each other. Very often a summation shadow seen on an MLO view will disappear if the very same view is immediately performed.

In practice, additional views are always followed by ultrasound if there is a positive finding. The converse is true as well. When doing diagnostic work up on a breast do not be tempted to skip the additional views or the ultrasound. They each add value.