What Are "Spot Films" in Mammography, and When Are They Done?

— -- Question: What are spot films in mammography and when are they done?

Answer: Many times if you have a mammogram, the radiologists will see something on the mammogram that probably is just normal tissue but he or she can't tell for sure. And you'll be either called back or on the same day be asked to have additional views, we call them. It's really looking at the breast from a different angle or squeezing the breast with a smaller compression paddle that is like spreading the surface of Jello a little bit to try and see the structures inside the breast with a little more detail.

The spot compression is just a small, plastic compression paddle that puts a little more pressure in one area, and using that we can frequently tell that something that looked suspicious on the original mammogram is actually just one shadow on one side of the breast overlapping another shadow from the other side of the breast and making it look significant when it's really just normal breast tissue. You have to realize that a mammogram is a picture of all the structures in the breast from one side to the other superimposed on one another. It's a two-dimensional projection, as we say, of a three-dimensional structure. And so something on one side of the breast can shadow and project its shadow over something on the other side and it looks like a very strange object when in fact it's two normal objects superimposing.

If you were to take your hands, for example, and put one hand up and cast a shadow on the wall it's very easy to tell it's a hand. But if you then cast a shadow of two hands at different angles, when you look at what is on the wall it looks like a very strange shadow. Well, spot compression allows us to spread those structures apart so we can in fact see that we are dealing with normal tissue or, on the other side of the equation, that there is something abnormal there.

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