What is the formula for magnification?

The formula for magnification in fluoroscopy is given by the ratio of the source-to-image distance (SID) to the source-to-object distance (SOD). This relationship arises from the principles of similar triangles, which can be observed when considering the setup in fluoroscopy.

When the image is projected, the SID represents the distance from the X-ray tube to the image receptor, while the SOD refers to the distance from the X-ray tube to the object being examined (like a patient's body). The greater the distance from the tube to the image receptor compared to the distance from the tube to the object, the larger the magnification of the object appears on the image receptor.

Therefore, using the formula mag = SID/SOD allows us to quantitatively determine how much larger an object appears compared to its actual size, enabling radiologic technologists to accurately assess and document findings during procedures. It is a crucial concept to ensure the proper evaluation of images in fluoroscopic applications.