What leads to foreshortening of a radiographic image?

Foreshortening of a radiographic image occurs primarily due to angling the anatomical part being imaged. When a body part is angled away from the film or detector, it can result in the appearance of that part being compressed, thus shortening it on the image. This is mainly a geometrical distortion resulting from the divergence of rays from the source, which alters the perceived length of the anatomical structure relative to its true length.

In practice, when radiographers angle an anatomical part rather than the X-ray beam or the receptor, they inadvertently change the shape of the structure as it projects onto the film. This can lead to inaccurate representations of sizes and dimensions, which is critical for diagnosis and treatment planning. Understanding this concept is essential for producing high-quality radiographs that accurately represent anatomical structures.