What effect does the anode heel effect have on the X-ray beam?

The anode heel effect is a phenomenon that occurs in X-ray production, whereby radiation intensity varies across the X-ray beam. Specifically, the intensity of the X-ray photons is greater on the cathode side of the tube compared to the anode side. This occurs due to the geometry of the X-ray tube and the way in which X-rays are emitted; the angle of the anode creates a situation where the path length of the X-rays emitted from the anode side is longer, resulting in more absorption of photons.

This effect leads to an uneven distribution of radiation intensity across the beam. As a result, when imaging certain anatomical structures, practitioners must be aware of this variation to avoid poor image quality, particularly in scenarios where even exposure is critical. The knowledge of the anode heel effect is particularly useful for positioning patients and optimizing image quality, ensuring that the denser parts of anatomy are aligned with the cathode side for improved exposure, while the thinner parts may be aligned closer to the anode side.

The concept of increased focal spot size pertains to the resolution and sharpness of the image and is not directly related to the distribution of the X-ray beam. Hence, the option regarding uniform exposure does not apply, as the heel effect inherently