Radiologic Technologist Practice Exam

Which type of compensating filter is most suitable for an AP or AP axial projection of the foot?

1. Boomerang

2. Wedge

3. Trough

4. Bilateral wedge

The correct answer is: Wedge

The wedge compensating filter is most suitable for an AP or AP axial projection of the foot due to its effective design that allows for the even distribution of X-ray exposure across varying thicknesses of anatomy. The foot presents a challenge in terms of varying tissue thickness; the heel is thicker than the toes. A wedge filter is designed to be thicker at one end and taper towards the other, which compensates for this thickness difference. By placing the thicker side under the heel, it helps reduce the radiation intensity in that area, while allowing more X-rays to penetrate through the toes. This results in better image quality by ensuring that the radiograph displays uniform density across the entire foot, thus enhancing the visibility of anatomical structures. Other types of filters, such as the boomerang or trough filters, may not provide the same level of appropriateness for this specific projection. A boomerang filter is more useful for imaging anatomical areas with significant curvature, while a trough filter is typically employed for bilateral structures where specific areas need to be compensated for increased thickness but may not effectively address the specific needs of an AP foot projection. The bilateral wedge is also less commonly used for this specific application as it is designed for different imaging scenarios. Therefore, the wedge filter is