CAMRT Radiography Practice Exam

What kVp setting is optimal for achieving high contrast in imaging?

1. High kVp

2. Low kVp

3. Medium kVp

4. Variable kVp

The correct answer is: Low kVp

To achieve high contrast in imaging, a low kVp setting is optimal because it increases the differential absorption of radiation by different tissues. When using low kVp, the range of photon energies is reduced, which means that only lower energy photons penetrate less dense structures, leading to more significant differences in the attenuation of the x-ray beam by various tissues. This results in darker and lighter areas that create a higher contrast image, allowing for better visualization of anatomical details. In contrast, higher kVp settings produce a wider range of photon energies, which allows more uniform penetration through various tissues and often results in images with lower contrast. A medium kVp setting may offer a balance but does not maximize contrast the way a lower setting does. Variable kVp can lead to inconsistent image quality as it depends on the specific situation and could result in varying levels of contrast depending on the chosen settings. Thus, a low kVp is the most effective approach for maximizing image contrast.