CAMRT Radiography Practice Exam

How should oral contrast for CT be mixed for optimal effectiveness?

1. Contrast media is not necessary

2. More concentrated than for general examinations

3. Less concentrated than for general examinations

4. The same for general diagnostic examinations

The correct answer is: Less concentrated than for general examinations

For optimal effectiveness in CT imaging, oral contrast should be less concentrated than what is typically used for general examinations. This is because a less concentrated solution optimizes the visualization of the gastrointestinal tract without causing excessive opacity, which can obscure the anatomy or pathology being evaluated. When administering oral contrast, the goal is to enhance the differentiation of the bowel from surrounding structures and to ensure that the contrast agent adequately coats the intestinal walls. If the concentration is too high, it can lead to artifacts or unwanted highlights that may complicate the interpretation of the images. Therefore, a well-balanced concentration, which is generally less concentrated than that used for other types of diagnostic imaging, allows for clearer and more accurate visualizations during CT scans. In essence, using a less concentrated oral contrast facilitates optimal diagnostic clarity while still effectively opacifying the desired areas for examination.