CAMRT Radiography Practice Exam

Window width in CT controls?

1. Density

2. Mid range of densities

3. Resolution

4. Gray scale

The correct answer is: Gray scale

Window width in computed tomography (CT) refers to the range of CT numbers or attenuation values displayed in the final image. It determines how many shades of gray are shown in the image, which directly affects the contrast and visibility of different tissues. A narrow window width results in a limited range of gray levels, which can enhance the visibility of subtle differences in densities, particularly between similar tissues. When considering what window width controls, the primary function is to define the gray scale or the range of gray levels present in the final image. This is essential for radiologists and clinicians to interpret the images accurately, as it allows for a better differentiation of anatomical structures based on their attenuation properties. The concept ties in closely with the idea of window level, which adjusts the mid-point of the grayscale values displayed, allowing for further fine-tuning of image contrast and brightness. By understanding the relationship between window width and gray scale, radiographers can optimize imaging protocols to ensure the best possible diagnostic outcomes.