How can excessively high contrast in a CT image be improved?

When addressing excessively high contrast in a CT image, the most effective approach is to increase the window width (WW). Window width determines the range of Hounsfield units (or CT numbers) displayed in the image. A wider window width allows for a greater range of values to be represented, which effectively reduces contrast by making more shades of grey available in the visual representation. This can help blend extreme brightness or darkness in the areas of the image, creating a more balanced view that aids in better interpretation.

By increasing the window width, you allow softer variations in tissue density to be more visible, resulting in a less harsh and more detailed representation of the structures in the scan. This makes it easier for radiologists to identify and diagnose conditions without being overwhelmed by high contrast areas that can obscure details.

The other options, such as increasing or decreasing the window level, can adjust the brightness of the image but do not significantly address the issue of high contrast by expanding the range of visible data. Decreasing window width would further exaggerate the contrast rather than mitigate it. Therefore, increasing the window width is the most appropriate method for improving excessively high contrast in CT images.