What areas of an image should be shuttered?

The areas of an image that should be shuttered are typically those that are overly bright or have excessive exposure. Bright white areas can indicate regions of the image that do not contain useful diagnostic information or may lead to confusion in interpreting the image. Shuttering helps to enhance the contrast and quality of the radiographic image by removing these unwanted bright areas, ensuring that the focus remains on the essential anatomical structures being examined.

For instance, if an image includes bright white areas resulting from unexposed film or scattered radiation, it can obscure important details within the anatomy of interest. Shuttering is a technique employed to optimize image quality and prevent unnecessary exposure to those areas outside of the desired field, which could detract from the overall diagnostic value of the image.

In contrast, darker regions or collimator shadows might not require the same level of focus on shutting down, as they may not interfere as significantly with the interpretation of the important anatomy within the collimated area. Instead, the emphasis should be placed on refining the image by eliminating the areas that could mislead or distract from critical diagnostic details.