As the field of view decreases, what happens to the entrance skin exposure (ESE)?

When the field of view decreases in fluoroscopy, the entrance skin exposure (ESE) actually increases. This phenomenon can be explained by the principles of radiation dose distribution in the imaging field.

As the field of view is reduced, the same amount of radiation is directed onto a smaller area. This concentration of exposure results in a higher dose per unit area, leading to an increase in entrance skin exposure. In practical terms, when radiologists or technicians select a smaller field of view, more of the incident radiation is focused on the region being examined, which enhances the imaging quality but also raises the ESE for that area.

This relationship highlights the importance of optimizing fluoroscopy settings. While a decreased field of view can improve image clarity, it is crucial to balance this with the effects on patient dose. Awareness of these dynamics helps practitioners make informed decisions about exposure settings during fluoroscopic procedures, ultimately ensuring patient safety and effective imaging outcomes.