What is one of the key methods to reduce patient dose during fluoroscopy?

Using 2.5 mm Al filtration is a key method to reduce patient dose during fluoroscopy because filtration helps to selectively remove low-energy x-rays from the beam. These low-energy photons contribute minimally to image quality but significantly increase the radiation dose to the patient. By using appropriate filtration, the overall radiation exposure can be minimized while maintaining the necessary image quality for diagnostic purposes. This technique effectively enhances the penetration of the x-ray beam, allowing the higher-energy, more diagnostic x-rays to be transmitted through the patient while reducing the patient's exposure to unnecessary radiation.

In comparison, decreasing the source-skin distance or increasing the x-ray tube proximity would generally lead to an increase in radiation dose to the patient, as the intensity of the x-ray beam increases as you get closer to the source. Using higher kVp settings, while it can reduce patient dose by decreasing the number of low-energy photons, it might not be the most efficient method in fluoroscopy where image quality is paramount.