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Distance in Fluoroscopy - Video Lesson

Hey, everybody. This lesson discusses common measurements of distance and fluoroscopy. These concepts impact patient dose, image quality, and occupational dose, so they're important to master. Like radiography, fluoroscopy is concerned with both source to image distance, or SID, and object to image distance, or OID. An additional measurement that applies in fluoroscopy is source to skin distance or SSD. Just like the name suggests, SSD is the distance between the X-ray source and patient skin. Remember, the x-ray beam on time is much longer in fluoroscopy, so this is very important to understand. This extended beam on time can result in skin reddening or burning, especially when using smaller SSDs. So the relationship between SSD and patient dose is inversely proportional. Reduced SSD results in an increase in patient dose and increased SSD results in a decrease in patient dose.