Infographics / Fluoroscopy

Pulsed fluoroscopy timing and grid-switched output

Timelines comparing continuous fluoroscopy, where the x-ray beam is on throughout, with pulsed fluoroscopy at 30, 15 and 7.5 pulses per second shown over the same time window. Each beam-on pulse stays the same short width in every mode. Fewer pulses per second means proportionally lower patient dose rate, while the short pulse width limits motion blur.

Pulsed fluoroscopy: beam-on timeline and patient dose Timelines comparing continuous fluoroscopy, where the x-ray beam is on throughout, with pulsed fluoroscopy at 30, 15 and 7.5 pulses per second shown over the same time window. Each beam-on pulse stays the same short width in every mode. Fewer pulses per second means proportionally lower patient dose rate, while the short pulse width limits motion blur. Pulsed fluoroscopy: beam-on timeline and patient dose beam on (x-rays delivered) beam off beam-on windows (same time window) patient dose Continuous beam always on highest dose 30 pulses s⁻¹ looks continuous dose rate 1× 15 pulses s⁻¹ motion more stepped ≈ ½× dose 7.5 pulses s⁻¹ most stepped ≈ ¼× dose time Every pulse stays short (2–20 ms), so each frame freezes motion: blur is set by pulse width, not pulse rate. Average dose rate ≈ dose per pulse × pulse rate, so halving the pulse rate roughly halves patient dose. Lower pulse rate saves dose but portrays motion more stepped; ~30 pulses s⁻¹ looks continuous.
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