1. RAD 150 Fluoroscopy
Fluoro’s primary function is to enable one to view the patient in “real time” with dynamic (motion)

2. Fluoro was first invented by Thomas Edison in 1896
Utilized a conventional x-ray unit with a fluorescent screen that would convert the x-rays exiting the patient to low level light the radiologist could view

3. Image Intensified Fluoro

4. II Fluoro
Increased image brightness with II over direct fluoro is the biggest advantage of II
Usually controlled by “automatic brightness control” (ABC) that the radiologist can preset and control

5. Eyes use rods and cones
Photopic vision – daylight vision uses the CONES
Scotopic vision - night time vision and uses the RODS

6. Fluoro Techniques
Fluoro usually is operated at 5 mAs and uses highest optimum kVp
Protective Fluoro measures
Bucky slot cover
Lead curtain
5 min back up timer
Lead gloves and aprons (secondary barriers!)
Distance

7. Image intensifier tube
Dang it – I couldn’t find a diagram to import here!!!!!!!
Input phosphor
Photocathode (photo emission)
Evacuated glass envelope
Electrostatic focusing lens (neg. charged!!!!)
Anode
Output phosphor

9. Gain Minification gain – ratio of input to output sizes
Flux gain – ratio of # of input PHOTONS to output LIGHT PHOTONS
Brightness gain (total brightness gain)= minification gain X flux gain

10. Fluoro Magnification
Most fluoro II units have dual input phosphor sizes (9” and 6” [27/17 cm]
Some have TRI – input (trifield tubes 27/17/12 cm)
The crossover of the electron stream distance from the output phosphor determines the amount of magnification
Mag mode = better spatial resolution, better contrast resolution, HIGHER pt. dose

11. TV Monitoring Must “couple” the output phosphor to a TV camera tube
Vidicon tube is MOST frequently used – plumbicon also can be used
Fiber optics and beam splitters are used to help direct the digitized image to the various destinations (TV monitor, photo spot film camera, VCR/CD recorder, cine camera)