Fluoroscopy Static Image Recording Systems Based on: Principles of Radiographic Imaging, 3rd Ed. By: R. Carlton & A. Adler Radiologic Science for Technologists, 8th Ed. By: S. Bushong Syllabus on Fluoroscopy Radiation Protection, 6th Rev. By: Radiologic Health Branch – Certification Unit PPT created by: Jed Miles, BSRS, RT(R), CRT-CA

Static Recording Systems Static images are necessary when a permanent record of the fluoroscopic examination is required Spot filming can be performed in a manner that functions as a single image or a series of images simulating a dynamic recording (serial spot films) Spot filming is accomplished by: Cassettes (film/screen & imaging plate) 100 or 105 mm chip film (cut film, sheet film) 70 or 100 mm roll film (long roll of film)

Cassette Recording Cassette spot filming uses standard radiographic cassettes Cassette spot filming utilizes the remnant (pre-intensified) exiting radiation from the patient Standard sizes include: 9” x 9” (24 x 24 cm) 8” x 10” (18 x 24 cm) 10” x 12” (24 x 30 cm) Other spot film changers will take 11”x14” and 14”x17

Cassette Recording – How it Works Cassette is stored in a lead lined compartment in the fluoro carriage Controls on fluoro carriage initiate mechanism for spot film exposure Cassette is transported to intercept the primary transmitted x-ray beam X-ray tube current is boosted to 100 - 1,200 mA Carriage controls permit selection of different areas of cassette to be exposed 1on1, 2on1, 3on1, 4on1 etc Collimator shutters AND spot film mask shutters automatically mask to desired area of exposure Cassette is auto centered to proper area to be exp

Cassette Recording – How it Works After the exposure in initiated, the AEC terminates the exposure at the set density Cassette is returned to the ‘park’ position in storage compartment Cassette spot filming causes the single highest dose rate of all fluoro recording mediums May require up to 300µR per exposure at the cassette Translates into over 30 mR entrance skin exposure (ESE) Estimated that each spot film may be equal to more than one minute of fluoroscopic time There is a significant tendency to over document negative findings in the U.S. due to malpractice litigations

Photo Spot Recording (roll, chip, cut or sheet film) Photospot or spot film cameras photograph the image on the output phosphor of the image intensifier Typically uses a much higher mA with short exposure time to acquire an image as compared to simple fluoroscopy 20 – 50 times higher dose per frame than fluoro Still a substantial dose reduction compared to cassette spot film (about 50% reduction per image) If serial photospots are taken – dose will increase Photospot camera are close in design to a cine camera Functionally is much slower Use larger film sizes Larger the film format – better the image quality Larger the film format – larger the required dose

Photospot Recording – How it Works Photospot film changers use either a roll or cut film contained in a supply magazine 70 mm and 105 mm roll film Camera can operate up to 12 frames / second Prior to exposure film is positioned in the aperture A shutter is opened and the x-ray system is energized Light from the output phosphor is reflected by a beam splitting mirror toward the film After the exposure, the shutter is closed and the film is advanced to the next position for the process to repeated Film is collected in a receiver magazine for transport and wet chemical processing Like sheet film used in conventional radiography the cut and roll film requires wet chemical processing

105 mm Roll Film Camera TV Camera 70mm camera 70mm camera supply and take-up magazine 70mm camera Light distribution center Image intensifier

105 mm Roll Film Camera Camera removed from light distribution center of image intensifier

105 mm Roll Film Camera Roll film supply magazine removed from photospot camera Roll film removed from supply magazine

UGI Series using 105 mm roll film Images are cut into strips of 4 and laminated together for ease of handling

105 mm Roll film showing UGI and BE Photospot images An optical “Overframe” method was used to project the image onto the film

Chip or Sheet Film Changers Chip film changers use individual sheets of 100 or 105 mm film contained in a magazine Operationally the camera works nearly identical to a roll film changer, with the exception of a mechanical device to handle sheet film An exposed film receiver stores the images prior to wet chemical film processing of individual sheets

Comparison of various image intensification viewing systems California State Syllabus on Fluoroscopy: page 35

California State Syllabus on Fluoroscopy: page 36 Comparison of image recording systems California State Syllabus on Fluoroscopy: page 36

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