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2004 AAPM Summer School Home

Scientific Program Schedule
Day 4, Sunday, August 1, 2004

Radiographic and Fluoroscopic System Testing and Hardcopy Devices

This final session provides some integration and summarization of themes covered in this course, by describing techniques for overall QA and performance evaluation of digital radiographic and fluoroscopic systems and hardcopy output (still the final product for many imaging systems).

Time Topic & Faculty Objectives
8:00am-8:10am LAC Issues and Announcements  
8:10am-9:10am

Exposure Indicators and AEC Performance Testing with DR and CR

Lee Goldman

Powerpoint Presentation
(4.3 MB)

In film/screen radiography, optical density of resulting films, if used in conjunction with sensitometry-based quality control programs, provides a built-in, generic mechanism for maintaining stable technique factors and consistent image quality--improperly exposed films are recognizably non-diagnostic and thus (hopefully) repeated. Automatic exposure control (AEC) systems are even more important with CR and DR as a tool to avoid underexposed (noisy) or overexposed (excessive radiation) images and exposure creep. In lieu of optical density, digital systems often provide some form of post-read “exposure” or “speed” indication based on radiation reaching the receptor: the Fuji S-number, Agfa LGM number, etc. This lecture discusses the meaning of these speed indicators, how they may be used to evaluate proper AEC performance, and how they may be used maintain proper and stable manual technique factors to assure good image quality and acceptable patient dose.

9:10am-10:10am

Hardcopy Technology, Specifications, Performance Evaluation and QC

Although softcopy viewing of R/F images is expanding, much filming of digital images still occurs for viewing in areas where PACS is unavailable or inaccessible. The goal of this lecture is to provide an overview of the various hardcopy print technologies (both wet and dry), their advantages and disadvantages, and associated performance specifications. Emphasis should be placed on clinically relevant specifications ( printed bit depth, printable graylevels, size of borders, etc). Recommendations for performance testing and ongoing QC activities should be discussed as well. Note that this lecture should not dwell on DICOM print issues, but may if necessary supplement those issues discussed on the PACS and DICOM talk given earlier in the program.

10:00am-10:30am BREAK
10:30am-11:45am

Inspecting Radiographic and Fluoroscopic Systems

Lee Goldman

Powerpoint Presentation
(8.5 MB)

Although previous lectures discussed many aspects of R&F performance evaluation, this lecture would “tie it all together” and overview a complete physics inspection of a (digital) radiographic or R/F system. Traditionally, physics tests tended to measure component-level parameters appropriate for comparison to specific component-level criteria: for example, indicated focal spot size, kVp accuracy and reproducibility, linearity, etc. This lecture should also include recommendations for system levels tests: i.e., designed to evaluate overall performance, such as limiting spatial resolution, image contrast, system speed and patient exposure under specific conditions, much like those performed as part of MQSA tests. It may include material associated with the ACR's Barium Enema accreditation program, as well as other recommendations elsewhere in this program.