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Grid conversion factors were established for using grids with varying ratios for film-screen systems. Evidence from the physics community suggests that the relationship between grid conversion factors and exposure to the receptor does not apply with different types of digital imaging receptors.To evaluate the relationship among analog grid conversion factors when using various grid ratios with a photostimulable phosphor plate (PSP) receptor system.Three experiments were conducted using a range of grid ratios (6:1, 8:1, 12:1) to assess the effect of conversion factors on exposure indicators with a computed radiography PSP receptor.When using the analog grid conversion factors established for varying grid ratios with a PSP receptor and constant peak kilovoltage (kVp), the plate was overexposed with an exposure indicator outside the acceptable limits.The discussion of antiscatter grids in radiologic technologist literature should remain in the context of receptor type and digital imaging system being used so that technologists can make appropriate decisions about the use of grids while minimizing patient radiation dose. Calibrated grid conversions based on the digital systems in use and the radiologist's image quality preference could be created within radiology departments.

Medical imaging has undergone dramatic changes and technological breakthroughs since the introduction of digital radiography. This article presents information on the development of digital radiography and types of digital radiography systems. Aspects of image quality and radiation exposure control are highlighted as well. In addition, the article includes related workplace changes and medicolegal considerations in the digital radiography environment.

Traditionally, conventional radiography has been used to identify the structural damage associated with juvenile idiopathic arthritis (JIA). As other modalities have developed, however, the practice of assessing and monitoring JIA with radiographs has been questioned.The purpose of this study was to examine the current best practices for imaging JIA and to assess various imaging modalities.A literature review was conducted to examine to what extent radiography, magnetic resonance (MR) imaging, ultrasonography and computed tomography (CT) aid in diagnosing and managing JIA, and the benefits and limitations of each modality.No single modality meets every imaging need at this time, but methods for detecting JIA are dramatically improving. Diagnostic radiography, MR imaging, ultrasonography and CT all play an important role in diagnosing or monitoring JIA.

Dry-processed radiographic films should be stored in a temperature-controlled environment away from direct light to prevent image deterioration. However, films occasionally are subjected to other conditions, such as when they are left inadvertently on viewing boxes or removed from the radiology department.To assess the effects of heat and light on optical density in radiographic films produced with dry laser imagers.Step-wedge images generated by a dry laser imaging system were placed on an illuminated viewing box, inside the trunk of a car and in direct sunlight on a hot day for varying lengths of time. Changes in optical density (OD) then were measured with a densitometer. Changes of more than 2 standard deviations from the original OD were attributed to the effects of light and heat.The films left on a viewing box and inside a car's trunk did not show significant changes in OD. However, films subjected to direct sunlight for 30 minutes or more at an average temperature of 40 degrees C (104 degrees F) showed significant changes in OD in the straight-line portion of the Hurter and Driffield curve.Dry-processed films can degrade when exposed to temperatures higher than 35 degrees C (95 degrees F) and should be stored properly to avoid affecting their diagnostic quality.

Digital image processing is now commonplace in radiology, nuclear medicine and sonography. This article outlines underlying principles and concepts of digital image processing. After completing this article, readers should be able to: List the limitations of film-based imaging. Identify major components of a digital imaging system. Describe the history and application areas of digital image processing. Discuss image representation and the fundamentals of digital image processing. Outline digital image processing techniques and processing operations used in selected imaging modalities. Explain the basic concepts and visualization tools used in 3-D and virtual reality imaging. Recognize medical imaging informatics as a new area of specialization for radiologic technologists.

The purpose of this investigation was to report the life span of Escherichia coli, Enterococcus faecalis and Staphylococcus aureus on 3 types of radiographic imaging receptors currently used in diagnostic imaging departments in the United States. Kodak 400 speed, Dupont 400 speed and Fuji computed radiography cassettes were inoculated with the 3 bacteria, then placed in an incubation cabinet and cultured for a period of 2 weeks. All 3 cassettes revealed confluent growth with no noticeable reduction in bacterial numbers for the entire test period. This study verifies that common potentially pathogenic bacteria can survive for prolonged periods on radiographic imaging cassettes. Therefore, effective cleaning regimens are of fundamental importance in controlling and preventing potential nosocomial transmission in the diagnostic imaging department.

In this study, entrance skin doses for AP pelvis and lateral lumbar spine examinations were measured with single-phase, three-phase and medium frequency x-ray generators. Results showed that for equal tube voltage (kVp) exposure to achieve similar film density, the ESD was significantly higher with the single-phase generator than the other two generators. Further research showed that by increasing kVp, the single-phase generator could achieve the lower ESD values obtained with the three-phase and medium frequency generators while maintaining similar film density and contrast.

Improper x-ray film processing is a problem for both providers and consumers of diagnostic radiology services. This article reports the findings of a study that monitored film processing practices at 297 facilities. The study showed film processing quality is inconsistent and that definitive standards need to be established for the industry.

The Wisconsin Test Cassette, long the standard for non-invasive evaluation of kilovoltage, isn't known for its simplicity or convenience during use. The author presents a computer-generated worksheet that simplifies kilovoltage accuracy checks and customizes cassettes according to calibration curve data.

As funding for high technology equipment decreases, diagnostic imaging will experience a notable renewal. Radiographers must improve the image quality and reduce the integral dose patients receive. By increasing the focal film distance from 40 inches to 50 inches, the authors have significantly increased the image quality and reduced the integral and cumulative dose of radiation by 12.5 percent.