Digital chest radiography: an update on modern technology, dose containment and control of image quality

Abstract

The introduction of digital radiography not only has revolutionized communication between radiologists and clinicians, but also has improved image quality and allowed for further reduction of patient exposure. However, digital radiography also poses risks, such as unnoticed increases in patient dose and suboptimum image processing that may lead to suppression of diagnostic information. Advanced processing techniques, such as temporal subtraction, dual-energy subtraction and computer-aided detection (CAD) will play an increasing role in the future and are all targeted to decrease the influence of distracting anatomic background structures and to ease the detection of focal and subtle lesions. This review summarizes the most recent technical developments with regard to new detector techniques, options for dose reduction and optimized image processing. It explains the meaning of the exposure indicator or the dose reference level as tools for the radiologist to control the dose. It also provides an overview over the multitude of studies conducted in recent years to evaluate the options of these new developments to realize the principle of ALARA. The focus of the review is hereby on adult applications, the relationship between dose and image quality and the differences between the various detector systems.

The Additional Filter and Ion Chamber Sensor Combination for Reducing Patient Dose in Digital Chest X-ray Projection

“…또한 DR 방식으로 변화하면서 화질의 향상과 더불어 환자 피폭선량 감소 효과를 기대했으나, dose creep현상으로 피폭선량이 증가되는 현상이 발생하고 있다 [13] . 하지만 김 [14] [7] .…”

The Quality/Safety Medical Index: a Standardized Method for Concurrent Optimization of Radiation Dose and Image Quality in Medical Imaging

“…When exposure parameters are chosen manually (e.g., pediatric, intensive care unit patients), technologists tend to favor overexposure because underexposure will lead to radiologist complaints of poor image quality. The resulting dose creep leads to a gradual increase in exposure parameters over time, which can have an important clinical effect when multiple follow-up exams are performed or when patients are particularly radiosensitive [9].…”

“…This well-established mandate calls for radiology providers to achieve high levels of image quality while maintaining low and medically acceptable radiation dose. In the past decade, a shift has taken place from the principle of "image quality as good as possible" to "image quality as good as needed" [9]. This has in effect modified the traditional tenets of ALARA by placing a greater emphasis on radiation dose (i.e., safety) and less emphasis on image quality, as long as image quality is adequate to enable an accurate diagnosis [10,11].…”

Creating Accountability in Image Quality Analysis. Part 2: Medical Imaging Accreditation

“…Technical image quality variables such as noise and exposure are directly impacted by radiation dose and if analyzed in isolation could actually encourage imaging providers to opt for higher radiation dose protocols to maximize technical quality measures. Relevant examples include "dose creep" for digital radiography and full-dose CT, which sacrifice radiation safety for improved technical image quality [8,9]. From a practical standpoint, medical imaging providers utilizing aggressive radiation dose reduction strategies should be encouraged to do so, while taking into account the precarious balance between radiation safety and technical image quality.…”