Medical physics 3.0 versus 1.0: A case study in digital radiography quality control.

Purpose: The study illustrates how a renewed approach to medical physics, Medical Physics 3.0 (MP3.0), can identify performance decrement of digital radiography (DR) systems when conventional Medical Physics 1.

Automated quality control assessment of clinical chest images.

Purpose: The purpose of this study was to determine whether a proposed suite of objective image quality metrics for digital chest radiographs is useful for monitoring image quality in a clinical setting unique from the one where the metrics were developed.

Methods: Seventeen gridless AP chest radiographs from a GE Optima portable digital radiography (DR) unit ("sub-standard" images; Group 2) and 17 digital PA chest radiographs ("standard-of-care" images; Group 1) and 15 gridless (non-routine) PA chest radiographs (images with a gross technical error; Group 3) from a Discovery DR unit were chosen for analysis. Group 2 images were acquired with a lower kVp (100 vs 125) and shorter source-to-image distance (127 cm vs 183 cm) and were expected to have lower quality than Group 1 images.

Evaluation of cassette-based digital radiography detectors using standardized image quality metrics: AAPM TG-150 Draft Image Detector Tests.

The purpose of this study was to evaluate several of the standardized image quality metrics proposed by the American Association of Physics in Medicine (AAPM) Task Group 150. The task group suggested region-of-interest (ROI)-based techniques to measure nonuniformity, minimum signal-to-noise ratio (SNR), number of anomalous pixels, and modulation transfer function (MTF). This study evaluated the effects of ROI size and layout on the image metrics by using four different ROI sets, assessed result uncertainty by repeating measurements, and compared results with two commercially available quality control tools, namely the Carestream DIRECTVIEW Total Quality Tool (TQT) and the GE Healthcare Quality Assurance Process (QAP).

Essentials and guidelines for clinical medical physics residency training programs: executive summary of AAPM Report Number 249.

There is a clear need for established standards for medical physics residency training. The complexity of techniques in imaging, nuclear medicine, and radiation oncology continues to increase with each passing year. It is therefore imperative that training requirements and competencies are routinely reviewed and updated to reflect the changing environment in hospitals and clinics across the country.

Evaluation of a commercial cardiac motion phantom for dual-energy chest radiography.

Misregistration due to cardiac motion causes artifacts in two-exposure dual-energy subtraction images, in both the soft-tissue-only image and the bone-only image. Two previous investigations have attempted to avoid misregistration artifacts by using cardiac gating of the first and second exposures. The severity of misregistration was affected by the heart rate, the time interval between the low- and high-energy exposures, the total duration of the two exposures, and the phase of the cardiac cycle at the start of the exposure sequence.

The long-term impact of a performance improvement continuing medical education intervention on osteoporosis screening.

Introduction: The purpose of this study is to determine whether a performance improvement continuing medical education (PI CME) initiative that utilizes quality improvement (QI) principles is effective in producing sustainable change in practice to improve the screening of patients at risk for osteoporosis.

Methodology: A health care center participated in a PI CME program designed to increase appropriate osteoporosis screening. There were eight 1-hour educational sessions for this activity over a 9-month period.

Gain and offset calibration reduces variation in exposure-dependent SNR among systems with identical digital flat-panel detectors.

Purpose: The conditions under which vendor performance criteria for digital radiography systems are obtained do not adequately simulate the conditions of actual clinical imaging with respect to radiographic technique factors, scatter production, and scatter control. Therefore, the relationship between performance under ideal conditions and performance in clinical practice remains unclear. Using data from a large complement of systems in clinical use, the authors sought to develop a method to establish expected performance criteria for digital flat-panel radiography systems with respect to signal-to-noise ratio (SNR) versus detector exposure under clinical conditions for thoracic imaging.

One year's results from a server-based system for performing reject analysis and exposure analysis in computed radiography.

Rejected images represent both unnecessary radiation exposure to patients and inefficiency in the imaging operation. Rejected images are inherent to projection radiography, where patient positioning and alignment are integral components of image quality. Patient motion and artifacts unique to digital image receptor technology can result in rejected images also.

An exposure indicator for digital radiography: AAPM Task Group 116 (executive summary).

Digital radiographic imaging systems, such as those using photostimulable storage phosphor, amorphous selenium, amorphous silicon, CCD, and MOSFET technology, can produce adequate image quality over a much broader range of exposure levels than that of screen/film imaging systems. In screen/film imaging, the final image brightness and contrast are indicative of over- and underexposure. In digital imaging, brightness and contrast are often determined entirely by digital postprocessing of the acquired image data.

Optimizing digital radiography of children.

Pediatric projection imaging differs from imaging of the adult patient. Children are smaller, more radiosensitive, and less compliant than their adult counterparts. Their characteristics affect the way projection imaging is practiced and how dose is optimized.

Consequences of modern anthropometric dimensions for radiographic techniques and patient radiation exposures.

Radiographic techniques are devised on the basis of anatomic dimensions. Inaccurate dimensions can cause radiographs to be exposed inappropriately and patient radiation exposures to be calculated incorrectly. The source of anatomic dimensions in common usage dates back to 1948.

Measurement of CT radiation profile width using CR imaging plates.

This paper describes the procedure for using a Fuji computed radiography (CR) imaging plate (IP) for the measurement of computed tomography (CT) radiation profiles. Two sources of saturation in the data from the IP, signal and quantization, were characterized to establish appropriate exposure and processing conditions for accurate measurements. The IP generated similar profiles compared to those obtained from digitized ready-pack films, except at the profile edges, where the exposure level is low.

The continued evolution of the credit system.

In its ongoing support of continuous physician professional development, the American Medical Association (AMA) for use in the AMA Physician's Recognition Award has adopted 2 new learning platforms: Performance Improvement (PI) and Internet Point of Care (PoC). This article highlights the process that led to their adoption and places these new forms of continuing and physician professional development in the framework of existing continuing medical education (CME). The article calls for new research that revisits existing data on physician learning and prepares to incorporate provider experience with "practice situated" forms of CME.

Assessment of display performance for medical imaging systems: executive summary of AAPM TG18 report.

Digital imaging provides an effective means to electronically acquire, archive, distribute, and view medical images. Medical imaging display stations are an integral part of these operations. Therefore, it is vitally important to assure that electronic display devices do not compromise image quality and ultimately patient care.

A new metric for continuing medical education credit.

The two major continuing medical education (CME) credit systems for allopathic physicians in the United States are administered by the American Medical Association (AMA) and the American Academy of Family Physicians (AAFP). This article explores the history of AMA and AAFP CME credit and its value to physicians and the patients they serve. Historically, CME credit has been awarded as hours for participation, but this approach is inadequate as a measure of CME and its impact on improving physician practice.

Implementing the DICOM Grayscale Standard Display Function for mixed hard- and soft-copy operations.

The aim of this work was to implement the DICOM Grayscale Standard Display Function (GSDF) at all stages of image presentation for computed radiography (CR) and direct digital radiography (DR) modalities. Cathode-ray tubes (CRT) were calibrated according to vendor procedures. Printer look-up-tables (LUT) were measured.