PACS monitors: an evolution of radiologist's viewing techniques

Perspectives and perceptions of urgent and alert values in surgical pathology and cytopathology: A survey of clinical practitioners and pathologists

In previous editorials, Chapman and Otis in 2011 and Layfield in 2014 have summarized much of the work responsible for establishing the concept of critical diagnoses in surgical pathology and cytopathology. Both editorials end with a list of 8 key policy points needed for an effective strategy of handling and communicating critical diagnoses. We have developed and distributed a Web-based survey to elicit clinicians' attitudes regarding many of those key policy points, such as how, when, and to whom critical diagnoses should be reported; we have allowed some level of collaboration with the clinical staff when developing our communication policies as the Association of Directors of Anatomic and Surgical Pathology (ADASP) consensus statement recommends. We have identified important areas of disagreement between pathologists and clinicians regarding what entities should be considered critical and who should be responsible for correlating histologic findings with the larger clinical context. Identifying these discordant points of view and fostering interdepartmental agreement on the best practices in the communication of critical diagnoses is an important patient care and safety issue. Chapman and Otis have also suggested the importance of increased access to accurate patient information and the clinical history, including the level of clinical suspicion of malignancy, and of forming a periodic review and quality assurance process. Here we explore methods of increasing the ability of pathologists and cytopathologists to identify unexpected diagnoses, including optimization of their workstations for better access to the electronic medical record, and we examine the progress of quality assurance methods in surgical pathology and cytopathology since the ADASP consensus statement in 2012.

Radiologist Digital Workspace Use and Preference: a Survey-Based Study

Literature regarding the heterogeneity of and preferences for radiology workstation design-and, in particular, the digital workspace of the radiology workstation-is scant. The purpose of this study was to determine the nature of the digital environments across the specialty and the degree of satisfaction users associated with the particular facets of those environments. A survey was sent to the membership of the Association of University Radiologists in February 2015. The survey comprised 10 questions establishing demographics, current typical workstation setup, perceived satisfaction with that setup, and preferences for potential altered setups. A total of 336 radiologists responded, with a cross-section similar to that described in the 2015 ACR annual workforce survey (1). Although there was a rough split in the number of radiologists using one or two non-diagnostic monitors (46 vs. 51%, respectively), the strong majority (75%) of radiologists use two diagnostic monitors. Users of two non-diagnostic monitors were more likely to keep open the case info (87 vs. 68%) and EMR (84 vs 68%). More senior radiologists tended to find the current setup easy more frequent than younger radiologists, and the latter group was more likely to believe additional monitors would be helpful. Although many radiologists are comfortable with their computing workflows, a significant number indicate dissatisfaction and may be interested in being able to specify the amount of monitor space with which they can work. Additional monitors may promote improved quality in addition to any potential productivity gains.

Work-Related Injuries of Radiologists and Possible Ergonomic Solutions: Recommendations From the ACR Commission on Human Resources

Increasingly, radiologists' workplaces revolve around PACS and digital imaging. Use of these technologies can lead to repetitive strain injuries, many of which can be exacerbated by specific features of a radiology practice environment. Ergonomic approaches, such as proper reading room structure, lighting, temperature, noise, and equipment setup, can help decrease the frequency and severity of repetitive strain injuries and improve radiologist productivity. However, ergonomic approaches are complex, include all aspects of the radiology practice environment, and are best implemented along with proper training of the practicing radiologists. The ergonomic approaches considered most important by members of the ACR Commission on Human Resources are presented in this report, and this information may serve as an aid in departmental planning.

Comprehensive review of the limitations of relative value unit measurements of productivity in academic departments

Measuring radiologist, especially sonologist, productivity has never been of greater interest than now, as radiology has moved from its historical status as a cost center to the largest revenue generator in most institutions. With more local institutional and federal oversight and regulation into the reimbursement and valuation of imaging procedures, including emphasis on outsourcing, overvalued procedures, and bundling, the ability to measure productivity and to draw meaningful conclusions from the data becomes increasingly imperative if we as radiologists and sonologists expect to contribute meaningfully to the process. This article presents a history of the "relative value unit" and discusses the valuation of radiologist/sonologist productivity in this era of ubiquitous high-technology implementation.

Is targeted reconstruction necessary for evaluating contrast-enhanced chest computed tomography using a liquid crystal display monitor?

PURPOSE

The aim of this study was to examine whether 20-cm field-of-view (FOV) targeted reconstruction (TR) on contrast-enhanced (CE) chest computed tomography (CT) might improve the diagnostic value compared with simple zooming (SZ) from whole-thorax FOV images using a 2 million (2M)-pixel liquid crystal display (LCD) monitor.

MATERIALS AND METHODS

We prospectively evaluated 44 patients. SZ images were magnified from a FOV of 26-34 cm (mean 29.7 cm). Parameters were 512 x 512 matrix and 3 mm thickness and interval. Images were reconstructed using a soft-tissue kernel. Three radiologists evaluated contour, spiculation, notch, pleural tag, invasion, and internal characteristics of the lesions using 5-scale scores. We also performed a phantom study to evaluate the spatial resolution of images.

RESULTS

The diagnostic value of the TR images was similar to that of the SZ images, with the findings identified in 88%-100% of the cases. Artifacts from high-density structures deteriorated the image quality in six (14%), and the SZ images were judged to be preferable in five of them. In the phantom study, there was little difference in spatial resolution between the two images.

CONCLUSION

The SZ images from whole-thorax FOV on CE chest CT were similar in quality to TR images using a 2M-pixel LCD monitor.

User questionnaire to evaluate the radiological workspace

Over the past few years, an increase in digitalization of radiology departments can be seen, which has a large impact on the work of the radiologists. This impact is not only demonstrated by the increased use of digital images but also by changing demands on the whole reading environment. In this study, we evaluated the satisfaction of our radiologists with our digital Picture Archival and Communication System environment and their workspace. This evaluation was performed by distribution of a questionnaire consisting of a score sheet and some open questions to all radiologists and residents. Out of 25 questionnaires, 12 were adequately answered and returned. Results clearly showed that most problems were present in the area of reading room design and layout and comfort and ergonomics. Based on the results from this study, adaptations were made and the results were also used in the planning of the redesign of the entire department of radiology.

Design and Ergonomic Considerations for the Filmless Environment

Planning and executing the redesign of a traditional institutional radiology reading room to conform to the radically different requirements of digital imaging are reviewed, with examples drawn from the authors' experience and from the growing body of literature on this subject. Included are best-practice recommendations and real-life examples on initial design and planning, stakeholder involvement, identifying and hiring consultants, architectural planning, the designation of a radiology point person, rethinking room and workstation design, the selection of ergonomic furniture and fittings, identifying optimal environmental elements, fine tuning and lessons learned, and going digital.

Small-Bowel Obstruction in a Phantom Model of ex Vivo Porcine Intestine: Comparison of PACS Stack and Tile Modes for CT Interpretation

PURPOSE

To compare computed tomographic (CT) image interpretation with picture archiving and communication systems (PACS) stack and tile modes for speed and accuracy of transition zone localization in small-bowel obstruction by using ex vivo porcine specimens.

MATERIALS AND METHODS

Twenty-five small-bowel obstruction phantom models made of ex vivo porcine intestines from a slaughterhouse were imaged at CT. One was used for observer training, and 24 were used for experimentation. At 20-cm intervals throughout the intestines, metallic markers were placed in the mesenteries immediately adjacent to bowel. One obstruction was made in each intestine, midway between markers, by ligating intestine with a 3-0 silk suture to simulate mechanical small-bowel obstruction. The lumen proximal to the ligation site was distended with air and a soybean oil-iodized oil mixture until at least two-thirds of the proximal intestine exceeded 2.0 cm in transverse diameter. Dilated segments were 310-550 cm in length. Soybean oil and a mixture of soybean and iodized oil were used to simulate differences in attenuation among bowel wall, intraluminal fluid, and extraluminal abdominal fat. Four experienced abdominal radiologists independently determined the transition zone by using stack mode (cine viewing of stacked images) and, at least 2 weeks later, tile mode (side-by-side image display). Accuracy and degree of error in counting markers were evaluated, and speed of interpretation was recorded. Statistical analysis was performed with the McNemar and Wilcoxon signed rank tests.

RESULTS

For all observers, accuracy of transition zone localization tended to be better with stack mode (63%-83% [15-20 phantoms]) than with tile mode (50%-63% [12-15 phantoms]), but the differences were not significant. For each observer, mean counting error was lower in stack mode (range, 0.96-2.48) than in tile mode (range, 1.74-3.22), with significance for three observers (P < .01, P < .01, and P = .04). Interpretation was significantly faster with stack mode by a factor of two to three for all observers (P < .01).

CONCLUSION

Stack mode evaluation for identification of the transition zone in obstructed small bowel is faster than evaluation with tile mode. Accuracy is not significantly different between modes, although there is a tendency toward better results with stack mode.

On-axis and off-axis viewing of images on CRT displays and LCDs: observer performance and vision model predictions

RATIONALE AND OBJECTIVES

Although cathode-ray tube (CRT) displays typically are used for softcopy display of radiographs in the digital reading environment, liquid crystal displays (LCDs) currently are being used as an alternative. LCDs have many desirable viewing properties compared with a CRT, but significant image degradation can occur with off-axis viewing. This study compares observer performance and predictions from a human visual system model for on-axis and off-axis viewing for CRT displays versus LCDs.

MATERIALS AND METHODS

A set of mammograms with different lesion contrasts (n = 400) were shown to six radiologists on CRT and LCD monitors, once on-axis and once off-axis. Observer performance was measured by using receiver operating characteristic techniques. Performance was correlated with results of a human vision model designed to predict observer performance (just noticeable difference [JND]metrix model). Two approaches were used to generate model metrics; a paired discrimination and channelized model observer approach.

RESULTS

The performance of human observers indicated that on-axis viewing with the LCD was better than with the CRT, but off-axis viewing was significantly better with the CRT than LCD (F = 8.8175; P < .0001). The paired discrimination model correctly predicted on-axis, but not off-axis, results. The channelized model observer correctly predicted both on- and off-axis results.

CONCLUSION

Off-axis viewing of radiographic images on an LCD monitor degrades human observer performance significantly compared with a CRT display. Care should be taken in the clinic to avoid off-axis viewing during diagnostic interpretation.

Ergonomics of digital imaging

There has been an increase in the use of digital imaging in recent years and radiologists have almost universally accepted the use of computers in their day-to-day work. Completely filmless radiology departments, with all reporting being done on visual display terminals and picture archiving and communications systems (PACS) around the department, are already a reality in many places in the UK and other parts of the world. There is a constant need of computers for literature searches on the web, e-mails, communication and preparing lectures and presentations. With this explosive increase in the use of computers in the hospital, it is imperative that the use of computer monitor screens for medical use is optimized in order to avoid eyestrain and fatigue. This is especially important as tired eyes and brains may be more likely to commit errors. We have reviewed the current literature to elaborate a few useful measures that can be taken to minimize the effect of excessive computer use in a soft-copy radiology reporting area on the eyes and the musculoskeletal system. We recommend that optimal placement of computer monitors with user-friendly PACS terminal interfaces will ensure greater acceptability and improve reporting efficiency and accuracy. Good work practices to ensure reduction of reporting errors are highlighted.

Use of a human visual system model to predict observer performance with CRT vs LCD display of images

This Project evaluated a human visual system model (JNDmetrix) based on just noticeable difference (JND) and frequency-channel vision-modeling principles to assess whether a Cathode ray tube (CRT) or a liquid crystal display (LCD) monochrome display monitor would yield better observer performance in radiographic interpretation. Key physical characteristics, such as veiling glare and modulation transfer function (MTF) of the CRT and LCD were measured. Regions of interest from mammographic images with masses of different contrast levels were shown once on each display to six radiologists using a counterbalanced presentation order. The images were analyzed using the JNDmetrix model. Performance as measured by receiver operating characteristic (ROC) analysis was significantly better overall on the LCD display (P = 0.0120). The JNDmetrix model predicted the result (P = 0.0046) and correlation between human and computer observers was high (r (2) (quadratic) = 0.997). The results suggest that observer performance with LCD displays is superior to CRT viewing, at least for on-axis viewing.