Monitoring the PACS implementation process in a large university hospital--discrepancies between radiologists and physicians.

Successfully introducing a new technology in a health-care setting is not a walk in the park. Many barriers need to be overcome, not only technical and financial but also human barriers. In this study, we focus on the human barriers to health-care information systems' implementation. We monitored the acceptance of a Picture Archiving and Communication System (PACS) by radiologists and hospital physicians in a large Belgian university hospital. Hereto, questionnaires were taken pre-implementation (T1) and 1 year after the radiology department stopped printing film (T2). The framework we used to perform the study was the Unified Theory of Acceptance and Use of Technology. Main findings were that both groups were positive toward PACS prior to the introduction and that each group was even more positive at T2 with extensive PACS experience. In general, the ratings of the radiologists were higher than those of the physicians, as the radiologists experienced more of the benefits of PACS and had to use PACS throughout the day. Two factors were salient for predicting users' intention to use PACS: the usefulness of PACS (performance expectancy) and the availability of support of any kind (facilitating conditions). The results show that our approach was successful. Both radiologists and physicians give evidence of an excellent level of user acceptance. We can conclude that the implementation of PACS into our hospital has succeeded.

Image quality performance of liquid crystal display systems: influence of display resolution, magnification and window settings on contrast-detail detection.

The aim of this study was to investigate the combined effects of liquid crystal display (LCD) resolution, image magnification and window/level adjustment on the low-contrast performance in soft-copy image interpretation in digital radiography and digital mammography. In addition, the effect of a new LCD noise reduction mechanism on the low-contrast detectability was studied. Digital radiographs and mammograms of two dedicated contrast-detail phantoms (CDRAD 2.0 and CDMAM 3.4) were scored on five LCD devices with varying resolutions (1-3- and 5-megapixel) and one dedicated 5-megapixel cathode ray tube monitor. Two 5-megapixel LCDs were included. The first one was a standard 5-megapixel LCD and the second had a new (Per Pixel Uniformity) noise reduction mechanism. A multi-variate analysis of variance revealed a significant influence of LCD resolution, image magnification and window/level adjustment on the image quality performance assessed with both the CDRAD 2.0 and the CDMAM 3.4 phantoms. The interactive adjustment of brightness and contrast of digital images did not affect the reading time, whereas magnification to full resolution resulted in a significantly slower soft-copy interpretation. For digital radiography applications, a 3-megapixel LCD is comparable with a 5-megapixel CRT monitor in terms of low-contrast performance as well as in reading time. The use of a 2-megapixel LCD is only warranted when radiographs are analysed in full resolution and when using the interactive window/level adjustment. In digital mammography, a 5-megapixel monitor should be the first choice. In addition, the new PPU noise reduction system in the 5-megapixel LCD devices provides significantly better results for mammography reading as compared to a standard 5-magapixel LCD or CRT. If a 3-megapixel LCD is used in mammography setting, a very time-consuming magnification of the digital mammograms would be necessary.

fMRI of developmental stuttering: a pilot study.

The purpose of this investigation was to explore the feasibility of fMRI in the study of developmental stuttering. Speech contrasts (loud versus silent reading) and language contrasts (reading of semantically meaningful text versus nonsense words) of six developmental stutterers and six nonstutterers were compared using a commercial 1 Tesla MR-Scanner (Siemens Expert). Results indicate that mapping cortical function in persons who stutter is indeed feasible, even with a 1TMR-system. Compared to normals the stutterers seemed to employ different and particularly less differentiated auditory and motor feedback strategies in speech. They apparently rely on auditory processing and on cerebellar contribution as much during silent reading as during reading aloud. Moreover, they showed a greater involvement of the right hemisphere in language processing, activating not only the typical language areas on the left but also and with equal magnitude the right side homologues of these areas. In spite of the promising results, at present several practical problems such as possible movement artifacts and possible masking through scanner noise still hamper a more straightforward use of fMRI in the study of developmental stuttering.