Håkan Geijer

..The VGA scores were -0.28 for the color and -0.25 for the monochrome display (p = 0.24; NS). It thus seems possible to use color displays in diagnostic radiology provided that grayscale adjustment is used...

..The flat-panel detector has a very favourable combination of image quality vs radiation dose compared with storage phosphor plates and screen film...

..However, this cannot be done with automatic exposure, which is set for a constant detector dose...

..This leads to a lower effective dose and/or increased image quality depending on the settings chosen. The factorial experiments provided a powerful way to evaluate several parameters concomitantly...

..Radiation dose to patient and operator in PCI is heavily dependent on both equipment set-up and operating parameters which can be influenced by the operator. With a careful optimization, a large reduction of radiation dose is possible...

..The KAP for digital acquisition did not change significantly. It is possible to make a large dose reduction in PCI by reducing the fluoroscopy dose rate. This dose reduction is beneficial for both patients and staff...

..The optimization resulted in a dose reduction to 31% of the original effective dose with an acceptable reduction in image quality considering the intended use of the images for angle measurements...

..001). DAP does not increase when using radial instead of femoral access and the patients grade discomfort and pain much lower when using radial access. Radial access is thus beneficial to use...

..This cineangiographic and intravascular ultrasound (IVUS) substudy examined possible mechanisms...

..IN SUMMARY: This thesis indicates the possibility of dose reduction in diagnostic radiology through optimization of the radiographic process...

..The objective of the present study was to develop a reader independent urinary calculus segmentation algorithm using well-known digital image processing steps and to validate the method against size estimations by several readers...

..With the recent introduction of a second generation of DECT, there is a possibility of obtaining VNC images with better image quality at hopefully lower radiation dose compared to the previous generation...

..Two catheters are used in a coaxial fashion. It was possible to catheterize a patient with a 9 cm wide ascending aorta...

..Performing a factorial experiment gave an overview of how the image quality was influenced by image processing. By adjusting the level of noise compensation, unsharp masking and kernel, the IQF was improved to a 30% lower effective dose...

..The results of our study show equality of the evaluated preparation methods and cannot justify further use of bowel purgation before excretory urography...

..To evaluate the radiation dose, image quality, and Cobb angle measurements obtained with a digital scanning method of scoliosis radiography...

..A substantial dose reduction was obtained with this new direct digital detector. This simple but efficient optimisation approach is easily applicable to other examinations and both DDD and storage phosphor plate detectors...

..To compare radiation doses given to patients undergoing IVU (intravenous urography) before and after digitalization of our X-ray department...

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..Equivalent image quality in image pairs was achieved at 30% of the dose. The CDRAD contrast-detail phantom makes it possible to find dose levels that give equal image quality using different imaging systems...

..To evaluate a technique for closure of a femoral artery access in which the cribriform fascia covering the common femoral artery is sutured...

..Conventional harvesting of the saphenous vein in coronary artery bypass surgery produces vessel damage that contributes to graft failure. A novel "no touch" technique provides high short- and long-term patency rates...

..If the same patients had been treated using dedicated angiographic equipment, the risk of skin injury would be much higher. It is thus important to be aware of the dose output of the equipment that is used...

..To evaluate the usefulness of M-mode measurement of circumflex artery motion (CAM) for assessment of left ventricular (LV) function...

..The objectives of this study were to quantify the impact of image post-processing parameters on the apparent renal stone size, and to quantify the intra- and inter-reader variability in renal stone size estimation...