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Current developments in storage solutions, PACS, and client-server systems allow for 3D imaging at the desktop. This can be achieved together with full storage into PACS of all slices, including the very large thin-section CT datasets. This paper describes a possible setup, which has been in operation for several years now, in response to an article by Meenan et al. previously published in this journal (1). [ABSTRACT FROM AUTHOR]

INTRODUCTION: Digital correction of the magnification factor is expected to yield more accurate and reliable preoperative plans. We hypothesized that digital templating would be more accurate than manual templating for total hip and knee arthroplasties. PATIENTS AND METHODS: Firstly, we established the interobserver and intraobserver reliability of the templating procedure. The accuracy and reliability of digital and analog plans were measured in a series of 238 interventions, which were all planned using both techniques. RESULTS: Interobserver reliability was good for the planning of knee arthroplasties (e-values 0.63-0.75), but not more than moderate for the planning of hip arthroplasties (e-values 0.22-0.54). Analog plans of knee arthroplasties systematically underestimated the component sizes (1.1 size on average), while the digital procedure proved to be accurate (0.1-0.4 size too small on average). The following figures show percentage of cases receiving a correct implant, allowing an error of one size. Digital templating of the hip arthroplasty was less frequently correct (cemented cup and stem: 72% and 79%; uncemented cup and stem: 52% and 66%) than analog planning (cemented cup and stem: 73% and 89%; uncemented cup and stem: 64% and 52%). INTERPRETATION: Planning of component sizes for total knee arthroplasties is an accurate procedure when performed digitally. Our digital preoperative plans which were performed by someone other than the surgeon were less accurate than the analog plans prepared by the surgeon. [ABSTRACT FROM AUTHOR]

Background: Magnetic resonance coronary angiography is challenging because of the motion of the vessels during cardiac contraction and respiration. Additional challenges are the small calibre of the arteries and their complex three dimensional course. Respiratory gating, turboflash acquisition, and volume rendering techniques may meet the necessary requirements for appropriate visualisation.Objective: To determine the diagnostic accuracy of respiratory gated magnetic resonance imaging (MRI) for the detection of significant coronary artery stenoses evaluated with three dimensional postprocessing software.Methods: 32 patients referred for elective coronary angiography were studied with a retrospective respiratory gated three dimensional gradient echo MRI technique. Resolution was 1.9 x 1.25 x 2 mm. After manual segmentation three dimensional evaluation was performed with a volume rendering technique.Results: Overall 74% (range 50% to 90%) of the proximal and mid coronary artery segments were visualised with an image quality suitable for further analysis. Sensitivity and specificity for the detection of significant stenoses were 50% and 91%, respectively.Conclusions: Volume rendering of respiratory gated MRI techniques allows adequate visualisation of the coronary arteries in patients with a regular breathing pattern. Significant lesions in the major coronary artery branches can be identified with a moderate sensitivity and a high specificity. [ABSTRACT FROM AUTHOR]

Intravenous coronary angiography with electron beam computed tomography (EBCT) allows for the non-invasive visualisation of coronary arteries. With dedicated computer hardware and software, three dimensional renderings of the coronary arteries can be constructed, starting from the individual transaxial tomograms. This article describes image acquisition, postprocessing techniques, and the results of clinical studies. EBCT coronary angiography is a promising coronary artery imaging technique. Currently it is a reasonably robust technique for the visualisation and assessment of the left main and left anterior descending coronary artery. The right and circumflex coronary arteries can be visualised less consistently. Improvements in image acquisition and postprocessing techniques are expected to improve visualisation and diagnostic accuracy of the technique. [ABSTRACT FROM AUTHOR]