Search results for "x-ray"
showing 10 items of 4234 documents
Long-term bony integration and resorption kinetics of a xenogeneic bone substitute after sinus floor augmentation: histomorphometric analyses of huma…
2013
In this case series, a systematic histomorphometric analysis of two human bone biopsy specimens was conducted 1 and 5 years after grafting with a xenogeneic bovine bone substitute material (BSM). While the 1-year specimen still showed extensive signs of an active desmal ossification, the specimen after 5 years mainly showed mature lamellar bone without bone turnover or remodeling. A completed bony integration without extensive resorption of the BSM particles could be detected. Altogether, a good integration in the bone with osteoconduction and a high biocompatibility was seen.
Ultrastructural study by backscattered electron imaging and elemental microanalysis of biomaterial-to-bone interface and mineral degradation of bovin…
2012
Objectives The aim of this study was to perform an ultrastructural study of the bone-to-biomaterial interface and biomaterial mineral degradation in retrieved bone biopsies following maxillary sinus augmentation using bovine xenografts (Endobon®) in 15 clinical cases. Materials and methods Nine months after sinus lifting, bone cores were harvested from the maxillary sinus. The specimens were processed for observation under a scanning electron microscope with backscattered electron imaging (SEM-BSE). In addition, chemical analysis and elemental mapping of the mineral composition were generated using a microanalytical system based on energy-dispersive X-ray spectrometry (EDX). Results No clin…
Computed tomography-based tracheobronchial image reconstruction allows selection of the individually appropriate double-lumen tube size
1999
Objectives: To determine whether individualized selection of double-lumen tubes or alternatives based on three-dimensional reconstruction of the tracheobronchial image from routine preoperative computed tomography (CT) scans leads to clinically appropriate choices. Design: Prospective observational study; comparison to historic controls. Setting: Anesthesia and radiology facilities of a university medical center. Participants: Forty-nine patients undergoing thoracic surgery requiring one-lung ventilation. Interventions: Three-dimensional image reconstruction of individual tracheobronchial anatomy was performed from routine preoperative spiral CT scans as well as from scans of five left-side…
Statement of severe trauma management in France; teachings of the FIRST study
2013
Abstract Introduction The blunt trauma victim management is still a matter of debate and comparing studies involving different emergency medical services and health care organization remains fictitious. Hence, the French Intensive care Recorded in Severe Trauma (FIRST) was conducted in order to describe the severe blunt trauma management in France. The present paper aimed at recalling the main results of FIRST study. Methods The FIRST study was based on a multicenter prospective cohort of patients aged 18 or over with severe exclusive blunt trauma requiring admission to university hospital care unit within the first 72 h and/or managed by medical-Staffed Emergency Mobile Unit (SMUR). Multip…
Stone-Free Rate after Treating Kidney Stones Exceeding 10 mm via Flexible Ureteroscopy: Can Endoscopic Assessment Replace Low-Dose Computed Tomograph…
2019
<b><i>Introduction:</i></b> It is unclear whether endoscopic assessment of the stone-free rate after flexible ureteroscopy (fURS) is as effective as assessment with low-dose computed tomography (CT) scan. <b><i>Methods:</i></b> Prospective documentation of patients with kidney stones &#x3e; 10 mm diameter from 2 different centers (Freiburg, Regensburg), who underwent fURS and were declared to be endoscopically completely stone-free. Low-dose CT control performed 4–8 weeks postoperatively. <b><i>Results/Conclusion:</i></b> Thirty-eight patients were treated between October 2015 and August 2016 (12 F, 26 M). Average a…
Efficacy of single-source rapid kV-switching dual-energy CT for characterization of non-uric acid renal stones: a prospective ex vivo study using ant…
2019
Purpose To investigate the accuracy of rapid kV-switching single-source dual-energy computed tomography (rsDECT) for prediction of classes of non-uric-acid stones. Materials and methods Non-uric-acid renal stones retrieved via percutaneous nephrolithotomy were prospectively collected between January 2017 and February 2018 in a single institution. Only stones >= 5 mm and with pure composition (i.e., >= 80% composed of one component) were included. Stone composition was determined using Fourier Transform Infrared Spectroscopy. The stones were scanned in 32-cm-wide anthropomorphic whole-body phantom using rsDECT. The effective atomic number (Zeff), the attenuation at 40 keV (HU40), 70 ke…
Anatomical correlates of visual and tactile extinction in humans: a clinical CT scan study.
1994
The anatomical correlates of tactile and visual extinction with double simultaneous stimulation were investigated in a series of 159 patients with right brain damage caused by stroke. Forty six patients showed extinction (22 tactile, 14 visual, 10 tactile and visual). Over 50% of the patients with extinction had deep lesions, which were found in about 25% of the patients with visuospatial neglect not associated with extinction. In the patients with extinction and cortico-subcortical damage the paraventricular occipital white matter and the dorsolateral frontal cortex were most often involved. By contrast, when neglect was also present, the lesions clustered in the inferior parietal lobule. …
Evidence of noncentrosymmetry of human tooth hydroxyapatite crystals
2014
Herein, we investigate human single hydroxyapatite crystals (enamel and dentine) by convergent-beam electron diffraction (CBED) and automated electron-diffraction tomography (ADT). The CBED pattern shows the absence of the mirror plane perpendicular to the c axis leading to the P63 space group instead of the P63 /m space group considered for larger-scale crystals, this is confirmed by ADT. This experimental evidence is of prime importance for understanding the morphogenesis and the architectural organization of calcified tissues.
Hamartoma of the urinary bladder: case report and review of the literature.
1999
Bladder hamartoma is a rare benign entity with only eight cases reported in the literature thus far, and whose general imaging features have not, to our knowledge, been previously discussed. The purpose of this report is to review the literature and to discuss the imaging findings in one case of bladder hamartoma where US features were those of an inhomogeneous solid mass with an unechogenic center, which was in accordance with the CT findings of a soft tissue mass with central inhomogeneous enhancement due to central necrosis.
Quantitative analysis of emphysema in 3D using MDCT: Influence of different reconstruction algorithms
2008
Abstract Purpose The aim of the study was to compare the influence of different reconstruction algorithms on quantitative emphysema analysis in patients with severe emphysema. Material and methods Twenty-five patients suffering from severe emphysema were included in the study. All patients underwent inspiratory MDCT (Aquilion-16, slice thickness 1/0.8 mm). The raw data were reconstructed using six different algorithms: bone kernel with beam hardening correction (BHC), soft tissue kernel with BHC; standard soft tissue kernel, smooth soft tissue kernel (internal reference standard), standard lung kernel, and high-convolution kernel. The only difference between image data sets was the algorith…