International Nuclear Information System (INIS)

Eleven patients who had undergone cardiac surgery were studied by means of high-field MR imaging (1.5 T). Six patients had aortic root and valve replaced with a Bjork-Shiley (BS) composite tubular aortic graft prosthesis for acute dissection of ascending aorta. In the other 5 patients with rheumatic calcific aortic disease, the valve had been replaced with a BS prosthesis. As a whole, MR studies were 14. Previous evaluations of magnetic field effects had seem carried out ex vivo on both BS valves and BS composite prostheses, on surgical ligation clips (Tantalium and Stainless) and on stainless wires for sternal closure. In 4 patients (2 BS composite grafts, and 2 BS valves) MRI diagnosed chronic dissection of both arch and descending aorta. In 1 of them, with a bs valve, associated localized acute dissection of ascending aorta was observed. In 3 patients with BS composite grafts, MRI revealed ...

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The evaluate the signs of aortic intramural hematoma with helical CT and the diagnostic role of this technique in patients with this condition. It was reviewed the CT findings of 396 patients submitted to emergency examinations for suspected aortic dissection from 1995 to 1999. Only 18 patients (6 women and 12 men) had CT signs of aortic intramural hematoma. Helical CT studies were carried out with the following parameters: slice thickness 10 mm, reconstruction index 10, feed 1.5 mm, conventional algorithm with minimum values of 130 kV and 125mA. All patients were examined with dynamic contrast-enhanced CT, before and after a power injection of 130 mL ionic contrast material. It was studied: hematoma localization and longitudinal extension; thickness and density of aortic wall; presence and location of intimal calcifications; integrity of intimal wall; hemo mediastinum and/or hemo ...

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We retrospectively studied the computed tomography scans of the orbit in 75 patients in order to identify the presence of incidental calcifications (scleral and trochlear apparatus calcifications.). These imaging findings should integrate the vast list of differential diagnosis of orbital calcifications, as they may help radiologists to distinguish these calcifications from orbital foreign bodies. (author)

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Peritoneal calcification, which can lead to intestinal obstruction and potentially lethal hemoperitoneum, is a rare complication of continuous ambulatory peritoneal dialysis. We describe a case in which extensive peritoneal calcification had arisen for this reason. Although the patient was asymptomatic, extensive calcification was present on the parietal and visceral peritoneum, including the hepatic and splenic surface. (author)

UK PubMed Central (United Kingdom)

AimsTwo-dimensional echocardiographic (2DE) continuity-equation derived aortic valve area (AVA) in aortic stenosis (AS) relies on non-simultaneous measurement of left ventricular...Full Text Available

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Fuji Computed Radiography (FCR) was evaluated for detection of intracardiac calcification as compared with conventional radiography in 77 patients. Intracardiac calcification was found in 37 patients (left coronary artery: 31, right coronary artery: 11, valve: 9) on cine-fluorography. The sensitivity for detecting these calcified foci with FCR was higher than conventional screen-film method. Especially, sensitivity for detecting left coronary artery calcification with FCR was significantly higher than conventional method (71 %, 32 %) (p < 0.01), Fine anatomical details of calcification were well shown on FCR. Chest radiography using FCR is of great use for detection of intracardiac calcification. (author).

UK PubMed Central (United Kingdom)

Six children who received craniospinal irradiation for medulloblastoma when they were under 10 years of age developed learning disabilities. Four exhibited associated temporal lobe calcification on...Full Text Available

UK PubMed Central (United Kingdom)

Thoracic aortic aneurysms (TAAs) are potentially devastating, and due to their asymptomatic behavior, pose a serious health risk characterized by the lack of medical treatment options and high...Full Text Available

UK PubMed Central (United Kingdom)

Anionic microdomains within the aortic smooth muscle cell (SMC) surface glycocalyx represent a potential barrier to the endocytosis of anionic plasma proteins. Cultured SMCs exposed briefly to cationized...Full Text Available

UK PubMed Central (United Kingdom)

This is a report of surgical treatment of thoracoabdominal aortic aneurysms and aneurysms of the abdominal aorta from which the visceral vessels arise during the 18 year period from April 5, 1960,...Full Text Available

UK PubMed Central (United Kingdom)

OBJECTIVE—Identification of arterial genes and pathways altered in obesity and diabetes.RESEARCH DESIGN AND METHODS—Aortic gene expression profiles of...Full Text Available

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Dynamic CT and MRT were performed in 21 patients who had undergone prosthetic replacement of the aorta because of dissection of the thoracic aorta. There is no difference between MRI and dynamic CT in the demonstration of a persistent intimal flap, the formation of a thrombus and the assessment of the aortic diameter in patients who underwent surgery for thoraco-abdominal aortic dissection. MRI, however, is superior in the identification of the true and false lumen and the demonstration of the distal anastomotic site. The major advantages of MRI are that there is no need for intravenous contrast agents, that it is high sensitive to flow phenomena, and that it can demonstrate the aortic arch and the ascending aorta on sagittal oblique sections. The major disadvantages of MRI are the limited access to the patient during the procedure, and the inability to examine patients fitted with pacemakers or who are on assisted ...

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Bone images obtained by single exposure dual energy subtraction with computed radiography, a new image processing method, were evaluated for the detectability of calcification in lung nodules in both phantom and clinical studies. In the phantom study, five simulated nodules containing known and uniformly distributed amounts of calcium hydroxide were placed in a human chest phantom and images were obtained the following five techniques: 1) conventional radiography (CXR), 2) low kV conventional radiography (Low), 3) Fuji computed radiography (FCR), 4) bone images with conventional singles exposure energy subtraction (ES) and 5) bone image with fine single exposure energy subtraction (FES). The detectability of calcification in the simulated nodules was evaluated by six radiologists using ROC analysis and two-way analysis of variance. In the clinical study, images of 42 lung nodules (21 calcified lung nodules and 21 non-calcified nodules), in ...

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In order to investigate the role of mononuclear cells in infiltrates during the initial stages of atherogenesis, the authors have studied by immunohistochemical methods the aortas and coronary vessels...Full Text Available

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BackgroundWave reflection during the systole increases left ventricular (LV) pressure, tension-time index (TTI) and myocardial oxygen requirement. The purpose of this study was to extract that component of extra myocardial oxygen requirement that is due to early systolic wave reflection, define it as wasted effort (?Ew), and examine its relationship to LV hypertrophy (LVH).MethodsRadial artery pressure waveforms were recorded using applanation tonometry and central aortic waveforms generated in 98 patients with untreated hypertension. Aortic augmentation index (AIa), wave reflection amplitude (i.e., aortic augmented pressure (AG)) and systolic duration (ED?Tr), ejection duration (ED) and round-trip travel time of the pressure wave (Tr) were calculated from the aortic waveform, a...

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Aim of the work was to describe computerised tomography (CT) findings of calcified renal metastases focusing on differential diagnosis problems. Abdominal CT scans of 8000 patients with tumor, performed from 1984 to 1998, have been retrospectively reviewed. [Italian] Scopo del lavoro e' quello di descrivere gli aspetti con tomografia computerizzata delle metastasi renali calcificate enfatizzando le problematiche diagnostico differenziali. Sono state valutate retrospettivamente le indagini TC addominali di 8000 pazienti affetti da tumore nel periodo 1984-1998, analizzando le lesioni calcificate riscontrate.

UK PubMed Central (United Kingdom)

A 65-year-old man suffering from ascending aorta aneurysm and atherosclerotic three vessel disease without left main involvement underwent aortic root replacement with coronary ostia reimplantation...Full Text Available

UK PubMed Central (United Kingdom)

We report a case of chylopericardium after ascending aorta and aortic valve replacement, which presented as late tamponade. We discuss the various treatment options in this rare condition which can...Full Text Available

UK PubMed Central (United Kingdom)

The increased risk of thrombosis in patients with active cancer has multiple causes. Acute thrombosis of the aorta is an exceedingly rare but potentially devastating complication in patients with cancer...Full Text Available

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The advent, in the near future, of compact X-ray sources like Thomson Back-Scattering (TBS) will allow the clinical application of advanced X-ray imaging techniques, such as phase contrast, with higher sensitivity and lower impact in terms of dose delivery. In this work, we theoretically investigated the possibility of using such sources for phase contrast imaging of micro-calcifications included in a breast tissue. In our study we analyzed the phase and amplitude distribution of the TBS source and we showed that this source can be used for phase contrast imaging since the source coherence at the sample position is sufficiently high for achieving good contrast and micrometer spatial resolution. Indeed the spatial coherence of a TBS source is closer to that of a synchrotron radiation source, and much better than that of a laboratory source. Moreover, we showed the advantages of phase imaging with respect to standard absorption imaging, in the specific case of ...

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BackgroundEchocardiography has been debated as an adjunct for transcatheter aortic valve replacement (TAVR). The aim of this prospective study was to comparatively evaluate intraprocedural guidance using intracardiac echocardiography (ICE) and transesophageal echocardiography (TEE). MethodsFifty high-risk patients with severe aortic stenosis scheduled for TAVR were randomized to either guidance using ICE (group 1; n = 25) or monitoring using TEE (group 2; n = 25). ResultsIn contrast to TEE, ICE allowed continuous monitoring. The need for probe repositioning during the procedure was much lower in group 1 (0.1 +- 0.3 vs 5.7 +- 0.7 maneuvers, P P = .003). Both coronary ostia were more frequently visualized in group 1 (18 vs 2 cases, P n = 25, r2 = 0.90, P n = 11, P = .012), but ICE did not (m...

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Computed tomography was performed on 5 patients with chronic cerebral paragonimiasis. CT showed solitary or multiple, amorphous, round, or oval calcifications, and ventricular enlargement in all 5 cases. A large low-density area is also found in 4 of the 5 cases. These CT findings are compatible with previously reported findings of simple X-ray films of the skull, pneumoencephalography, and pathological studies. (author).

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Platelet deposition on bovine pericardial-tissue mitral-valve prostheses in 11 dogs was observed noninvasively by use of "1"1"1In-labeled platelets and quantified after sacrifice at one (n . 3), 14 (n . 3), and 30 (n . 5) days postimplantation (300-400 microCi of labeled platelets having been injected 24 hours previously). Thrombosis on the sewing ring and pericardial leaflets at one and 14 days and on the leaflets at 30 days was delineated in scintiphotos. In vitro quantification (% injected dose) indicated that the leaflets, sewing ring, and perivalvular tissue retained 0.904% of labeled platelets at one day postimplantation, 0.198% at 14 days, and 0.040% at 30 days. Platelet half-life was reduced to 38 hours at 21 days postimplantation but returned toward the normal (50 hours) with fibrous ingrowth in the sewing ring. Microembolism in lung and kidney, as measured by tissue/blood radioactivity ratio, also was decreased significantly at 30 days. "1"1"1In-labeled platelets thus provide ...

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Forty-one cases of mediastinal tumor examined by computed tomography were reviewed. CT findings of the mediastinal malignancy were as follows: 1) inhomogeneous density on contrast CT, 2) equivocaton of fat plane surrounding the tumor, 3) irregular margin. Benign teratoma had smooth margin and included fat or calcification density. Mediastinal seminoma was observed as a lobulated mass with no calcification on CT. These findings were similar to the patterns of malignant thymoma or lymphoma. Consequently, it was very difficult to differentiate between malignant thymoma and malignant lymphoma by CT. According to our data, malignant thymoma tended to expand to only one side of the anterior mediastinum and to invade the anterior chest wall. On the other hand, malignant lymphoma of anterior medistinal type expanded into the trachea and the superior vena cava. In patients with sarcoidosis, the enlargement of bilateral hilar lymph nodes was commonly ...

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Periureteral or subtrigonal injection of dextranomer/hyaluronic acid (Dx/HA) copolymer (Deflux, Q-Med, Uppsala, Sweden) is an increasingly common endoscopic treatment for vesicoureteral reflux. We report a confusing radiographic finding of bilateral calcified Dx/HA injections initially thought to represent bilateral distal ureteral stones in a boy who presented with intermittent periumbilical pain. Urologists, radiologists, and emergency room physicians should be aware of the potential for calcification of ureteral implants of Dx/HA, and of the potentially confusing radiographic images that may result. (orig.)

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Tc-MDP 10mCi was intravenously given preoperatively to 20 patients with primary bone tumors and 1 with a metastatic bone tumor. Preoperative and postoperative scintigraphs of resected tumor and scintigraphs of sliced tumor were compared. Tissue fragments were collected from the sliced tumor, and RI measured to compare concentration rates at different areas. Histological investigations were also done. Localization of Tc-MDP was increased at sites of tumorous bone formation, of reactive bone formation at tumor edges, and of cartilage calcification, with little concentration at tumor cells or necrotic tissue. VX/sub 2/ carcinoma was transplanted into the rabbit tibia, Tc-MDP was intravenously injected when bone destruction was radiologically evident, and investigations were done as in the clinical cases. In experimental bone tumor, increased uptake localization of Tc-MDP was much the same as in clinical cases. Tetracycline was given to the rabbit of Experiment to ...

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While trauma is still the leading cause of death in the pediatric age range, it is surprising how little the CT appearances of pediatric chest injury have been investigated in the literature. We have reviewed the CT findings of blunt chest trauma in 44 children for whom chest CT examinations were requested to investigate the extent of intrathoracic injury. We noted a propensity for pulmonary contusions to be located posteriorly or posteromedially, and for them to be anatomically nonsegmental and crescentic in shape. This is possibly attributable to the relatively compliant anterior chest wall in children. The CT appearances of other major thoracic injuries are described, including pulmonary lacerations, pneumothoraces, malpositioned chest tubes, mediastinal hematomas, aortic injury, tracheobronchial injury, hemopericardium, and spinal injuries with paraspinal fluid collections. Children demonstrating findings incidental to the actual injury yet important to the ...

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Anesthetic techniques vary widely in the endovascular repair of abdominal aortic aneurysms (EVAR). Previous studies have demonstrated the feasibility of using local anesthesia. However, the ideal anesthetic technique has not been determined. This study examines whether anesthesic technique influences the outcomes of EVAR. Data regarding demographics, risk factors, procedural characteristics, recovery characteristics, treatment complications, acute ( 0.05, ANOVA). From these results we concluded that EVAR with local anesthesia is a safe and efficacious method that may reduce recovery times and postoperative medical morbidity compared to use of genera1 or spinal/epidural anesthesia.

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Background Limited data is available for investigating the long-term safety and effects of intracoronary progenitor cell therapy in patients with acute myocardial infarction (AMI). Objective To assess the clinical course, NT-proBNP and MRI data as objective markers of cardiac function of the TOPCARE-AMI patients at 5-year follow-up. Design The TOPCARE-AMI trial was the first randomized study investigating the effects of intracoronary infusion of circulating (CPC) or bone marrow-derived progenitor cells (BMC) in 59 patients with successfully reperfused AMI. Results Five-year follow-up data were completed in 55 patients, 3 patients were lost to follow-up. None of the patients showed any signs of intramyocardial calcification or tumors at 5?years. One patient died during the initial hospitali...

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Twenty-three patients with intracranial meningiomas were examined by means of magnetic resonance tomography (MRT). In 13 patients the paramagnetic contrast medium gadolinium DTPA was used. Meningiomas show only slight changes in signal intensity compared with brain in the spin-echo mode, the greatest contrast being found on photon density images (TR 1600 ms, TE 35 ms). In T1 images more than 50% of the patients showed a low signal margin between tumour and brain. Hyperostosis of the calvarium is easily recognised, but MRT is unreliable for showing tumour calcification. After intravenous injection of gadolinium DTPA, there was marked homogeneous uptake in the meningiomas. These signs are useful for the diagnosis of a meningioma by MRT. (orig.).

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The authors carried out a retrospective study on 4 years' work on a series of patients with proved active tuberculosis examined in the Departments of Bronchopneumology and Infectious Disease of the Arezzo Civil Hospital. The population was heterogenerous from the immunologic viewpoint. This paper compared the effectiveness of Computed Tomography (CT) with that of conventional chest radiography (CR) in the diagnosis and prognosis of tuberculosis. All patients underwent chest CR in double projection and conventional CT studies of the chest; 16 patients were also submitted to high resolution CT (HRCT). Consolidation was the most frequent parenchymal lesion in immunocompetent patients; it was often associated with cavitation, with no clear topographic prevalence in the upper lobes. Pleural effusion, as the only sign of disease and with empyema features, was found in 10 immunocompetent patients. No predominant pattern was found in the other two groups, even though intrathoracic adenopathies ...

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Purpose To study the activation and expression of vascular (aorta and small mesenteric arteries) potassium channels during septic shock with or without modulation of the NO pathway. Methods Septic shock was induced in rats by peritonitis. Selective inhibitors of vascular KATP (PNU-37883A) or BKCa [iberiotoxin (IbTX)] channels were used to demonstrate their involvement in vascular hyporeactivity. Vascular response to phenylephrine was measured on aorta and small mesenteric arteries mounted on a wire myograph. Vascular expression of potassium channels was studied by PCR and Western blot, in the presence or absence of 1400W, an inducible NO synthase (iNOS) inhibitor. Aortic activation of the transcriptional factor nuclear factor-kappaB (NF-?B) was assessed by electrophoretic mobility shift as...

British Library Electronic Table of Contents (United Kingdom)

Ventricular septal defects can occur as part of other congenital cardiac malformations or as an isolated finding. Aneurysms of the sinus of Valsalva are rare, most commonly involving the right or noncoronary sinuses. They can be congenital or acquired through infection, trauma, or degenerative diseases. They frequently co-exist with ventricular septal defects, aortic valve dysfunction, or other cardiac abnormalities. More commonly, sinus of Valsalva aneurysms are diagnosed after the clinical sequelae of rupture. Several etiologic factors may lead to the development of pathologic pericardial effusion and the detection of pericardial effusion was one of the first applications of echocardiography to gain widespread acceptance. We present a case of a chance finding of an aneurysm of the right ...

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Eight patients with double-velour Dacron aorto-femoral grafts implanted for 2-60 months were studied. Indium-111-labelled platelets were found to have a shortened mean platelet lifespan (MPLS) of 138 +- 32 hours compared with the normal platelet lifespan of 224 +- 23 hours. Labelled platelets accumulated on all grafts, irrespective of graft age, to a maximum of 1,80 +- 0,83% of whole body radioactivity; thereafter graft radio-activity decreased. This suggests that platelets on the graft are in dynamic equilibrium with those in the circulation. Platelets may be lost from the graft by embolization or radioactivity may be released because of platelet lysis. Although MPLS may depend on the age and surface area of the graft, concomitant arterial disease probably also contributes to the shortened MPLS.

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The objective of this study was to compare contrast-enhanced magnetic resonance angiography (CE MRA) and multislice computed tomographic angiography (MS CTA) in the follow-up of thoracic stent-graft placement. The CE MRA and MS CTA were performed following nitinol stent-graft treatment due to thoracic aneurysm (n=4), intramural bleeding (n=2) and type-B aortic dissection (n=5). Corresponding evaluation of arterial-phase imaging characteristics focused on the stent-graft morphology and leakage assessment. Stent-graft and aneurysm extensions were comparable between both techniques. Complete exclusion (aneurysm, n=4; dissection, n=2) was assessed with high confidence with CE MRA and MS CTA. Incomplete exclusion (intramural bleeding, n=2; dissection, n=3) was assigned to lower confidence scores on CE MRA compared with MS CTA. On CE MRA the stent-graft lumen demonstrated an inhomogeneous signal, the stent struts could not be assessed. The CE MRA can be used as ...

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Glycosaminoglycans (GAG) are believed to be important in the pathogenesis of atherosclerosis. We have previously demonstrated that areas of injured aorta that have been re-endothelialized accumulate increased amounts of lipid and GAG when compared to areas remaining de-endothelialized. We have now examined the net incorporation of labeled precursors into the individual GAG present in both re-endothelialized and de-endothelialized areas of rabbit aorta. Aortic tissue was examined at 2-3 and 10-14 weeks after a denuding injury by incubating tissue minces with (/sup 3/H)glucosamine and sodium (/sup 35/S)sulfate for 24 hr. Following incubation, the aortic GAG were isolated and assayed for uronic acid concentration and radioactivity. Results indicate that the total GAG concentration was significantly greater in the re-endothelialized as compared to de-endothelialized areas. The concentration in uninjured aorta was 9.01. The difference between the ...

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A single exposure energy subtraction technique with a metal filter and an imaging plate for the Fuji Computed Radiography (FCR) system was developed for dual-energy subtraction radiography (DES) of the chest. By the use of this technique, 206 patients with suspected lung cancer were scanned in the clinical settings. The subtracted images in 200 patients, excluding six with poor image quality, were examined. Soft-tissue images (bone cancelled images) were useful in visualizing abnormality of the airway and nodules lying under the ribs; and bone images (soft-tissue cancelled images) in detecting rib metastases and the presence or absence of calcification in nodules. Additional information was acquired in 21 % (42/200). A single exposure is capable of neglecting motion artifacts. In addition, this technique may be of value in DES, which is considered to be one of the routine examinations, in view of low exposure doses. The need of conventional roentgenograph, in ...

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Purpose: The aim of this study was to demonstrate the typical appearance of ganglioneuromas in computer-assisted tomography (CT), and magnetic resonance imaging (MRI). Material and methods: Retrospective analysis of diagnostic imaging (9 CT, 6 MRI) in 9 children aged 3 to 15 years with the histological diagnosis of ganglioneuroma. Results: The tomographies showed large (max. 13.4 cm in diameter) round or oval tumors with sharp delineation. The sites of the tumors were the retroperitoneum (5), the mediastinum (3), and the adrenal gland (1). Intraspinal tumor involvement occurred in 4 cases. On comparing CT with MRI, MRI was more accurate in defining the intraspinal involvement. The ganglioneuromas were of hypodense appearance in the native CT scan and showed moderate enhancement upon administration of contrast media. In five patients tumor calcifications with a disseminated sprinkled pattern were seen in CT. In MRI T_1-weighted scans the tumors were homogeneous and ...

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Purpose: To assess the prevalence, significance and practical value of two recently described CT signs of instable aneurysm: the crescent sign and the periluminal halo (a low-attenuating internal layer of the thrombus around the patent lumen). Material and methods: Among the CT examination performed in the last 5 years, they retrospectively selected the nonruptured aneurysms with a diameter exceeding 4 cm (no. = 93 average diameter 5.1 cm, unenhanced images in 28 cases and enhanced in 84) and the ruptured aneurysms (no. = 16, average diameter 6.7 cm, unenhanced images in 9 cases and enhanced in 9). They studied the prevalence of the crescent and halo sing, their relationship with the aneurysm diameter, and the effect of contrast enhancement. Results: The crescent sign was identified with a statistically significant prevalence in ruptured ( 37.5 % or cases) over asymptomatic aneurysms (5.5 %); the halo had the same frequency in the 2 groups (12.5 % and 9.5 %). Both signs were more ...

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Micropatterned materials were obtained by a controlled laser ablation of a photoimmobilised homogeneous layer of hyaluronic acid (Hyal) and its sulphated derivative (HyalS). The photoimmobilisation was performed by coating the polysaccharide, adequately functionalised with a photoreactive group, on aminosilanised glass substrate and immobilising it on the surface under UV light. Hyal or HyalS photoimmobilised samples were then subjected to laser ablation with wavelengths in the UV regions in order to drill the pattern. Four different patterns with stripes of 100, 50, 25 and 10 {mu}m were generated. A chemical characterisation by attenuated total reflection/Fourier transform infrared (ATR/FT-IR) and time of flight-secondary ions mass spectrometry (TOF-SIMS) confirmed the success of the laser ablation procedure and the presence of alternating stripes of polysaccharide and native glass. The exact dimensions of the stripes were determined by atomic force microscopy. The analysis of cell ...

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The purpose was to compare the findings of multi-detector computed tomography (MDCT) in prosthetic valve disorders using the operative findings as a gold standard. In a 3-year period, we prospectively enrolled 25 patients with 31 prosthetic heart valves. MDCT and transthoracic echocardiography (TTE) were done to evaluate pannus formation, prosthetic valve dysfunction, suture loosening (paravalvular leak) and pseudoaneurysm formation. Patients indicated for surgery received an operation within 1 week. The MDCT findings were compared with the operative findings. One patient with a Bjoerk-Shiley valve could not be evaluated by MDCT due to a severe beam-hardening artifact; thus, the exclusion rate for MDCT was 3.2% (1/31). Prosthetic valve disorders were suspected in 12 patients by either MDCT or TTE. Six patients received an operation that included three redo aortic valve replacements, two redo mitral replacements and one Amplatzer ductal occluder occlusion of a ...

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Micropatterned surfaces with different chemical topographies were synthesised in order to investigate the influence of surface chemistry and topography on cell behaviour. The microstructured materials were synthesised by photoimmobilising natural Hyaluronan (Hyal) and its sulphated derivative (HyalS), both adequately functionalised with a photorective moiety, on glass substrates. Four different grating patterns (10, 25, 50 and 100 {mu}m) were used to pattern the hyaluronan. The micropatterned samples were analysed by Secondary Ions Mass Spectrometry, Scanning Electron Microscopy (SEM) and Atomic Force Microscopy to investigate the chemistry and the topography of the surfaces. The spectroscopic and microscopic analysis of the microstructured surfaces revealed that the photoimmobilisation process was successful, demonstrating that the photomask patterns were well reproduced on the sample surface. The influence of chemical topographies on the cell behaviour was then analysed. Human and ...

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The purpose of this study is to evaluate the radiologic findings of the extraosseous Ewing's sarcoma. Six patients with pathologically confirmed extraosseous Ewing's sarcoma were retrospectively reviewed. Patients included two men and four women with an average age of 21.5 years (age range 9-48 years). Plain radiographs (six patients), magnetic resonance (MR) images (five patients), computed tomographic (CT) scans (three patients) and whole body scintigraphy (two patients) were reviewed and analyzed. Images were evaluated with regard to lesion location, size, margin, muscle or bone involvement and intrinsic imaging characteristics on CT and MRI. The tumors were located in the thigh (three patients), back (two patients) and upper arm (one patient). The tumors ranged in size from 2.3 cm to 7.5 cm (mean, 5.2 cm), were mainly well circumscribed and showed no evidence of calcification prior to treatment. Margins were well defined in four out of the six patients. Four ...

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Full text: Disorders of brain development and phakomatosis are resulting from disturbed embryonic-foetal development One third of all major embryological anomalies involve CNS, and over 2000 different anomalies have been described. Anomalies of the brain often cause foetal and neonatal death, and mental and physical retardation in pediatric group. The majority of disorders of brain development and phakomatosis are idiopathic, and most of them are not hereditary or familial. Ultrasonography plays the important role in screening foetal and neonatal brain, but after closure of fontanels it is difficult to find the acoustic window. CT has limited contrast resolution, and disadvantage exposing infant to ionizing radiation. It is helpful to demonstrate the presence of calcifications. MR imaging has proved to be a diagnostic tool of major importance in children with disorders of brain development and phakomatosis. The excellent grey/white matter differentiation and ...

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Purpose: To assess the prevalence, significance and practical value of two recently described CT signs of instable aneurysm: the crescent sign and the periluminal halo (a low-attenuating internal layer of the thrombus around the patent lumen). Material and methods: Among the CT examination performed in the last 5 years, they retrospectively selected the nonruptured aneurysms with a diameter exceeding 4 cm (no. = 93 average diameter 5.1 cm, unenhanced images in 28 cases and enhanced in 84) and the ruptured aneurysms (no. = 16, average diameter 6.7 cm, unenhanced images in 9 cases and enhanced in 9). They studied the prevalence of the crescent and halo sing, their relationship with the aneurysm diameter, and the effect of contrast enhancement. Results: The crescent sign was identified with a statistically significant prevalence in ruptured ( 37.5 % or cases) over asymptomatic aneurysms (5.5 %); the halo had the same frequency in the 2 groups (12.5 % and 9.5 %). Both signs were more ...

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This study was designed to evaluate the influence of inhalational agents on the intestinal circulation in an isolated loop preparation. Sixty dogs were studied, using three intestinal segments from each dog. Selected intestinal segments were pumped with aortic blood at a constant pressure of 100 mmHg. A mixture of /sub 86/Rb and 9-microns spheres labeled with /sup 141/Ce was injected into the arterial cannula supplying the intestinal loop, while mesenteric venous blood was collected for activity counting. A very strong and significant correlation was found between rubidium clearance and microsphere entrapment (r = 0.97, P less than 0.0001). Nitrous oxide anesthesia was accompanied by a higher vascular resistance (VR), lower flow (F), rubidium clearance (Cl-Rb), and microspheres entrapment (Cl-Sph) than pentobarbital anesthesia, indicating that the vascular bed in the intestinal segment was constricted and flow (total and nutritive) decreased. Halothane, enflurane, ...

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A vessel phantom suitable for evaluation of spatial and contrast resolution of FCRDSA (Fuji Computed Radiography, digital subtraction angiography) has been developed and used for determining resolution. The effects of iodine concentration, low dose exposure, and acryl thickness on the resolution were evaluated in FCRDSA, and FCRDSA images were compared with film substraction with use of this phantom. It has been proven that limitation of resolution of FCRDSA was 5 % 1 mm and about 1/4 dose exposure compared with conventional film exposure was clinically acceptable. Dye dilution method was useful to determine a program of IVDSA with imaging plate. It has been proven that time to appearance and time to peak of time-concentration curve of dye dilution method closely correlate to time to appropriate image of DSA in the neck, the chest, and the abdomen. 106 cases of IVDSA and 130 cases of IADSA using FCR in Tohoku University Hospital from January through December 1984 were analized. 90 % of ...

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The accuracy is investigated of both lymphangiography and CT in detecting lymph nodes metastases in 59 patients evaluated preoperatively and subsequently submitted to surgery with selective/systemic pelvic and paraaortic lymphadenectomy. CT accuracy was also investigated in 46 patients with a clinically suspected relapse of ovarian cancer (verified by means of clinical and/or CT follow-up in 36 patients, by laparotomy in 7, by fine-needle biopsy in 1 and by necroscopy in the last 2). In the first group (previously untreated patients) the overall results in the pelvis were, respectively, for lymphangiography and CT: 94.9% vs 89.8% accuracy, 86.6% vs 60% sensitivity, 97.7% vs 100% specificity, and 92.8% vs 100%, 95.5% vs 88% positive and negative predictive values. In the paraaortic region the results were: 89.1% vs 86.5% accuracy, 73.3% vs 66.6% sensitivity, 100% specificity for both techniques, 100% positive predictive value, and 84.6% vs 81.5% negative predictive value. In the second ...

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In this article is reviewed the role of Computed Tomography (CT) in thoracic complications following ortho topic liver transplantation (OLT). In a post-OLT population of 567 patients transplanted in the Italian institutions, 100 patients (17.6%) were examined with chest CT. It was reviewed data relative to the total number of examinations, clinical and/or radiographic indications, the CT technique-i.e., conventional (with (out) intravenous, i.v., contrast material) or high-resolution (HRCT). It also reviewed the radiologic patterns and their correlation with the other clinical, bronchoscopic and/or laboratory results. Of 152 chest CT examinations, 45 (29.6%) were performed because of clinical indications, 31 (20.4%) because of a radiographic abnormality, 64 (42.1%) because of clinical and radiographic abnormality, 64 (42.1%) because of clinical and radiographic indications, while in 12 cases (7.9%) the reasons were unknown; 133/152 (87.5%) examinations had been performed with ...

International Nuclear Information System (INIS)

The transposition of the great arteries afters to an abnormal connection and relation of the great arteries in which the aorta arises from the morphologic right ventricle and the pulmonary artery from the morphologic left ventricle, while the malposition of the great arteries indicates an abnormal relationship between the great arteries in which the great arteries are not transposed across the ventricular septum but they are malposed, as is seen in double outlet right ventricle, double outlet left ventricle and single ventricles. Transpositions and malpositions of the great arteries are understood as a spectrum of malformation caused by abnormal conal development and can be included in the common category of 'conotruncal malpositions'. Authors analized 32 cases of transpositions and malpositions of the great arteries in which cineangiocardiographies were done at the Department of Radiology, Seoul National University Hospital in recent 17 months, with specific references to the ...

Energy Technology Data Exchange (ETDEWEB)

Gastric stromal tumors are an ill-defined group of lesions arising from muscle wall cells and characterized by extremely variable biological patterns. Thanks to modern immunohistochemical and ultrastructural techniques, four main classes of these lesions have been identified, namely: (1) tumors with differentiation toward smooth muscle cells; (2) tumors with differentiation toward neural elements; (3) tumors with differentiation toward neural elements; (3) tumors with dual differentiation toward either cell type. It was investigated the yield of CT in diagnosing and characterizing gastric stromal tumors. It was retrospectively reviewed the CT findings of 38 patients (15 men and 23 women; mean age 51 years) with pathologically proven gastric stromal tumors, namely 31 of myoid origin, 4 of neural origin, 2 with both muscle and neural differentiation, 1 lacking differentiation with either cell type. The myoid tumors involved gastric fundus in 9/13 and 5/7 benign lesions and lesions with ...

Energy Technology Data Exchange (ETDEWEB)

In this issue it has been investigated the yield of Helical CT in the study of lung vessels, the incidence of the angiogram sign and its actual value. July 1997 to December 1998, were studied 30 cases of pulmonary collapse of different origin. It was found 15 cases of passive collapse (10 from pleural effusion, 2 from diaphragmatic compression, 2 from traumatic pneumothorax, and 1 from isthmic aortic aneurysm), 12 cases of obstructive collapse (9 from bronchogenic carcinoma, 1 from mucoid obstruction, 1 from ilar lymphadenopathy, and 1 from mediastinal cancer), 2 cases of adhesive collapse and 1 case of round atelectasis. All the examinations were performed with the Helical technique during nonionic iodinated contrast agent injection (bolus, 300-350 mg/mL); it was used an automatic injector set at 2-3 mL/s. It was studied the images for the angiogram sign, that is hyperdense bands, usually longer than 2 cm, through the collapsed lung, which correspond to normal ...

Energy Technology Data Exchange (ETDEWEB)

In this article is reviewed the role of Computed Tomography (CT) in thoracic complications following ortho topic liver transplantation (OLT). In a post-OLT population of 567 patients transplanted in the Italian institutions, 100 patients (17.6%) were examined with chest CT. It was reviewed data relative to the total number of examinations, clinical and/or radiographic indications, the CT technique-i.e., conventional (with (out) intravenous, i.v., contrast material) or high-resolution (HRCT). It also reviewed the radiologic patterns and their correlation with the other clinical, bronchoscopic and/or laboratory results. Of 152 chest CT examinations, 45 (29.6%) were performed because of clinical indications, 31 (20.4%) because of a radiographic abnormality, 64 (42.1%) because of clinical and radiographic abnormality, 64 (42.1%) because of clinical and radiographic indications, while in 12 cases (7.9%) the reasons were unknown; 133/152 (87.5%) examinations had been performed with ...