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CT angiography (CTA) plays an important role in diagnosing coronary arterial disease. Delay time and density of the coronary arteries related with patient-specific factors are essential for getting an optimal CTA image.

BackgroundSmall peripheral lung nodules detected on computed tomography (CT) scans are often difficult to find during thoracoscopic resection, and the present localizing techniques are inefficient or impractical.PurposeTo evaluate a novel marking procedure for small peripheral pulmonary nodules using an embolization coil.Material and MethodsPatients with small peripheral pulmonary nodules underwent preoperative CT-guided nodule localization using an embolization coil and then resection by fluoroscopically-guided video-assisted thoracoscopic surgery (VATS; group A, n = 22), or, underwent conventional VATS without prior location procedures (group B, n = 16). Comparisons were made between group A and group B concerning operative time, hospitalization, postoperative drainage, and complications. Histopathological diagnoses were made immediately after resection of pulmonary nodules.ResultsAll CT-guided embolization coil fixations were successful. No patient in group A and eight (50%) in group B required conversion to open thoracotomy (P < 0.0001). No severe complications occurred in either group. Compared with group B, group A had a significantly shorter mean operative time and hospitalization, and less postoperative drainage.ConclusionPreoperative localization of small peripheral pulmonary nodules using CT-guided embolization coil insertion and subsequent fluoroscopically-guided VATS resection is safer and more effective than conventional VATS.

BackgroundUltrasound can be used for the diagnosis of elbow injuries in infants and toddlers. However, ultrasound is highly operator-dependent and accurate ultrasound examinations require a complete understanding of the complex anatomy of the elbow joint.PurposeTo report the normal ultrasound anatomy of the elbow, particularly of the humeroulnar joint, in infants and toddlers.Material and MethodThirty subjects aged <3 years with no history of elbow injuries underwent ultrasound examinations of the elbow joint from six directions: (i) lateral to the humeroradial joint; (ii) anterior to the humeroradial joint; (iii) posterior to the humeroradial joint; (iv) medial to the humeroulnar joint; (v) anterior to the humeroulnar joint; and (vi) posterior to the humeroulnar joint.ResultsThe appearance of the humeroradial joint observed from three directions was similar and resembled a pair of double fists (“double-breast sign”). The appearance of the humeroulnar joint observed from three directions was different, which is related to the irregular morphology of the medial sides of the humerus and ulna. Anteroposteriorly, the coronoid and olecranon epiphyses and coronoid fossa appear anteriorly and the olecranon and trochlear epiphyses and olecranon fossa appear posteriorly, resembling a “check-mark sign”. The medial epicondyle, cubital tunnel and distal humerus appear together (“double-hump sign”). The “anterior hump” is the medial epicondyle and is always higher than the “posterior hump”, which is the bony protrusion on the articular surface of the distal humerus. The ultrasound signal of cortical bone in the metaphysis of the distal humerus is continuous with that of the epiphysis of the medial epicondyle.ConclusionUltrasound is useful for the diagnosis of elbow injuries in infants and toddlers.

AbstractA series of SnO2-Al2O3composite metal oxide supports with different Sn/Al atomic ratios were synthesized with co-precipitation method and used as supports for Pd to prepare catalysts for CO oxidation. The samples were characterized by N2adsorption-desorption, CO adsorption-desorption, X-ray Powder Diffraction (XRD), H2temperature programmed reduction (H2TPR), and X-ray photoelectron spectroscopy (XPS) techniques. It was found that Al3+can be introduced into the crystalline lattice of tetragonal rutile SnO2to effectively form solid solution structure. As a consequence, SnO2-Al2O3binary supports with significantly improved thermal stability, enlarged surface areas, enhanced texture structure and containing more active surface oxygen species can be obtained. SnAl73, a support with a Sn/Al atomic ratio of 7/3, was found to be the best support in this study due to its certain large surface area and the presence of suitable amount of reducible oxygen species. With this support, the two major reasons accounting for the activity, that is, Pd dispersion and strong metal support interaction (SMSI) between Pd and the support, is believed to be tuned optimally. Water vapor has reversible effect on the CO oxidation activity of Pd/SnAl73 catalyst, but which is mitigated evidently by the presence of SnO2. In addition, no any permanent deactivation occurs to Pd/SnAl73 catalyst during a 60 hours' test in the presence or absence of water vapor, indicating this optimized SnO2-Al2O3support has a strong potential to be applied in some practical processes for exhaust clean. In summary, SnO2-Al2O3composite metal oxides with suitable Sn/Al atomic ratios are better supports than individual Al2O3and SnO2, on which less amount of Pd could be used to achieve supported Pd catalysts with rival performance.

The adsorption of water in the mesoporous silica material with cylindrical pores of uniform diameter, Controlled Pore Glass 10-75 (CPG), was studied by 1H-MAS solid state NMR spectroscopy. From the NMR spectra it is evident that inside the mesopores of the silica different water environments exist, which are characterized by their individual chemical shift. All observed hydrogen atoms are either surface –SiOH groups or hydrogen bonded water molecules. It is found that there exist some stronger bound water molecules on the surface which are not removable even by heating at a vacuum pump. As a tentative assignment these water molecules are attributed to surface defects or inaccessible cavities in the CPG 10-75. At intermediate water filling levels, the principal signal is a single NMR line with continuously varying chemical shift. This finding is interpreted as the result of a radial water filling mechanism. That is, the filling of the pore grows from the pore surface towards the pore axis. Finally it is shown that water is a sensor for surface and structural inhomogeneity and that a coexistence of inner pore and outer bulk water exists in the system.

BackgroundApplication of dual-energy CT in characterization of adrenal nodules has not been well evaluated.PurposeTo evaluate the ability of dual-energy CT scan to differentiate an adrenal adenoma from a metastasis.Material and MethodsFifty-five patients presenting 63 adrenal nodules underwent dual-energy CT scan at tube voltages of 80 kVp and 140 kVp. Mean attenuation values were measured for every nodule at 80/140 kVp and at 40/100 keV. Mean attenuation value changes between 140 kVp and 80 kVp (MAVC140–80kVp) and mean attenuation value changes between 100 keV and 40 keV (MAVC100–40keV) were calculated.ResultsOf the 63 adrenal nodules available for analyses, 42 nodules were classified as adenoma (26 lipid-rich and 16 lipid-poor) and 21 were classified as metastases. MAVC140–80kVpand MAVC100–40keVof all adenomas (including lipid-poor and lipid-rich) were significantly higher than metastases (P < 0.001). According to receiver-operating characteristic (ROC) curve analyses, areas under the ROC curve of MAVC140–80kVpand MAVC100–40keVfor diagnosing adrenal adenomas were both of 0.964. When the cut-off points were set at 2.42 HU and 6.95 HU for MAVC140–80kVpand MAVC100–40keV, the two parameters both had a sensitivity of 78.6% and a specificity of 100% in adenoma diagnosis.ConclusionUnique energy spectrum information provided by dual-energy CT scan displays a high capacity to distinguish adrenal adenoma from metastasis.

BackgroundBreast cancer is the most common cancer in women worldwide. However, it remains a difficult diagnosis problem to differentiate between benign and malignant breast lesions, especially in small early breast lesions.PurposeTo assess the diagnostic value of diffusion-weighted imaging (DWI) combined with T2-weighted imaging (T2WI) for small breast cancer characterization.Material and MethodsFifty-eight patients (65 lesions) with a lesion <2 cm in diameter underwent 3.0 Tesla breast magnetic resonance imaging (MRI) including DWI and histological analysis. Three observers with varying experience levels reviewed MRI. The probability of breast cancer in each lesion on MR images was recorded with a 5-point scale. Areas under the receiver-operating characteristic curve (AUCs) were compared by using the Z test; sensitivity and specificity were determined with the Z test after adjusting for data clustering.ResultsAUC of T2WI and DWI (Observer 1, 0.95; Observer 2, 0.91; Observer 3, 0.83) was greater than that of T2WI (Observer 1, 0.80; Observer 2, 0.74; Observer 3, 0.70) for all observers (P < 0.0001 in all comparisons). Sensitivity of T2WI and DWI (Observer 1, 90%; Observer 2, 93%; and Observer 3, 86%) was greater than that of T2WI alone (Observer 1, 76%; Observer 2, 83%; Observer 3, 79%) for all observers (P < 0.0001 in all comparisons). Specificity of T2WI and DWI was greater than that of T2WI alone for observer 1 (89% vs. 72%, P < 0.01) and observer 2 (94% vs. 78%, P < 0.001).ConclusionDWI combined with T2WI can improve the diagnostic performance of MRI in small breast cancer characterization. It should be considered selectively in the preoperative evaluation of patients with small lesions of the breast.