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Purpose: To assess the diagnostic performance of quiescent-interval single-shot magnetic resonance angiography (QISS-MRA) at 3 tesla in diabetic patients with critical limb ischemia (CLI) vs contrast-enhanced MR angiography (CE-MRA) using digital subtraction angiography (DSA) as the standard of reference.Method: Thirty-seven consecutive diabetic patients (mean age 71.8±7.2 years; 30 men) with CLI (Fontaine stage III-IV) underwent QISS-MRA and CE-MRA with calf compression; DSA was the standard. Image quality (5-point Likert-type scale) and stenosis severity (5-point grading) for QISS-MRA and CE-MRA were evaluated by 2 blinded readers in 1147 and 654 vessel segments, respectively. Per-segment and per-region (pelvis, thigh, calf) sensitivity, specificity, positive predictive value, and negative predictive value were calculated.Results: Image quality of QISS-MRA was lower compared with CE-MRA in the pelvic region (p<0.001 in both readers) and thigh region (p=0.033 in reader 1 and p=0.018 in reader 2), whereas in the calf region, the image quality of QISS-MRA was better than CE-MRA (p=0.009 in reader 1 and p=0.001 in reader 2). In segment-based analyses, there was no difference between QISS-MRA and CE-MRA in sensitivity [89.5% vs 90.3% in reader 1 (p=0.774) and 87.6% vs 90.6% in reader 2 (p=0.266)] or specificity [94.2% vs 92.9% in reader 1 (p=0.513) and 92.9% vs 92.9% in reader 2 (p>0.999)]. In region-based analyses, QISS-MRA and CE-MRA yielded similar sensitivity and specificity in all areas but the pelvic region for reader 2 (specificity 95.5% vs 84.8%, p=0.041).Conclusion: QISS-MRA performed very well in diabetic patients with CLI and was a good alternative for patients with contraindications to CE-MRA. [ABSTRACT FROM AUTHOR]

Background: The purpose of this study was to evaluate the feasibility, safety and efficacy of endovascular treatment of large or giant intracranial aneurysms with the Willis covered stent. Methods: Nineteen patients, each with a large or giant intracranial aneurysm, were treated with the Willis covered stent. Of these 19 aneurysms, 6 were giant and 13 were large; 18 were located in the cranial internal carotid artery and 1 in the vertebral artery. Results of the procedure, technical events and complications were recorded. Clinical and imaging follow-ups were performed at 3 and 6-12 months after the procedure. Results: Placement of Willis covered stent was successful in all patients. Complete aneurysm exclusion was achieved in 13 of the 19 aneurysms immediately after the procedure. No mortality or morbidity developed during the treatment or the follow-up period. During the follow-up period, complete aneurysm exclusion was achieved in 18 of the 19 patients; 11 aneurysms were totally involuted, 3 decreased to 25% of the original diameter, 4 decreased to 50% and 1 remained unchanged. Nine patients experienced full recovery, 9 improved and 1 was unchanged. No obvious in-stent stenosis was noted. Conclusions: Endovascular treatment of large or giant intracranial aneurysm with the Willis covered stent is feasible, safe and efficacious in selected cases. Endoleak is a frequent issue after initial covered stent placement, but can be eliminated or dramatically reduced to minimal endoleak by additional covered stent placement and/or balloon reinflation. Minor endoleak is likely to spontaneously resolve over time. Copyright © 2010 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

6061 aluminum alloy has many advantages, and soldering is the most attractive joining method for 6061 aluminum alloy. In order to expand application of 6061 aluminum alloy, a novel 63Sn-29.2Pb-6Zn-1Ag-0.38Cu-0.42Bi solder alloy was prepared. The melting characteristic and microstructure of the solder were analyzed by differential scanning calorimetry and scanning electron microscope. Its spreading on the 6061 aluminum alloy was also studied. The results show that its melting temperature range is 456.34-463.68 K, and the temperature interval between the solidus and the liquidus is 6.34 K. The solder on 6061 aluminum alloy had better wetting characteristics. A precursor film appears ahead of the spreading droplet. The microstructure at the interface between the solder and the 6061 aluminum alloy was analyzed. It was clear that the intermetallic compound, Ag2Al phase, was formed at the interface between the solder and the 6061 aluminum alloy. [ABSTRACT FROM AUTHOR]