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CardioVascular and Interventional Radiology - Purpose Bronchopleural fistula is a rare but serious complication of lung ablation, as it is difficult to treat and is associated with a high mortality...  相似文献   
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ObjectiveTo assess the performance of diffusion tensor imaging (DTI) for the diagnosis of cervical spondylotic myelopathy (CSM) in patients with deformed spinal cord but otherwise unremarkable conventional magnetic resonance imaging (MRI) findings.ResultsThe MD, LD, and RD cut-off values were 1.079 × 10-3, 1.719 × 10-3, and 0.749 × 10-3 mm2/sec, respectively, and that of FA was 0.475. Sensitivity, specificity, positive predictive value and negative predictive value were: 100 (4/4), 44.8 (13/29), 20 (4/20), and 100 (13/13) for MD; 100 (4/4), 27.6 (8/29), 16 (4/25), and 100 (8/8) for FA; 100 (4/4), 58.6 (17/29), 25 (4/16), and 100 (17/17) for MD∩FA; 100 (4/4), 68.9 (20/29), 30.8 (4/13), and 100 (20/20) for LD∩FA; and 75 (3/4), 68.9 (20/29), 25 (3/12), and 95.2 (20/21) for RD∩FA in percentage value. Diagnostic performance comparisons revealed significant differences only in specificity between FA and MD∩FA (p = 0.003), FA and LD∩FA (p < 0.001), FA and RD∩FA (p < 0.001), MD and LD∩FA (p = 0.024) and MD and RD∩FA (p = 0.024).ConclusionFractional anisotropy combined with MD, RD, or LD is expected to be more useful than FA and MD for diagnosing CSM in patients who show deformed spinal cords without signal changes on MRI.  相似文献   
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Objective

The aims of this study were to compare opening and closing angles of normally functioning mechanical aortic valves measured on dual-source computed tomography (CT) with the manufacturers'' values and to compare CT-measured opening angles according to valve function.

Materials and Methods

A total of 140 patients with 10 different types of mechanical aortic valves, who underwent dual-source cardiac CT, were included. Opening and closing angles were measured on CT images. Agreement between angles in normally functioning valves and the manufacturer values was assessed using the interclass coefficient and the Bland-Altman method. CT-measured opening angles were compared between normal functioning valves and suspected dysfunctioning valves.

Results

The CT-measured opening angles of normally functioning valves and manufacturers'' values showed excellent agreement for seven valve types (intraclass coefficient [ICC], 0.977; 95% confidence interval [CI], 0.962-0.987). The mean differences in opening angles between the CT measurements and the manufacturers'' values were 1.2° in seven types of valves, 11.0° in On-X valves, and 15.5° in ATS valves. The manufacturers'' closing angles and those measured by CT showed excellent agreement for all valve types (ICC, 0.953; 95% CI, 0.920-0.972). Among valves with suspected dysfunction, those with limitation of motion (LOM) and an increased pressure gradient (PG) had smaller opening angles than those with LOM only (p < 0.05).

Conclusion

Dual-source cardiac CT accurately measures opening and closing angles in most types of mechanical aortic valves, compared with the manufacturers'' values. Opening angles on CT differ according to the type of valve dysfunction and a decreased opening angle may suggest an elevated PG.  相似文献   
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The total cost of hematopoietic stem cell transplantation (HSCT) as well as the financial impact of HSCT on the house holds of patients have been elusive. Between 2005 and 2012, we analyzed 191 HSCT in adult patients with leukemia with reduced‐intensity conditioning (RIC) regimen (n = 79) and with myeloablative conditioning (MAC) regimen (n = 112). The direct medical costs were calculated from healthcare claims obtained from the Seoul National University Hospital, and the direct non‐medical and the indirect costs were calculated from national statistics. The mean direct medical cost was $55 039, direct non‐medical cost was $6394, and indirect cost was $7503 from transplantation to one yr after transplantation in the RIC group and $72 916, $6993, and $9057 in the MAC group, respectively, based on the exchange rate of Korean won 1060 = US$1. The total costs for one yr were $68 938 and $88 967, constituting for 273% and 357% of the per capita income, respectively. The total costs, direct medical costs, and indirect costs showed statistically significant differences (p = 0.006, p = 0.007, and p = 0.017). No significant differences were found for leukemia‐free survival and overall survival. RIC‐HSCT provides lower costs within the first year of transplantation with comparable long‐term clinical outcomes.  相似文献   
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