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41.
42.

Introduction  

The objective of this study was to explore the volumetric alterations of dural sinuses in patients with idiopathic intracranial hypertension (IIH).  相似文献   
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To evaluate the effect of age, gender and cardiovascular risk factors on vessel wall inflammation and the calcified plaque burden in different vascular beds as assessed by PET/CT. 315 patients (mean age: 57.8 years, 123 male and 192 female) who underwent whole body 18F-FDG PET/CT examinations were included in the study. Blood pool-corrected standardised uptake value (TBR) and the calcified plaque score (CPS, grade 0–4) were determined in the thoracic and abdominal aorta, both common carotid and both iliac arteries. The following cardiovascular risk factors were documented: Age ≥65 years (n = 114), male gender (n = 123), diabetes (n = 15), hyperlipidemia (n = 62), hypertension (n = 76), body mass index (BMI) ≥ 30 (n = 38), current smoker (n = 32). Effects of risk factors on TBR and CPS in different arterial beds were assessed using multivariate regression analysis. In the thoracic aorta TBR was independently associated with age ≥65 years and male gender, CPS was independently associated with age ≥65 years, male gender, hypertension and diabetes. In the abdominal aorta, TBR was independently associated with age ≥65 years and male gender, CPS with age ≥65 years, diabetes and smoking. Independent associations in the carotid arteries were found for age ≥65 years, male gender and BMI ≥ 30 in TBR and for age ≥65 and diabetes in CPS. In the iliac arteries, TBR was independently associated with age ≥65 and CPS with age ≥65, male gender, hypertension, diabetes and smoking. Findings of this PET/CT study demonstrate that the impact of cardiovascular risk factors on vessel wall inflammation and calcified plaque burden differs across vascular territories. Overall, CPS was more closely associated with cardiovascular risk factors compared to TBR.  相似文献   
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PURPOSE: To compare conspicuity of zones of ablation on nonenhanced, gadopentetate dimeglumine-(Gd-DTPA) and ferucarbotran-(SPIO)-enhanced magnetic resonance (MR) images. MATERIALS AND METHODS: In all, 33 radiofrequency ablations (RFA) were performed in 17 healthy porcine livers at 1.5T MR imaging 1 day and 2 and 4 weeks after RFA: T2-weighted (w) ultra turbo spin echo (UTSE), proton density (PD)-w UTSE, T1-w gradient echo (GRE) pre- and 5 minutes postcontrast administration, dynamic T1-w GRE during Gd-DTPA (Magnevist) or SPIO (Resovist) administration, T2-w UTSE, and PD-w UTSE sequences 10 minutes after SPIO administration. Regions of interest (ROIs) for contrast-to-noise ratio (CNR) and signal-to-noise ratio (SNR) were drawn in consensus by two radiologists. RESULTS: PD-w SPIO-enhanced images (23.5 +/- 5.5) showed higher liver-to-lesion CNR than T1-w GRE Gd-DTPA-enhanced images (13.5 +/- 6.1) 1 day after RFA (P < or = 0.05). At all other timepoints, liver-to-lesion CNR of PD-w and T2-w SPIO-enhanced images did not differ significantly from T1-w GRE Gd-DTPA-enhanced images (P > or = 0.05). Nonenhanced T2-w images revealed lower liver-to-lesion CNR (7.0 +/- 7.5/6.5 +/- 5.9/6.8 +/- 5.0, 1 day/2 weeks/4 weeks, respectively) than T2-w SPIO-enhanced (17.4 +/- 4.8/15.3 +/- 4.5/14.2 +/- 5.7), PD-w SPIO-enhanced (23.5 +/- 5.5/16.9 +/- 3.6, 1 day/2 weeks), and T1-w Gd-DTPA-enhanced (15.3 +/- 3.6/12.7 +/- 3.5, 2/4 weeks) images (P < or = 0.05). Liver-to-lesion CNR of SPIO-enhanced dynamic T1-w GRE images after 30, 80, 150, and 240 seconds did not change significantly over time (P > or = 0.05). CONCLUSION: One day after RFA lesion conspicuity on PD-w ferucarbotran-enhanced images is better than on T1-w GRE Gd-DTPA-enhanced images. At all other timepoints, ferucarbotran is not superior to gadolinium. Ferucarbotran- and gadolinium-enhanced images improve lesion conspicuity compared with nonenhanced T2-w images at all timepoints.  相似文献   
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BACKGROUND: Right heart dysfunction is a major cause for early morbidity and mortality after heart transplantation. Experiments were designed to evaluate the influence of the calcium-desensitizing drug 2,3-butanedione 2-monoxime (BDM) on right heart function in a porcine model of heart transplantation. METHODS: Donor hearts of domestic pigs were arrested with BDM in Krebs solution (n = 7) and with BDM in Bretschneider's histidine-tryptophan-ketoglutarate (HTK) solution (n = 6). There were 2 control groups: University of Wisconsin (UW, n = 6) and HTK (n = 6). An isovolumic model was used in which the right ventricular volume was precisely controlled in vivo with an intracavitary high-compliance balloon. After 4 hours of ischemia, hearts were transplanted into recipients. After 1 and 2 hours of reperfusion, the right ventricular balloon volume was increased in 10-mL increments until right ventricular failure occurred and the developed pressures were recorded. RESULTS: Maximal right ventricular developed pressures were significantly different after 2 hours of reperfusion (UW: 35 +/- 13 mm Hg; HTK: 47 +/- 8 mm Hg; Krebs+BDM: 49 +/- 9 mm Hg; HTK+BDM: 50 +/- 6 mm Hg; P =.04). Hearts subjected to BDM could be loaded with a significantly increased volume after 1 hour and after 2 hours (UW: 57 +/- 10 mL vs HTK: 43 +/- 8 mL vs Krebs+BDM: 70 +/- 10 mL vs HTK+BDM: 67 +/- 15 mL; P =.002). Postischemic right ventricular enddiastolic compliance was significantly increased in groups treated with BDM after 1 hour (P =.02) and after 2 hours (P =.039). CONCLUSIONS: The drug BDM significantly improves right ventricular function in a heart transplantation model. The increase in volume load and developed right ventricular pressure achieved by BDM application would translate into a decreased risk of right ventricular failure after clinical transplantation.  相似文献   
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Introduction  

The quality of surgical treatment of intracranial aneurysms is determined by complete aneurysm occlusion and restoration of flow in the parent, branching and perforating vessels. In postoperative digital subtraction angiography (DSA), unexpected aneurysm residuals and vessel occlusions are frequently detected. Here, the value of two nearly noninvasive and cost-effective techniques for intraoperative flow evaluation (near-infrared indocyanine green video angiography (ICG-VA) and microvascular Doppler sonography (mDs)) is investigated in a prospective study.  相似文献   
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