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71.
72.
PURPOSE: The Contrast Media Safety Committee (CMSC) of the European Society of Urogenital Radiology (ESUR) has updated its 1999 guidelines on contrast medium-induced nephropathy (CIN). AREAS COVERED: Topics reviewed include the definition of CIN, the choice of contrast medium, the prophylactic measures used to reduce the incidence of CIN, and the management of patients receiving metformin. Key Points ? Definition, risk factors and prevention of contrast medium induced nephropathy are reviewed. ? CIN risk is lower with intravenous than intra-arterial iodinated contrast medium. ? eGFR of 45 ml/min/1.73 m (2) is CIN risk threshold for intravenous contrast medium. ? Hydration with either saline or sodium bicarbonate reduces CIN incidence. ? Patients with eGFR ≥ 60 ml/min/1.73 m (2) receiving contrast medium can continue metformin normally.  相似文献   
73.
PURPOSE OF REVIEW: This review aims to outline recent developments in adrenal imaging and characterization. Controversies in the management of adrenal incidentalomas will be addressed. RECENT FINDINGS: Evaluation of density readings on unenhanced computed tomography and on contrast-enhanced delayed series has tremendously improved the characterization of adrenal masses. Attenuation measurements may, however, vary between different scanner types and may also be influenced by patient factors and the scanning technique. Evaluation of the mean percentage washout for adrenal masses on delayed enhanced computed tomography series is independent of such factors and allows the characterization of adrenal lesions with high sensitivity and specificity. In magnetic resonance imaging, dynamic gadolinium-enhanced and chemical-shift techniques have significantly improved the characterization of adrenal masses. Nuclear medicine studies prove to be useful adjuncts. Controversial reports have been published on the role of positron emission tomography/computed tomography in adrenal imaging. Adrenal venous sampling may allow differentiation of aldosteronoma and idiopathic hyperaldosteronism. SUMMARY: Recent developments in adrenal mass imaging have improved the characterization of adrenal mass lesions. The need for histology sampling of incidentally discovered adrenal masses has been significantly reduced due to the high specificity of these new techniques. Controversies still exist regarding the optimal strategy for hormonal screening of a patient with an incidentally detected adrenal mass.  相似文献   
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Based on the hypothesis that soy food consumption may influence breast tissue activity, we examined its effect on the production of nipple aspirate fluid (NAF), a possible indicator of breast cancer risk. Of 310 premenopausal women screened, 112 (36%) produced at least 10 μL of NAF, the minimum for study participation. In a crossover design, we randomized 96 women to 2 groups who, in reverse order, consumed a high-soy diet with 2 soy servings/d (1 serving = 177 mL soy milk, 126 g tofu, or 23 g soy nuts) and a low-soy diet with <3 servings/wk of soy for 6 mo each separated by a 1-mo washout period. During each diet period, 3 NAF samples were obtained (baseline and 3 and 6 mo) using a FirstCyte Aspirator and 4 urine samples (baseline and 1, 3, and 6 mo) were analyzed for isoflavonoids by liquid chromatography tandem MS. Adherence to the study protocol according to 24-h dietary recalls and urinary isoflavonoid excretion was high. The drop-out rate was 15% (n = 14); 82 women completed the intervention. The 2 groups produced similar mean NAF volumes at baseline (P = 0.95) but differed in age and previous soy intake and in their response to the intervention (P = 0.03). In both groups, NAF volume decreased during the first 3 mo of the high-soy diet period and returned to baseline at 6 mo, but there was no effect of the high-soy diet on NAF volume (P = 0.50 for diet; P-interaction = 0.21 for diet with time). Contrary to an earlier report, soy foods in amounts consumed by Asians did not increase breast tissue activity as assessed by NAF volume.  相似文献   
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This analysis examined type 2 diabetes (T2D) as a predictor of colorectal cancer (CRC) survival within the Multiethnic Cohort Study. Registry linkages in Hawaii and California identified 5,284 incident CRC cases. After exclusion of cases with pre‐existing cancer diagnosis within 1 year and systemic disease, the analytic dataset had 3,913 cases with 1,800 all‐cause and 678 CRC‐specific deaths after a mean follow‐up of 9.3 ± 5.2 years. Among CRC cases, 707 were diagnosed with T2D 8.9 ± 5.3 years before CRC. Cox regression with age as time metric was applied to estimate hazard ratios (HR) and 95% confidence intervals (CI) for T2D status as predictor of CRC‐specific and all‐cause survival while adjusting for known confounders. Overall, CRC‐specific survival was not associated with pre‐existing T2D (HR = 0.84; 95% CI = 0.67–1.07). However, a significant interaction was seen for comorbidity (pinteraction = 0.03) with better survival among those without pre‐existing conditions (HR = 0.49; 95% CI = 0.25–0.96) while no association was seen in patients with comorbid conditions. All‐cause mortality was also not related to pre‐existing T2D (HR = 1.11; 95% CI = 0.98–1.27), but significantly elevated for individuals with T2D reporting comorbid conditions (HR = 1.36; 95% CI = 1.19–1.56). Stratification by T2D duration suggested higher CRC‐specific and all‐cause mortality among participants with a T2D history of ≥10 than <10 years. The findings were consistent across sex and ethnic subgroups. In contrast to previous reports, pre‐existing T2D had no influence on disease‐specific and all‐cause survival among CRC patients. Only participants with additional comorbidity and possibly those with long T2D duration experienced higher mortality related to T2D.  相似文献   
78.

Objectives

Radiofrequency (RF) energy has recently been employed to destroy human tissue in vivo. The purpose of this study was to investigate the safety of this approach in localized carcinoma of the prostate (CaP) and specifically, the predictability of lesions obtained with radiofrequency interstitial tumor ablation (RITA).

Methods

Using RITA, a total of 21 lesions were induced in 10 patients with localized CaP (mean age 70.4 years). RF was delivered transperineally under transrectal ultrasound (TRUS) guidance. All patients underwent endorectal magnetic resonance imaging (MRI) before and after treatment. Radical prostatectomy was performed in all patients 1 to 7 days after RITA. Three of the patients were treated with local anesthesia only. The predictability of the thermal lesion was assessed by correlating the findings of intraoperative TRUS, preand post-RITA endorectal MRI, and the histologic examination of the specimen.

Results

Postoperatively, patients were catheterized for an average of 1.8 days (1 to 3 days). Lesions of 2 × 2 × 2 cm were targeted. Average lesion diameters obtained on MRI were 2.08 ± 0.23 × 2.09 ± 0.36 × 2.28 ± 0.21 cm. Average lesion diameters defined by coagulative necrosis at histologic examination were 2.20 ± 0.23 × 2.10 ± 0.31 × 2.38 ± 0.14 cm. There were no statistically significant differences (P = 0.377) between average lesion volume on MRI (5.37 ± 1.83 cm3) and average lesion volume at histology (5.86 .63 cm3). No complications or adverse events were noted.

Conclusions

In this Phase I study, RITA was shown to be safe and feasible, and to result in lesions that were predictable in size and location. MRI accurately visualized and verified the area of coagulative necrosis as documented at histology. The procedure is technically simple and can even be performed under local anesthesia.  相似文献   
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The purpose of this phase III clinical trial was to compare two different extracellular contrast agents, 1.0 M gadobutrol and 0.5 M gadopentate dimeglumine, for magnetic resonance imaging (MRI) in patients with known or suspected focal renal lesions. Using a multicenter, single-blind, interindividual, randomized study design, both contrast agents were compared in a total of 471 patients regarding their diagnostic accuracy, sensitivity, and specificity to correctly classify focal lesions of the kidney. To test for noninferiority the diagnostic accuracy rates for both contrast agents were compared with CT results based on a blinded reading. The average diagnostic accuracy across the three blinded readers (‘average reader’) was 83.7% for gadobutrol and 87.3% for gadopentate dimeglumine. The increase in accuracy from precontrast to combined precontrast and postcontrast MRI was 8.0% for gadobutrol and 6.9% for gadopentate dimeglumine. Sensitivity of the average reader was 85.2% for gadobutrol and 88.7% for gadopentate dimeglumine. Specificity of the average reader was 82.1% for gadobutrol and 86.1% for gadopentate dimeglumine. In conclusion, this study documents evidence for the noninferiority of a single i.v. bolus injection of 1.0 M gadobutrol compared with 0.5 M gadopentate dimeglumine in the diagnostic assessment of renal lesions with CE-MRI.
Bernd TombachEmail:
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