Radiological research activity 1998–2007: relationship to gross domestic product, health expenditure and public expenditure on education

Objective The purpose of this study was to evaluate the relationship of the radiological research activity from 1998 to 2007 to the gross domestic product (GDP), health expenditure and public expenditure on education. Methods The population-adjusted research activity determined by the number of articles published, the cumulative impact factor (IF) and the cumulative IF per capita were correlated with per capita values of the GDP, health expenditure and public education expenditure. Linear regression analysis and multiple regression analysis were used for statistical analysis. Results The cumulative IF per capita correlated with the GDP per capita (R = 0.94, P  0.05). Conclusion Radiological research activity demonstrates a close relationship to the GDP, health expenditure and public expenditure on education. The last factor independently predicts research activity

Dual-energy CT with tin filter technology for the discrimination of renal lesion proxies containing blood, protein, and contrast-agent. An experimental phantom study

PURPOSE: To differentiate proxy renal cystic lesions containing protein, blood, iodine contrast or saline solutions using dual-energy CT (DECT) equipped with a new tin filter technology (TFT). MATERIALS AND METHODS: 70 proxies (saline, protein, blood and contrast agent) were placed in unenhanced and contrast-enhanced kidney phantoms. DECT was performed at 80/140 kV with and without tin filtering. Two readers measured the CT attenuation values in all proxies twice. An 80/140 kV ratio was calculated. RESULTS: All intra- and interobserver agreements were excellent (r = 0.93-0.97; p 0.05). The CT attenuation of protein, blood and contrast agent solution differed significantly with tin filtering (p < 0.01-0.05). Significant differences were found between the ratios of protein and blood compared to contrast medium solution (each, p < 0.05) and between the ratios of protein and blood in both phantoms with tin filtering (each, p < 0.05). CONCLUSION: DECT allows discrimination between a proxy renal lesion containing contrast agent and lesions containing protein and blood through their different attenuation at 80 kV and 140 kV. Further discrimination between protein and blood containing proxies is possible when using a tin filter