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PURPOSE: Epilepsies in children are complex diseases. Guidelines are needed on the appropriate use of newer versus older anti-epileptic drugs (AEDs). This paper presents an individual patient-sampling model to assess the cost-effectiveness of using newer AEDs as add-on therapy in line with UK prescribing guidance. METHODS: Identification of the relevant parameters and treatment pathways for the model were achieved by a systematic review of the literature and discussions with clinical experts. Data were obtained from the literature and supplemented with data elicited from paediatric neurologists. The model considered paediatric patients over the period of childhood from the age of diagnosis to 18 years. RESULTS: The results suggest that the older and newer AEDs are similar in terms of drug retention rates and the average time in 'good' treatment outcomes. In terms of cost, the results indicate a consistent increase in cost (compared to older AEDs) when all of the newer AEDs are considered. The decision analysis results indicate that there are no important health benefits from the use of newer AEDs when used as add-on therapy. However, the analysis also reveals that the uncertainties in the model are greater than the differences between the drug strategies. CONCLUSIONS: To develop guidelines on the appropriate use of newer AEDs, better information is required from randomised controlled trials as there is insufficient data available in the public domain to accurately estimate the nature of the trade off between older versus newer AEDs. 相似文献
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Short-Ti inversion-recovery pulse sequence: analysis and initial experience in cancer imaging 总被引:2,自引:0,他引:2
Inversion recovery (IR), commonly considered a pulse sequence capable of producing T1-weighted images with excellent display of normal anatomy, is versatile: The null point and peak time provide a useful, succinct summary of the properties of IR and its capacity for producing both T1- and T2-weighted images. Shortening of the inversion time (TI) and creation of a short-TI inversion-recovery (STIR) pulse sequence increases sensitivity to malignancy and other abnormalities by making the effects of prolonged T1 and T2 on signal intensity additive and by nulling the signal from fat. The authors examined over 300 patients with various malignancies and compared STIR images with T1- and T2-weighted images obtained at 0.5 T. In 43 cases, signal-difference-to-noise ratios (SD/Ns) were calculated between tumor, fat, and muscle. In general, STIR images demonstrated tumor as a conspicuously high-intensity area in a background of muted, discernible anatomic detail. The good contrast achieved with STIR sequences between tumor and fat (SD/N = 18.1) and tumor and muscle (SD/N = 12.9) consolidated into a single image the information contained separately on T1- and T2-weighted images, which facilitates efficient detection and localization of malignancy. 相似文献