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Objectives: We studied age-related changes in T2 relaxation times from the normal maturating human brain under routine clinical MR examination conditions., Materials and Methods: In 70 healthy subjects aged between 3 weeks and 39 years, T2 maps of the brain in which the intensity of each pixel corresponded to T2 relaxation times were generated based on magnetic resonance imaging data collected with a triple spin echo sequence. T2 relaxation times in white matter (WM) and gray matter (GM) were measured in 6 distinctive regions of interest of the T2 maps. The age dependence of the T2 values was mathematically simulated using a biexponential function., Results: T2 values were largest at the age of 3 weeks (maximum: approximately 400 milliseconds for WM and 200 milliseconds for GM) and decreased continuously with increasing age, faster in the first few months and slower thereafter, until values achieved between 95 and 110 milliseconds for WM and 88 and 95 milliseconds for GM in adults. The relationship between T2 values and age could be well simulated using a biexponential function (R > 0.92)., Conclusions: T2 relaxation time correlates well with the progress of brain maturation. The used biexponential function reflects the dynamic development of myelination in newborns and young children as well as the maturation of myelination during adolescence and could be used to develop a "normal" reference for neuroradiological diagnoses.

The results of endoscopic drainage treatment in 69 patients with metastases of the liver have been analyzed for the period from 1982 to 1992. Fifty-five patients had follow-up. Criteria for inclusion were: positive diagnosis of liver metastases, jaundice, and primary origin of tumors distant from the pancreaticobiliary system ("distant" primary). Localisations of metastic obstructions were: hilum of the liver (n = 24), commonbile duct (n = 16), and prepapillary region (n = 15). Treatment was performed by transpapillary applications of one or more (n = 3) pig-tail or Tannenbaum stents. Concentrations of mean serum bilirubin could be reduced from 14.5% to 8.8 mg%, 16 patients reached a normal level (less than 1.0 mg%). The median survival time was 76 days ranging vom 4 to 299 days. The most frequent complication was cholangitis in 29% of the cases with mortality in 6 patients. Patients less than 60 years of age and with obstructions in the mid commonbile duct gained most by this kind of treatment. Results were poor in elderly patients with hilar stenosis. Selected patients with known liver metastases may benefit from endoscopic treatment of jaundice.