sodium-pertechnetate-tc-99m and Phlebitis

Periphlebitis retinae (PR) in multiple sclerosis (MS) is seen as transitory infiltrations around veins in the otherwise normal retina. Cellular infiltrations have been found around veins in the central nervous system (CNS), where it has been suggested that they are the first event in plaque formation. Technetium brain scans are usually normal in MS patients, but transitory abnormal scans of the cerebrum have been found in MS patients during acute attack or exacerbation. In order to test the hypothesis that active PR is a sign of simultaneous disease activity in the CNS, 29 technetium brain scans were carried out on 14 MS patients with active PR and on 15 MS patients without any signs of PR. Significantly more of the patients with active PR, compared with MS patients with previous PR, displayed abnormal brain scans. This indicates that a disruption of the blood brain barrier (BBB) and active PR occur simultaneously in MS.

Topics: Adolescent; Adult; Blood-Brain Barrier; Humans; Middle Aged; Multiple Sclerosis; Phlebitis; Radionuclide Imaging; Retinal Vein; Sodium Pertechnetate Tc 99m; Technetium

Human fibrinogen was labeled with 99m-Technetium. Tin(II)-chloride in citric acid served as reducing agent for the pertechnetate-ion, eluted from a Mo-Tc-generator. Before adding the fibrinogen, the citric acid was always neutralized with sodium hydrogen carbonate. The influences on the quantity of fibrinogen bound 99m-Tc of the relative concentrations of Sn(II), fibrinogen and sodium hydrogen carbonate, of the reaction time and temperature were tested by thin-layer chromatography. The reaction temperature of 28 degrees C showed an optimum of fibrinogen bound 99m-Tc for the reaction time from 1 and 2 hours. With a reaction time of 30 minutes not enough 99m-Tc was bound to fibrinogen, the doubling of the reaction time from 1 to 2 hours showed only an increase of binding of less than 4%. The concentration of Sn(II) with respect to the fibrinogen concentration showed no influence on the quantity of fibrinogen bound 99m-Tc at low Sn(II)-concentrations. At values higher than 34 times of the fibrinogen concentration a decrease of the quantity of bound 99m-Tc was observed. The concentrations of sodium hydrogen carbonate showed no influence on the quantity of fibrinogen bound 99m-Tc but on the clottability of fibrinogen, the pH of the solution must be approximately 7.5. In 3 parallel and independent experiments under optimized conditions (1 hour at 28 degrees C, molar ratio of Sn(II) : fibrinogen = 8.5, pH = 7.5) 89.97 +/- 0.92 % of 99 m-Tc were bound to fibrinogen. Controls of these results by column chromatography showed a binding of 81.08 +/- 1.47 % of 99m-Tc to fibrinogen. The clottability of fibrinogen tested by the method of Clauss (1) was entirely preserved.

Topics: Bicarbonates; Fibrinogen; Hydrogen-Ion Concentration; Isotope Labeling; Phlebitis; Radionuclide Imaging; Sodium Bicarbonate; Sodium Pertechnetate Tc 99m; Technetium; Temperature; Time Factors; Tin; Tin Compounds