Essay About Average Background Radiation Dose And Hrif Tc99M

Nuclear Medicine Pearls
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5 Gauss line = 5 mT = 0.005 T Average background radiation dose to US citizen = 300 mremConsider therapeutic abortion if dose to fetus > 10 rad (0.1 Gy)To categorize area as restricted from general public, average dose rate > 2 mrem/hrIf Tc99m is given to lactating female, cease breast-feeding for 4 daysTerminate breast-feeding altogether after administration of I131 or Ga67Test for Mo99 contamination in Tc99m samples by using a dose calibratorUse thin layer chromatography to test for free Tc in Tc99mUse colorimeter to test for Al in Tc99m MDPWhite label I < 0.5 mremYellow < 50 mrem/hr – AND – not > 1 mrem/hr @ 1 meterYellow III > 50 mrem/hr – OR – > 1 mrem/hr @ 1 meterMaximum allowable exposure to family members of patients with I131 = 5 mSvRisk for congenital defects from radiation to general population significantly increases > 15 rad (150 mGy)Radiotherapy dose must be > 20% to report to NRCA well counter does not use a gas-filled chamber to detect radiation levelsMo99/Tc99m generator operates on principle of transient equilibrium and is state where daughter radionuclide is short than that of parent radionuclideIn secular equilibrium, radioactive daughter’s decay rate is balanced by own decay rateRisk of congenital defects to fetus significantly increases > 100 mGyAnnual occupational dose equivalent limit to single organ in radiation worker = 50000 mrem (500 mSv).NaI123 has t1/2 = 13.2 hrTheraspheres used for unresectable HCC, SIR-Spheres used for liver metsDose calibrator QC –        Geometry: performed at installation        Constancy: daily (“constantly”)        Linearity: quarterly        Accuracy: annually