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Kit for the Preparation of Technetium Tc 99m Oxidronate
Diagnostic – For Intravenous Use
Technescan™ HDP is supplied as a lyophilized powder, packaged under nitrogen in vials for intravenous administration after reconstitution with ADDITIVE-FREE sodium pertechnetate Tc 99m. Each vial contains 3.15 mg oxidronate sodium and 0.258 mg, minimum, stannous chloride (SnCl2•2H2O), 0.297 mg, theoretical, stannous chloride (SnCl2•2H2O) with 0.343 mg, maximum, tin chloride [stannous and stannic] dihydrate as SnCl2•2H2O as active ingredients. In addition, each vial contains 0.84 mg gentisic acid as a stabilizer and 30.0 mg sodium chloride. The pH is adjusted with hydrochloric acid and/or sodium hydroxide. The pH of the reconstituted drug is between 4.0 and 5.5. The contents of the vial are sterile and non-pyrogenic.
The chemical structure of oxidronate sodium is:
This radiopharmaceutical diagnostic agent, when reconstituted with ADDITIVE-FREE sodium pertechnetate Tc 99m forms a complex of unknown structure.
Technetium Tc 99m decays by isomeric transition with a physical half-life of 6.02 hours.1 The principal photon that is useful for detection and imaging is listed in Table 1.
Table 1. Principal Radiation Emission Data1
|Radiation||Mean Percent/ Disintegration||Energy (keV)|
The specific gamma ray constant for Technetium Tc 99m is 0.78 R/mCi-hr at 1 cm. The first half-value thickness of lead (Pb) for Technetium Tc 99m is 0.017 cm. A range of values for the relative attenuation of the radiation emitted by this radionuclide that results from interposition of various thicknesses of Pb is shown in Table 2. For example,
1 Kocher, David C., “Radioactive Decay Data Tables,” DOE/TIC-11026, 108, (1981). the use of 0.25 cm of Pb will decrease the external radiation exposure by a factor of about 1000.
Table 2. Radiation Attenuation by Lead Shielding
|Shield Thickness (Pb) cm||Coefficient of Attenuation|
To correct for physical decay of this radionuclide, the fractions that remain at selected time intervals after the time of calibration are shown in Table 3.
Table 3. Physical Decay Chart: Technetium
|Hours||Fraction Remaining||Hours||Fraction Remaining|
|* Calibration time|
Last reviewed on RxList: 4/13/2017
This monograph has been modified to include the generic and brand name in many instances.
Additional Technescan Information
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