Presentation on theme: "Hot Lab 2 Problem Solving"— Presentation transcript:
1Hot Lab 2 Problem Solving 12Hot Lab 2Problem Solving
2Q 1If a bone scan has been ordered on a 5-year-old girl, and the physician prescribes 60% of the adult dose to be given, how many mCi should be administered?
3Q 2If the biological half-life of an isotope is6 hours, and the physical half-life is 12hrs,what is the effective half-life?
4Q 3A vial containing 99mTc is assayed at 9:00 a.m. And contains 255 mCi.To calculate the remaining activity at 3:00 pm
5Q 4If a kit contains 140 mCi of 99mTc in 20 ml, how much volume must be withdrawn to obtain a dose of 5 mCi?
6Q 5If a radiopharmaceutical is spilled on the floor, the firstpriority is to:a. contact the Radiation Safety Officerb. pour a chelating solution over the area of the spillc. cover the area with absorbent paper and restrict accessaround itd. call the housekeeping department to arrangefor cleaning
7Q 6A vial of technetium eluate contains 50 mCi/ml. If 4 ml are withdrawn and added to a diphosphonate kit containing 16 ml of solution,what volume would then need to be withdrawn to prepare a 20 mCi dose at that moment?
8Half value layer HVLThe thickness of any given material where 50% of the incident energy has been attenuated is know as the half-value layer (HVL).The HVL is expressed in units of distance (mm or cm) of thickness of the shielding material (usually lead).
10The HVL is often used in nuclear medicine simply because it is easier to remember values and perform simple calculations for shielding.It can be seen that if the thickness of one HVL is known, it is possible to quickly determine how much material is needed to reduce the intensity to less than 1%.
11Half-lives of radiopharmaceuticals The physical half-life (Tp) of a radiopharmaceutical is the amount of time necessary for the radioactive atoms to decay to one half their original number.Each radionuclide is characterized by a specific half-life that is a physical constant