Nuclear medicine questions Thallium 201 method of decay and energy verified answer Thallium 201 decays by electron capture with gamma emissions 135 and 167 kiloelectron volts but the majority of imaging is achieved with it s daughter mercury 201 xrays of about 80kev Stannous chloride verified answer A reducing agent which changes the valence state of Technetium in pertechnetate It has no effect on the amount of aluminum ions or the radiation dose Iodine 131 t 1 2 verified answer 8 06 days Effective half life formula verified answer Effective half life is equal to the product of physical times biological divided by the sum of physical and biological Physical half life definition verified answer The time necessary for the activity be reduced to one half its current activity Biologic half life definition verified answer The time it takes for the body to eliminate half the compound administered Finding activity with decay factor verified answer Activity at time t equals the original activity multiplied by the decay factor which is always less than one Creation of Technetium 99 sulfur colloid verified answer Following the addition of pertechnetate sulfur colloid is heated in a shielded boiling water bath During the time the Technetium 99 is incorporated into the sulfur colloid particles Aluminum ions in Technetium 99 eluate what type of impurity verified answer Chemical impurity Must be less than 10 micrograms aluminum per milliliter of eluate May result in reduced imaging quality due to poor labeling Molybdenum 99 in Technetium 99 what type of impurity verified answer Radionuclidic impurity aka unwanted Radionuclides Limit of point one five microcurie molybdenum per millicurie Technetium at the time dose is administered This impurity results in increased Radiation dose and reduced quality Chromatography kit verified answer The upper portion of the strip is the solvent front and the lower point is the origin where the radiopharmaceutical being tested is introduced The specific kit type determines what this indicates for example particle size impurity etc The purpose of adding EDTA to sulfur colloid when labeling with pertechnetate is verified answer To bind excess aluminum ions thereby preventing aggregates from forming A diphosphonate kit should be use within how many hours after preparation verified answer Four to six hours What is the usual particle size of sulfur colloid verified answer The appropriate particle size of sulfur colloid is point three to one micrometer which allows them to be phagocytized by the kuppfer cells of the liver Which radiopharmaceutical should have the smallest particle size Sulfur colloid albumin colloid human serum albumin or macroaggregated albumin verified answer Human serum albumin making it appropriate for applications like lymphoscintigraphy Effective half life is always shorter than verified answer Either the physical or the biological half life The advantages of albumin colloid over sulfur colloid include verified answer Does not require heating Disadvantages of albumin colloid vs Sulfur colloid verified answer More expensive The recommended dose is comparable for both Using Technetium macro aggregated albumin in the presence of a shunt verified answer Particles will enter the left ventricle and arterial blood resulting in MAA activity in the brain and lungs Pediatric dose may be calculated by verified answer By Weight using Clark s formula according to body surface area or using Talbot s nomogram Clark s formula verified answer the calculation of a pediatric dose by avg adult weight Pediatric dose equals pediatric patients weight in pounds times adult dose divided by average 150 pound adult weight Talbot s nomogram verified answer A calculated table relating body weight to surface area to adjust for a pediatric dose If a specific decay factor is not on a table verified answer It can be calculated by multiplying decay factors that add together to make the elapsed time Lower limits of radiochemical purity differ by radiopharmaceutical but typically are verified answer 90 and above Formula for decay calculation using half life verified answer Activity at time t equals initial activity times eulers number raised to negative point 693 multiplied by time elapsed divided by half life The society of nuclear medicine procedure guidelines recommend how many particles for patients with pulmonary hypertension verified answer 100000 to 200000 Bacteriostatic preservatives should not be used in kits because verified answer They will increase the oxidation products and can affect the radiochemical purity and distribution of the tracer When performing a GI study how can you evaluate the possible appearance of free pertechnetatein the stomach verified answer Imaging the thyroid If there is activity in the thyroid it will confirm free pertechnetate An image of the thyroid should be saved for the radiologist One millicurie is equal to how many megabequerels verified answer One millicurie equals 37 megabequerels Radiation levels in an unrestricted area must be verified answer Less exposure than 2millirem in any one hour 2 millirem equals 0 02 millisievert Caution radiation area verified answer Area where an individual could receive more than 5 millirem in one hour at thirty centimetres from the radiation source Caution high radiation area verified answer Area Where an individual could receive more than one hundred millirem in a hour at thirty centimeters from the radiation source Grave Danger very high radiation area verified answer Area where an individual could receive more than 500rads 5 grays in one hour at one meter from the radiation source Packages must be monitored within verified answer Three hours of receipt during regular working hours or within three hours of department reopening if after hours If there are signs of damage or moisture to a package verified answer Measure exposure rates at the package surface and one meter Notify the NRC and the carrier delivering the package immediately through the radiation safety officer if the exposure rate exceeds 200 milliroentgen per hour at the surface or ten milliroengten per hour at one meter If removable contamination from a package exceeds 22 disintegrations per minute per centimeter squared verified answer Notify the NRC and the carrier through the RSO Radiation safety officer The NRC requires wipe test readings to be recorded in verified answer Disintegrations per minute DPM equals net counts per minute