NUCLEAR MEDICINE
INSTRUMENTATION
Radiation exposure rates are measured by – answer Survey meters
Contamination surveys can be performed with - answerA Geiger Muller counter
A Geiger Muller counter is appropriate for contamination surveys because it -
answerHas a rapid response time and can detect a wide range of exposure rates
A Geiger Muller counter meets the NRC requirement for facilities to have - answerA
survey meter capable of detecting exposure rates from 0.1 millirems per hour to one
hundred millirems per hour
GM counters may be fitted with - answerAn end window probe or a pancake probe
The pancake probe - answerAllows the technologist to survey a larger area
The end window probe - answermust be pointed directly at a source for accurate
detection
Portable ionization chambers are also known as - answerCutie pies
Cutie pies or portable ionization chambers vs Geiger Muller counters - answerGeiger
Muller counters are more sensitive. Cutie pies are more accurate
The cutie pie is more accurate because - answerIt has a longer response time so the
exposure rate is calculated based on more data
The cutie pie is superior in measuring - answerHigh dose rates such as those in patient
doses, especially therapeutic doses
A well counter works by - answerUsing a Thallium activated sodium iodide crystal to
detect low levels of radioactivity
Compared to a gamma camera a well counter is - answerMore efficient
The well counter's sensitivity limits the instruments use because - answerActivities
greater than two microcuries can cause coincidence loss
When too many photons strike the crystal in a well counter - answerCounts are lost
while the instrument is in deadtime
, If the counting rate is very high in a well counter - answerIt may cause perpetual
deadtime paralysis
The well counter is used for - answerWipe tests to detect very low levels of removable
contamination
Well counter use in non imaging studies - answerused to count blood plasma and urine
samples when Standards for blood volume or Schilling tests are diluted to a known
percentage of the original patient dosage
Uptake probe - answerUses a sodium iodide crystal to quantitate activity within a
patient. May be connected to the spectrometer used by the well counter
The uptake probe is not as sensitive as the well counter because of - answerDetector to
source geometry
Uptake probe uses what kinds of collimator - answerA cylinder shaped collimator which
limits the Area seen the crystal and eliminates background activity
The standard used for thyroid uptake studies - answerThe patient's capsule or another
capsule prepared at the same time and activity. Dilution not required for uptake probe
Splenic sequestration studies use what counter - answerThe uptake probe
The dose calibrator is - answerAn ionization chamber that measures gamma photon
dosages from thirty microcurie to curies. To measure beta radiation a correction factor is
needed because only high energy beta radiation can pass through the glass chamber
walls
A dose calibrator measures - answermeasures radioactivity in curies or bequerels rather
than in counts per unit time
A dose calibrator can accurately measure doses as low as - answerThirty microcuries
up to activities in the curie range
SPECT vs planar - answerSPECT has Greater sensitivity and resolution especially in
deep tissues or overlapping structures.
PET crystals must be thicker and denser than those in gamma cameras to - answerStop
the 511 kiloelectron volt photons produced during positron annihilation
The advantage of PET over SPECT - answerHigher resolution
When counting radiation for quantitative studies you should limit percentage of error to -
answerTwo percent at the ninety five percent confidence level
INSTRUMENTATION
Radiation exposure rates are measured by – answer Survey meters
Contamination surveys can be performed with - answerA Geiger Muller counter
A Geiger Muller counter is appropriate for contamination surveys because it -
answerHas a rapid response time and can detect a wide range of exposure rates
A Geiger Muller counter meets the NRC requirement for facilities to have - answerA
survey meter capable of detecting exposure rates from 0.1 millirems per hour to one
hundred millirems per hour
GM counters may be fitted with - answerAn end window probe or a pancake probe
The pancake probe - answerAllows the technologist to survey a larger area
The end window probe - answermust be pointed directly at a source for accurate
detection
Portable ionization chambers are also known as - answerCutie pies
Cutie pies or portable ionization chambers vs Geiger Muller counters - answerGeiger
Muller counters are more sensitive. Cutie pies are more accurate
The cutie pie is more accurate because - answerIt has a longer response time so the
exposure rate is calculated based on more data
The cutie pie is superior in measuring - answerHigh dose rates such as those in patient
doses, especially therapeutic doses
A well counter works by - answerUsing a Thallium activated sodium iodide crystal to
detect low levels of radioactivity
Compared to a gamma camera a well counter is - answerMore efficient
The well counter's sensitivity limits the instruments use because - answerActivities
greater than two microcuries can cause coincidence loss
When too many photons strike the crystal in a well counter - answerCounts are lost
while the instrument is in deadtime
, If the counting rate is very high in a well counter - answerIt may cause perpetual
deadtime paralysis
The well counter is used for - answerWipe tests to detect very low levels of removable
contamination
Well counter use in non imaging studies - answerused to count blood plasma and urine
samples when Standards for blood volume or Schilling tests are diluted to a known
percentage of the original patient dosage
Uptake probe - answerUses a sodium iodide crystal to quantitate activity within a
patient. May be connected to the spectrometer used by the well counter
The uptake probe is not as sensitive as the well counter because of - answerDetector to
source geometry
Uptake probe uses what kinds of collimator - answerA cylinder shaped collimator which
limits the Area seen the crystal and eliminates background activity
The standard used for thyroid uptake studies - answerThe patient's capsule or another
capsule prepared at the same time and activity. Dilution not required for uptake probe
Splenic sequestration studies use what counter - answerThe uptake probe
The dose calibrator is - answerAn ionization chamber that measures gamma photon
dosages from thirty microcurie to curies. To measure beta radiation a correction factor is
needed because only high energy beta radiation can pass through the glass chamber
walls
A dose calibrator measures - answermeasures radioactivity in curies or bequerels rather
than in counts per unit time
A dose calibrator can accurately measure doses as low as - answerThirty microcuries
up to activities in the curie range
SPECT vs planar - answerSPECT has Greater sensitivity and resolution especially in
deep tissues or overlapping structures.
PET crystals must be thicker and denser than those in gamma cameras to - answerStop
the 511 kiloelectron volt photons produced during positron annihilation
The advantage of PET over SPECT - answerHigher resolution
When counting radiation for quantitative studies you should limit percentage of error to -
answerTwo percent at the ninety five percent confidence level
