NUCLEAR MEDICINE INSTRUMENTATION UPDATED ACTUAL Questions and
CORRECT Answers
Radiation exposure rates are measured by Survey meters
Contamination surveys can be performed with A Geiger Muller counter
A Geiger Muller counter is appropriate for contamination Has a rapid response time and can detect a wide range of
surveys because it exposure rates
A Geiger Muller counter meets the NRC requirement for A survey meter capable of detecting exposure rates from
facilities to have 0.1 millirems per hour to one hundred millirems per hour
GM counters may be fitted with An end window probe or a pancake probe
The pancake probe Allows the technologist to survey a larger area
The end window probe must be pointed directly at a source for accurate detection
Portable ionization chambers are also known as Cutie pies
Cutie pies or portable ionization chambers vs Geiger Geiger Muller counters are more sensitive. Cutie pies are
Muller counters more accurate
It has a longer response time so the exposure rate is
The cutie pie is more accurate because
calculated based on more data
High dose rates such as those in patient doses, especially
The cutie pie is superior in measuring
therapeutic doses
Using a Thallium activated sodium iodide crystal to detect
A well counter works by
low levels of radioactivity
Compared to a gamma camera a well counter is More eflcient
The well counter's sensitivity limits the instruments use Activities greater than two microcuries can cause coinci-
because dence loss
When too many photons strike the crystal in a well counter Counts are lost while the instrument is in deadtime
If the counting rate is very high in a well counter It may cause perpetual deadtime paralysis
Wipe tests to detect very low levels of removable contam-
The well counter is used for
ination
, used to count blood plasma and urine samples when
Well counter use in non imaging studies Standards for blood volume or Schilling tests are diluted
to a known percentage of the original patient dosage
Uses a sodium iodide crystal to quantitate activity within a
Uptake probe patient. May be connected to the spectrometer used by
the well counter
The uptake probe is not as sensitive as the well counter
Detector to source geometry
because of
A cylinder shaped collimator which limits the Area seen the
Uptake probe uses what kinds of collimator
crystal and eliminates background activity
The patient's capsule or another capsule prepared at the
The standard used for thyroid uptake studies same time and activity. Dilution not required for uptake
probe
Splenic sequestration studies use what counter The uptake probe
An ionization chamber that measures gamma photon
dosages from thirty microcurie to curies. To measure beta
The dose calibrator is radiation a correction factor is needed because only high
energy beta radiation can pass through the glass chamber
walls
measures radioactivity in curies or bequerels rather than
A dose calibrator measures
in counts per unit time
A dose calibrator can accurately measure doses as low as Thirty microcuries up to activities in the curie range
SPECT has Greater sensitivity and resolution especially in
SPECT vs planar
deep tissues or overlapping structures.
PET crystals must be thicker and denser than those in Stop the 511 kiloelectron volt photons produced during
gamma cameras to positron annihilation
The advantage of PET over SPECT Higher resolution
2/7
CORRECT Answers
Radiation exposure rates are measured by Survey meters
Contamination surveys can be performed with A Geiger Muller counter
A Geiger Muller counter is appropriate for contamination Has a rapid response time and can detect a wide range of
surveys because it exposure rates
A Geiger Muller counter meets the NRC requirement for A survey meter capable of detecting exposure rates from
facilities to have 0.1 millirems per hour to one hundred millirems per hour
GM counters may be fitted with An end window probe or a pancake probe
The pancake probe Allows the technologist to survey a larger area
The end window probe must be pointed directly at a source for accurate detection
Portable ionization chambers are also known as Cutie pies
Cutie pies or portable ionization chambers vs Geiger Geiger Muller counters are more sensitive. Cutie pies are
Muller counters more accurate
It has a longer response time so the exposure rate is
The cutie pie is more accurate because
calculated based on more data
High dose rates such as those in patient doses, especially
The cutie pie is superior in measuring
therapeutic doses
Using a Thallium activated sodium iodide crystal to detect
A well counter works by
low levels of radioactivity
Compared to a gamma camera a well counter is More eflcient
The well counter's sensitivity limits the instruments use Activities greater than two microcuries can cause coinci-
because dence loss
When too many photons strike the crystal in a well counter Counts are lost while the instrument is in deadtime
If the counting rate is very high in a well counter It may cause perpetual deadtime paralysis
Wipe tests to detect very low levels of removable contam-
The well counter is used for
ination
, used to count blood plasma and urine samples when
Well counter use in non imaging studies Standards for blood volume or Schilling tests are diluted
to a known percentage of the original patient dosage
Uses a sodium iodide crystal to quantitate activity within a
Uptake probe patient. May be connected to the spectrometer used by
the well counter
The uptake probe is not as sensitive as the well counter
Detector to source geometry
because of
A cylinder shaped collimator which limits the Area seen the
Uptake probe uses what kinds of collimator
crystal and eliminates background activity
The patient's capsule or another capsule prepared at the
The standard used for thyroid uptake studies same time and activity. Dilution not required for uptake
probe
Splenic sequestration studies use what counter The uptake probe
An ionization chamber that measures gamma photon
dosages from thirty microcurie to curies. To measure beta
The dose calibrator is radiation a correction factor is needed because only high
energy beta radiation can pass through the glass chamber
walls
measures radioactivity in curies or bequerels rather than
A dose calibrator measures
in counts per unit time
A dose calibrator can accurately measure doses as low as Thirty microcuries up to activities in the curie range
SPECT has Greater sensitivity and resolution especially in
SPECT vs planar
deep tissues or overlapping structures.
PET crystals must be thicker and denser than those in Stop the 511 kiloelectron volt photons produced during
gamma cameras to positron annihilation
The advantage of PET over SPECT Higher resolution
2/7
