nuc med instrumentation exam 1

who is responsible for discovering x rays

william roentgen

who is responsible for discovering radium

marie curie

3 gas filled detectors

dose calibrator

ionization chamber

geiger counter

2 scintillation detectors other than anger camera

well counter

thyroid probe

example of a semiconductor detector

intraoperative probe

4 ancillary instruments in nuclear medicine

xenon trap

centrifuge

glucometer

Istat

how often is dose cal constancy done

daily

how often is dose cal linearity done

quarterly

how often is dose cal accuracy done

annualy

how often is dose cal geometry done

upon instal and after repair

3 insulator examples

air

gas (argon)

rubber

Ohms Law

V=IR

Lowest energy shell according to bohrs model

Q shell

Highest energy shell according to bohrs law

K shell

3 charged particles in nuclear medicine

alpha

beta (-)

Positron

True ionization, excitation, and bremsstrahlung interactions all occur with what

charged particles

Photoelectric effect and compton scattering are interactions with

photons

2 instuments that require close examination of counting statistics are

thyroid probe

well counter

radiation decay follows what model

poisson model

which is more efficient gas filled detector or solid crystal

solid crystal

which is more efficient thyroid probe or well counter

well counter

what does a well counter measure

activity

disintegrations coming off of a dose

what is electrical capacitance

the capability of a material or device to store energy in the form of electrical charge

common capacitors in nuclear medicine

the one present in gas filled dose calibrator

who do atoms with higher atomic numbers have higher binding energies

the larger the nucleus the more protons thus the more electrical force in the nucleus increasing its ability to hold orbiting electrons in palce

ionization vs true ionization

true ionization is CHARGED PARTICLES ionization is any radiation that causes ejection of electrons leaving 2 ions

2 variables that effect radiation detection of TC-99m

1) randomness of radiation interactions outside of typical decay (xrays created after ionization)

2) electrical fluctuations from common outlets

what is chi squared used for

Chi squared takes a group of counts and compares them to the expected poisson model thus checks for errors greater than the predicted poisson model which can identify deficiency or malfunction

how often is chi squared done

quarterly

MDA

minimum detectable activity

amount of activity that increases counts in a statistically significant manner (> 3SD)

what devices require MDA

any counting device

what component do energy sensitive detectors have

pulse height analyzer

4 examples of energy sensitive detectors

Gamma camera

well counter

thyroid probe

surgical probe

Coulumb's Law

F=kq1q2/r^2

define and describe the standard deviation

a measurement of precision

shows the spread of data from the center mean

what makes a conductor good at energy transfer

They LOOSLY hold valence electrons thus they move easily

what makes an insulator good at not transfering energy

They have a FULL VALENCE SHELL this electrons cannot move easily

Semiconductor valence shell

Full valence shell but it takes very little energy to move electrons

what does a resistor measure

The change of flow