Card Set Information

2014-05-06 15:34:47

Show Answers:

  1. Dose equivalent or Equivalent dose, effective dose is measured in what unit
    which takes into affect the quality factor of the radiation
    • REM or Sv or Eqd
    • dose equivalent or REM
  2. who has to wear a personnel dosimeter
    for employees that regularly exposed
  3. what is purpose of personnel dosimeters
    • indicate working habits and conditions
    • measure quantity of radiation exposure over time
    • records exposure to the are it is worn
  4. describe placement of the the dosimeters
    w/o lead apron at collar level
  5. TLD badges need what to excite the lithium fluoride crystals to read the amount of radiation
    the crystals need to be heated
  6. what level of radiation can tld badges read
  7. what are pros and cons to tld badges
    • pros: more accurate than film badge can be worn for 3 months crystals can be reused
    • cons: can only read once, calibrated dosimeters must be used
  8. dosimeters at the collar level serve what purpose
    provide an approx. dose equivalent to the thyroid and lens of the eye
  9. what is the lead equivalency of a lead apron
  10. List the main advantages and disadvantages of film badges
    advantages: cheap reliable can distinguish between types of radiation and energies

    disadvantages: only lasts a month, and are extremely sensitive to extreme temperature and humidity
  11. what is the function of a control badge
    it is a badge that is from the monitoring company that comes with other film badges it serves as basis for radiation while in transit, to ensure that false readings are not recorded the control badge is reported to the health care facility
  12. what is a personnel monitoring report
    a report that lists the deep eye and shallow occupational exposure of each covered person on a monthly, quarterly, year to date  and lifetime equivalent basis
  13. tld osl and film badges use sensing material to radiation
    • tld uses lithium fluoride
    • osl = aluminum dioxide
    • film badges = film
  14. what dosimeters are measured in mRem
    osl tld's film badges
  15. describe osl pro and cons
    • lightweight durable easy to carry can be worn up to 1 year
    • can measure readings as low as 1mrem
    • cons:
    • only records radiation near the part it is worn and exposure can read on day of occurrence not efficient if not worn every day
  16. list the main pros and cons to using a pocket dosimeter
    • pro: immediate readings, good for high exposure areas like when workers go back to nuclear fallout areas
    • cons: extremely expensive, doesnt provide a permanent record and must be read daily
  17. what are radiation survey instruments
    they monitor radiation and indicate the presence or absence of radiation
  18. identify diff types of radiation survey instruments of area monitoring
    geiger mueller - primary radiation survey instrument for area monitoring in the nuc med field used to locate a last radioactive source or detect low level radioactive contamination

    cutie pie an ionization chamber instrument that measures rate meter and cumulative exposure to radiation 1mR-several thousand and can detect exposure over a wide range of are within a few seconds
  19. what three detectors measure radiation in mR
    cutie pie geiger mueller instruments pocket dosimeters all measure radiation in air
  20. what are densitometers
    devices that measure radiation exposure in film badges of workers that reads the density of the film in the badge
  21. cell division:
    what are the types
    • multiplication process where one cell divides to form two or more cells.
    • mitosis and meiosis
  22. differentiate between mitosis and meiosis
    mitosis a parent cell divides to form two daughter cells identical to the parent cell

    meiosis is a special type of cell division that reduces the number of chromosomes in each daughter cell to half the number of chromosomes in the parent cell
  23. describe the four phases of cellular life
    • M (mitosis phase)
    • G1 (pre-DNA synthesis phase)
    • S(synthesis phase)
    • G2 (post DNA synthesis phase)
  24. what phase is most radiosensitive
    • Mitosis
    • late S phase
  25. during what phase can chromosomal damage from radiation be evaluated
    during metaphase of mitosis
  26. describe the four sub phases of mitosis
    prophase - first phase of cell division nucleus enlarges the dna complex coils tightly and chromatids become more visible

    metaphase - fibers between mitotic spindle form between the centrioles

    anaphase - duplicate centromeres migrate in opposite directions along the mitotic spindle and carry the chromatids to opposite sides of cell

    telophase - chromatids undergo changes in appearance by uncoiling and becoming long, loosely spiraled threads
  27. define let
    linear energy transfer is the average energy (ionizations) of deposited per unit length of track
  28. define RBE
    relative biologic effectiveness describes the relative capabilities of radiation with differing LET's to produce a biologic reaction
  29. define OER
    oxygen enhancement ratio is numerical value of the ratio of radiation dose required to cause a particular biologic response of cells or organisms in an oxygen deprived environment to the radiation dose required to cause an identical response under normal oxygenated conditions
  30. radiolysis
    when xray photons can interact with and ionize water molecules contained within human body, thereby separating them into other molecular components
  31. how does high LET radiation increase the risk of DNA damage
    with high let multiple strand breaks are possible are possible reapir enzymes are not effective at undoing damage cell death will occur
  32. differentiate between direct and indirect interaction
    direct interaction = biologic damage occurs as a result of ionization of atoms on essential molecules that may potentially cause these molecules to become inactive or functionality altered.

    indirect interaction - refers to effects produced by free radicals that are created by the interaction radiation with water they are highly reactive and result in cell death
  33. how does radiolysis produce cell damaging substances
    a hydroxyl radical (OH) can bond with another hydroxyl radical and form hydrogen peroxide (H202) a substance that is very posionous to the cell
  34. differentiate single strand break and double strand break
    single strand has what damage
    what fx has most damage in chromsoome
    single strand break - occurs commonly with low LET radiation enzymes are often capable of reversing this damage

    double strand break occurs with high LET and are often associated with the loss or gain of one or more nitrogenous bases

    base fx
  35. define mutation
    is the loss or change in a nitrogenous base in the DNA chain
  36. define covalent cross links
    are chemical unions create between atoms by the single sharing of one or more pair of electrons
  37. what are the possible effects of ionizing radiation on chromosomes
    • restitution - breaks rejoin with no visible damage
    • deletion - part of chromosome is lost at the next division
    • broken end arrangement - misshape chromsome produced
    • broken end rearrangement - geneticm aterial is rearranged damage not visible results in mutation
  38. describe the target theory
    states that when cel lDNA is directly or indirectly inactivated by exposure to radiation that cell will die
  39. what is pmat
    • prophase
    • metaphase
    • anaphas
    • telophase
  40. proportional counter
    serves no useful purpose in diagnostic imaging it is generally used in a laboratory setting to detect alpha and beta radiation
  41. what is caused by the low let radiation
  42. what type of interaction btw radiation and matter is most likely to occur between xradiation and human tissue
    indirect actions