FINALS L1 & L2 Flashcards
Dose limit for Occupational Radiation Exposure
20 mSv / yr
General X-ray activity must ______
Not Exceed 1 mSv / yr
It contributes to the highest occupational exposure of diagnostic x-ray personnel.
Fluoroscopy
Personnel exposure is ________ related to the x-ray beam on-time.
Directly
An X-ray tube over the table is advantageous in terms of _______
Image Quality
An X-ray tube over the table is disadvantageous in terms of higher personnel exposures, mainly due to (2):
- High Levels of Scatter Radiation
- High Levels of Leakage Radiation
It is best to position the x-ray tube _______ during mobile and C-arm fluoroscopy
Under the Patient
What modality contributes to higher personnel exposure due to longer fluoroscopic x-ray beam on-time ?
Interventional Radiology
Higher exposures in IR are also caused by what other two factors ?
- Absence of Protective Curtain
- Use of Cineradiography
Dose limit for IR
500 mSv / yr
________ must be provided for interventional radiologists
Extremity Monitoring
Which modality manifests low personnel exposures due to low kVp operation ?
Mammography
Low kVp operation = ______
Less Scatter Radiation
Which modality manifests low personnel exposures due to fine collimation and sole presence of secondary radiation in the examination room ?
Computed Tomography
Occupational exposure for nursing personnel and others working in the operating room and ICU is ______
Near Zero
TRUE OR FALSE
It is necessary to provide occupational radiation monitors for OR / ICU personnel
FALSE
It is NOT necessary to provide occupational radiation monitors for OR / ICU personnel
Which contributes to the highest occupational exposure of diagnostic x-ray personnel ?
Mobile Radiology
Who are the people that should wear occupational radiation monitor (4):
- Radiologic Technologist
- Anyone who is required to immobilize or hold patients.
- Personnel who regularly operate C-arm fluoroscope
- Personnel who are regularly in the immediate vicinity of C-arm fluoroscope
The dose of radiation that would be expected to produce no significant radiation effects
Maximum Permissible Dose (MPD)
It is specified only for occupational exposure and serves as a replacement for MPD
Dose Limit (DL)
Current DL = _____
1 mSv / Week
NCRP DL Recommendations:
Annual Effective Dose for Occupational Exposures = ________
50 mSv
NCRP DL Recommendations:
Cumulative Dose for Occupational Exposures = ________
10 mSv x age
NCRP DL Recommendations:
Occupational equivalent annual dose for Lens of the Eye = ______
150 mSv
NCRP DL Recommendations:
Occupational equivalent annual dose for Thyroid, Skin, Hands, and Feet
500 mSv
Annual Negligible Individual Annual Dose
0.01 mSv
Radiation Weighting Factor:
X and gamma rays, electrons
1 Wf
Radiation Weighting Factor:
10 keV - 100 keV & >2 MeV - 20 MeV
10 Wf
Radiation Weighting Factor:
> 100 kev - 2 MeV
20 Wf
Radiation Weighting Factor:
Protons
2 Wf
Radiation Weighting Factor:
Alpha Particles
20 Wf
Radiation Weighting Factor:
> 20 MeV
5 Wf
Enumerate Various Tissues with their corresponding Tissue Weighting Factor (12) :
- Gonad = 0.20
- Active Bone Marrow = 0.12
- Colon = 0.12
- Lung = 0.12
- Stomach = 0.12
- Bladder = 0.05
- Breast = 0.05
- Esophagus = 0.05
- Liver = 0.05
- Thyroid = 0.05
- Bone Surface = 0.01
- Skin = 0.01
RATIONALE MNEMONICS:
0.20 (Gago)
0.12 (Ang - Cringe - Lung - Sobra)
0.05 (Bo - Bo - Easy - Liver - Talaga)
0.01 (Bull - Shit)
The pregnancy period most sensitive to radiation exposure occurs _______
Before Birth
Least hazardous period of radiation exposure during pregnancy
1st to 2nd Week
Biologic response to occur in 1st to 2nd Week of Pregnancy
Resorption of the Embryo
The 2nd to 10th Week of Pregnancy is called as the period of _____ wherein the major organs of the fetus are developing,
Major Organogenesis
The principal response during the 2nd and 3rd Trimesters of pregnancy is ______
Malignant Disease during Childhood
Spontaneous abortion after irradiation during the first 2 weeks of pregnancy is unlikely at radiation doses _____
< 25 rad
A 1 % increase in congenital abnormalities is estimated to follow a fetal dose of _____
10 rad
Administrative protocols to garner patient information, to ensure the prevention of the irradiation of patients who are pregnant include (3):
- Elective Booking
- Patient Questionnaires
- Posting
The most direct way to ensure against the irradiation of an unsuspected pregnancy by determining the time of the patient’s previous menstrual cycle
Elective Booking
TRUE OR FALSE
The patient, herself, may indicate her menstrual cycle
TRUE
These are utilized when neither elective booking nor request forms seems appropriate for a diagnostic imaging service
Posting / Posting Signs / Post Signs
Three options often considered for pregnant medical radiation workers (3):
- No Change in Assigned Working Duties
- Change to Another Area Where the Radiation Exposure may be Lower
- Change to a Job that has Essentially No Radiation Exposure
