ARRT practice questions Flashcards
Which material to use as primary shielding around beta-emitting radionuclide, such as phosphorus-32?
Plexiglas, bc absorbers w/ larger atomic nuclei produce more Bremsstrahlung radiation than absorbers w/ smaller atomic nuclei
Amount of ionizing radiation from natural environment a person receives in U.S. per year
3 millisieverts (mSv)
When X-rays strike human body, which may occur?
-Cells may be damaged, leading to cell death or cell repair
-Cells may be damaged, then repaired incorrectly, leading to disease
-X-rays may pass thru body, or bounce off it, without affecting cells
Tech receives ionizing radiation exposure of 2uSv sitting 1 meter from X-ray source. If tech moves 3 meters away from source, what would be exposure?
0.22 uSv
Inverse square law.
Distance tripled 1 to 3
3 squared = 9
2 divided by 9 = 0.22
Typical pairing of radiation source & dosage
40 millisievert (mSv) for adult patient w/ full body CT scan
Iodine-125 is low-energy gamma-emitting isotope used in brachytherapy for certain tumors, such as carcinoma of prostate. Which is most accurate regarding type of hazard this isotope presents?
More dangerous when exposure is internal bc it’s taken up easily by thyroid gland
X-rays & gamma rays are absorbed effectively by ____
Lead
Barium sulfate
Depleted uranium
Linear no-threshold model (LNT) of radiation biological effects is derived EXCEPT ___
Cells have capability of repairing radiation-induced damage to DNA
Which of following materials are effective in shielding against alpha radiation?
Lead aprons
Glass window
Surgical scrubs
Radiation dose limit over course of a pregnancy
5 millisieverts (mSv)
Amount of energy converted to X-rays when electrical current is supplied to X-ray tube
Approximately 1% of energy converted to X-rays
Voltage supplied to X-ray tube
30 to 150 kilovolts (kV)
Which of following is true regrading tomography?
Positron emission tomography (PET) makes use of device that detects gamma rays
Beam of X-ray photons leaving X-ray tube focus can be described as having a ___ nature
heterogenous – emitted photons have variety of energies
Which is functional study to demonstrate degree of AP motion in cervical spine?
Flexion & extension laterals
Contraction & expansion of arterial walls w/ forceful contraction & relaxation of heart is called ___
pulse
Annual dose limit of student radiographer younger than 18 years
0.1 rem (1mSv)
Which can be transmitted via infected blood?
HIV
xx TB
xx lyme disease
xx dengue fever
Patient’s feeling of spinning, or room spinning about him
veritgo
Principal function of X-ray beam filtration
Reduce patient skin dose
xx - reduce scatter radiation
xx - reduce image noise
xx - reduce operator dose
Protective control booth of radiographer is a ___ barrier
secondary
Most common site for intravenous injection of contrast agents
antecubital vein
–when antecubital vein is not accessible, then basilic vein is used
Apex of heart is formed by the ___
left ventricle
To reduce back strain w/ transferring patients from stretcher to X-ray table, you should ____
pull the patient
xx - bend at the waist & pull
Dose of 0.25 Gy or 25 rad to fetus during 3rd/4th week of pregnancy is more likely to cause ____
skeletal anomalies
(occurs during weeks 1-4)
xx - neurologic anomalies (occurs during weeks 5-8)
Which pathologic condition requires increase in exposure factors?
ascites
xx - obstructed bowel
Period of development when fetus is most radiosensitive
first trimester
Patient recumbent position w/ head lower than the feet
Trendelenburg position
Myelography - contrast medium is injected into the ___
subarachnoid space between 3rd & 4th lumbar vertebrae
Best way to control voluntary motion
Patient suspends respiration
xx - short exposure time
QC program is for ___
Film processors
X-ray equipment
CT scanners
Which factors affect radiation damage to biological tissue?
Radiation quality
Absorbed dose
Size of irradiated area
Involuntary motion caused by ____
Peristalsis
Pain
Spasm
Sources of secondary radiation include:
Leakage radiation
Scatter radiation
xx - Background radiation
xx - Cosmic radiation
Which is NOT associated w/ acute abdominal distress?
-Extreme diarrhea
-Rigid abdomen
-Nausea/vomiting
-Extreme thirst
Extreme diarrhea
Advantages of 35mm cine film vs. 16mm cine film
Larger filming area = higher resolution
Recording of more info
xx - less expensive
What to perform when adult patient experiences cardiac/respiratory arrest?
Call a code & begin CPR
xx - assess brachial pulse
1st location: carotid pulse
2nd location: femoral pulse
Infants: brachial pulse
What part of X-ray tube is negative side & has 2 primary parts: a filament & focusing cup
Cathode
Which is true if matrix size increases, yet FOV (field of view) is unchanged?
Pixel size decreases
Resolution increases
Collimator tests must be made to be accurate within ____
2% of SID
Type of crystal used in optically stimulated luminescence (OSL) dosimetry system
Aluminum oxide
To demonstrate apophyseal joints of lumbar vertebrae within AP projection, the patient is rotated how many degrees?
45 degrees
Increasing kVp of X-ray beam results in photons having ___
shorter wavelength
Grid ratio = relationship between height of the lead strip & the ___
distance between the lead strips
Bit depth describes ___
grayscale availability
Medication route - parenteral
Parenteral routes:
intravenous
intramuscular
intracardiac
Normal range for creatinine
0.6 - 1.5 mg/100 mL
Syncope
fainting
Patient position following syncopal episode & low blood pressure
Sims (aka recovery position)
Patient w/ long bone fracture - best method to manipulate affected extremity
Manipulate both ends of extremity simultaneously & in unison
Essential lab value must be verified before administering intravenous iodinated contrast media in regards to kidney function
Creatinine
Type of manual respirator
Ambu
xx - ECMO
xx - mechanical ventilator
xx - CPAP
Patient having CAT scan of head. After injecting contrast, patient complains of nausea & problems breathing. What type of shock?
Anaphylactic
Function of housing around X-ray tube
Minimizes radiation leakage
Erythema
reddening of irritated skin
What position when patient lies flat on back & head is lower than feet?
Trendelenburg
Best time to use log rolling method to move patient is when patient may have ___
spinal injury
What restricts useful X-ray beams from causing unnecessary exposure?
Collimation
Target interaction caused by deceleration of cathode electron
Bremsstrahlung (braking radiation)
