Download Radiology Exam Questions and Answers: A Comprehensive Guide for Students and more Exams Advanced Education in PDF only on Docsity!
CAMRT EXAM QUESTIONS AND ACCURATE ANSWERS
How far away must the operator stand from the xray tube if not covered with lead? - ANSWER 3 meters
90% of man made radiation to the population is related to? - ANSWER Medical Radiography and Dental
For each peak xray voltage, what lead equivalent is required?
100kV or less (o-100) Between 101kV-149kV 150kV or greater (150+) - ANSWER 0-100kV = 0.25mm of lead
Greater than 100kV but less then 150kV = 0.35mm of lead
150kV or greater = 0.50mm of lead
What protective equipment is worn when performing interventional procedures - ANSWER Full wrap around protective gowns of 0.50mm pb in the front panels and 0.25mm pb in the back panels
Thyroid shields with an equivalent of 0.50mm of pb
Lead drapes/curtains mounted to II of 0.25mm of pb at 100kv
What lead equivalent do protective gloves/ gauntlets need to have? - ANSWER 0.25mm of pb
What lead equivalent must ceiling mounted lead screens and moveable shields provide?
What are the annual radiation dose limits for radiation workers? - ANSWER Whole body= 20mSv Lens of eye= 150mSv Skin = 500mSv Hands = 150mSv All other organs = 500mSv
For pregnant women an effective dose of 4 mSv must be applied for the remainder of the pregnancy from all sources
What are the annual radiation dose limits to members of the public? - ANSWER Whole body = 1mSv Lens of the eye= 15mSv Skin = 50mSv Hands = 50mSv All other organs = 50mSv
these also apply for students
What are primary protective barriers? Give examples - ANSWER Primary barriers provide shielding from the direct xray beam. Such as, the walls and floor where the tube can be directed
-Wall behind the wall bucky -Floor under the table
HVL of Aluminum for given tube voltages? (70kV-150kV) - ANSWER 70: 2.5mm 80: 2.9mm 90: 3.2mm 100: 3.6mm 110: 3.9mm 120: 4.3mm 130: 4.7mm 140: 5.0mm 150: 5.4mm
How often should IP's and cassettes be cleaned and inspected? - ANSWER Cleaned: monthly Visual check: Weekly
What is daily QC tests for CR/DR/Fluoro/CT equipment - ANSWER -Warm up (all) -Meter operation (all) -Equipment condition (all) -System movements (fluoro) -Visual check of electronic display devices (all)
What are weekly QC tests for CR/DR/Fluoro/CT equipment - ANSWER -Visual inspection of cleanliness of system (all) -Laser film printer operation (all) -CT # accuracy -CT noise -CT uniformity
What are monthly QC tests for CR/DR/Fluoro/CT equipment - ANSWER -Cassette,
screen, IP plate cleaning (CR) -Retake analysis (CR/DR) -Electronic display device performance (all) -Laser film printer operation (all) -CT slice thickness -CT # calibration -CT # linearity
What should the monthly retake analysis be below? - ANSWER 5%
What are quarterly QC tests for CR/DR/Fluoro/CT - ANSWER -Collimator operation (CR/DR/Fluoro) -Interlocks (all) (on doors to prevent exposure if door is open) -Compression devices (Fluoro) -Table angling/motion (Fluoro) -Fluoro protection devices (lead drapes = .25mm of pb) -CT patient support movement -CT spatial resolution -CT low contrast detectability
What are the annual QC tests for CR/DR/Fluoro/CT - ANSWER -Accuracy of loading factors (CR/DR/fluoro) -Output reproducibility -Output linearity -Beam filtration -AEC -Beam/light field alignment
Ratio = h/D Describe bit conversions for grids - ANSWER 5:1 Grid: 1 bit 8:1 / air gap: 2 bits 12:1 grid: 2.5 bits SID bit conversions - ANSWER 100cm->122cm: 0.5 bit 100cm->180cm: 1.5 bit 122cm-> 180cm: 1 bit every 25cm change is a 0.5 bit change
Bit changes for part thickness - ANSWER Every 5cm change = 1 bit
What artefacts will result in grid cut off with a parallel grid? - ANSWER -SID too small -Angling against grid lines -Grid and CR not perpendicular
What artefacts will result in grid cut off with a focussed grid - ANSWER - Incorrect SID (off focus) -Angling against grid lines
- Off center
- Grid and CR not perpendicular -Upside down grid
What does the autotransformer do? - ANSWER Provides selection of a precise, controllable voltage
What does the line compensator do? - ANSWER Monitors the voltage supply to the xray imaging system and normalizes that voltage to exactly 220 V.
What does the high voltage generator do? Identify its 3 components. - ANSWER Raises voltage from from the autotransformer. Volts --> kV
- High voltage transformer
- Filament Transformer
- Rectifiers
What is the function of the rectifier? - ANSWER To switch current from AC to DC so current is flowing in one direction
What is the cathode filament made up of? - ANSWER Thoriated tungsten, due to its high melting point. Keeps tungsten from coating the inside of the glass enclosure and causing tube failure (gassy tube)
What is the anode target usually made of? - ANSWER Tungsten with Rhenium - Rhenium adds mechanical strength and better heat capacity
May layer graphite and molybdenum under the target, both are lighter making the anode lighter and easier to rotate
3 reasons why Tungsten is the material of choice - ANSWER 1. High atomic #: increase xray production efficiency
- Thermal Conductivity: Effective at dissipating heat
- High melting Point: Withstand high current without pitting/bubbling/melting
Two parts of induction motor, what they do? - Rotor: Inside the tube enclosure Stator: Outisde the tube enclosure
Both serve to rotate the anode
nkV: increase quantity nSID: decrease quantity nFilters: decrease quantity
Explain how each of these affects xray QUALITY
-increase mAs -increase kV -increase SID -increase filtration ANSWER mAs: no change kV: increase quality SID: no change Filters: increase
What is attenuation ANSWER Product of absorption and scatter
3 factors contributing to increased scatter ANSWER 1. High kV
- Increase xray field size
- Increased patient thickness
What is orthostatic hypotension? ANSWER Low blood pressure due to standing upright after sitting/lying
To visualize the left Z joints on an L spine in what direction should the patient be
obliqued? - ANSWER LPO or RAO
Final placement for these lines:
PICC NG Swan Ganz - ANSWER PICC: SVC NG: stomach Swan Ganz: Left or Right pulmonary artery
Describe optical density and contrast - ANSWER Optical Density: degree of blackening of an image, controlled by mAs
Contrast: difference in density between 2 areas, controlled by kV
If pedicle sits too far anterior on oblique L spine (too close to lateral border of vertebral body) - ANSWER Under obliqued
On an AP knee projection, how is the angle determined? - ANSWER By the patients hip measurement 0-18cm = caudad angle 19-24cm = no angle 25cm+ = cephalad angle
Which vessels ascend through the cervical transverse foramina - ANSWER Vertebral arteries
How to position for a dens view on a trauma patient - ANSWER Collar tilts the chin up. Align the CR to the IOML
--Squamous --Lambdoid
Name the 4 suture joints on the skull - ANSWER --Bregma (midline, anterior) --Lambda (midline, posterior --Pterion (anterior) --Asterion (posterior)
Name the branches of the aorta from right to left - ANSWER --Right common carotid --Left common carotid --Left subclavian
Name the heart valves - ANSWER Tricuspid valve: b/w RA and RV Mitral (bicuspid) valve: b/w LA and LV Pulmonary Valve: b/w RV and pulm trunk Aortic valve: b/w LV and aorta
Describe the Circle of Willis from posterior to anterior - ANSWER
Describe the mnemonic for the carpals - ANSWER Some (scaphoid) Lovers (Lunate) Try (Triquetral) Positions (Pisiform) That (Trapezium) They (Trapezoid) Cant (Capitate) Handle (Hamate)
What views will demonstrate the sphenoid sinus - ANSWER Lateral SMV Open mouth waters
What is diploe, where is it located - ANSWER layer of cancellous bone b/w the internal and external layer of compact bone in the skull. It contains marrow and veins.
The bones that make up the skull cap - ANSWER Frontal, Parietals, and occipital
Bones that make up the skull floor - ANSWER Temporal bones, ethmoid, sphenoid, occipital
Describe the 2 fontanelles of the skull and when they close - ANSWER Anterior fontanelle occurs at the bregma suture, closes at 18 months
Posterior fontanelle occurs at the lambda suture, closes at 8 weeks
What is the crista galli? - ANSWER attachment for falx cerebri
Adjustments to kV and mAs for a small/medium or large plaster cast - ANSWER Small/ Medium: +5-7kV or +50%-60% mAs Large: +8-10kV or + 100%mAs
Does a fiber glass cast require adjustment of technique? ANSWER No adjustment is required
What manipulations are required for pleural effusion and pneumothorax - ANSWER Pleural Effusion: +35%mAS
Generic name (trade name) -Epinephrine (adrenalin chloride) -Dopamine (intropin)
Antiarrhythmics example - ANS Correct arrhythmias of the heart
-Propranolol All beta blockers end in "lol"
Diuretics example - ANS Reduce blood volume by increasing urine output, can treat hypertension
-Furosemide (Lasix)
What are analgesics (NSAIDS) give examples - ANSWER Used to reduce pain. fever, and inflammation
-ibuprophen NSAID (motrin, advil etc) -acetaminophen (tylenol) -acetylsalicylic acid (aspirin)
Name the opiods used for intense pain (narcotics) - ANSWER -morphine sulfate (morphine) -meperidine (demerol)
- fentanyl (usually used with midazolam (versed) - a sedative
Name the opiods used for less severe pain - ANSWER -codeine sulfate (codeine)
-oxycodone (percocet)
what are antianxiety drugs (anticonvulsants) and give examples - ANSWER Treat anxiety and possible behavior disorders
-alprazolam (xanax) -lorazepam (ativan) -diazepam (valium)
Give an example of an antihistamine, who should you not give it to - ANSWER Diphenhydramine (Benedryl) Also epinephrine (adrenalin)
Someone who has asthma
What are anticoagulants, give examples - ANSWER They can be used to prevent clot formations, and also to prevent the extension of clots after a MI, stroke, PE, and venous clots
-Heparin sodium (heparin) inhibits formation of clots -Warfarin sodium (coumadin)
- acetylsalicylic acid (aspirin)
What are thrombolytic drugs, give examples - ANSWER They can break up newly formed clots, commonly referred to as tPA (tissue plasminogen activator)
-alteplase (activase) -retaplase (retavase) ending in "ase"
What is the normal adult pulse, and child pulse? -ANSWER Adult: 60-90bpm Child (4-10): 90-100bpm
What is the normal respiration rate for adults and children? - ANSWER Adult: 15- breaths per minute Infant: 30-60 breaths per minute
What is a vector? - ANSWER Any living organism that can carry a disease-producing virus
Describe the CR image readout process - ANSWER 1. Red laser light strikes IP
- Light gives energy to trapped electrons --> emission of light (Photo stimulated luminescence)
- Trapped electrons return to original state
- Energy emitted in form of blue light
- Light collected and converted to an electric signal
When rollers position the IP to be read its called translation
How do you calculate magnification factor - ANSWER Image size/ object size or SID/SOD
How do you calculate pixel size - ANSWER FOV/matrix size
What is the bit depth - ANSWER range of possible gray shades per pixel
What is the autotransformer? - ANSWER Corrects fluctuations in main power before the current moves to the generator
What is DQE - ANSWER Detective Quantum Efficiency which is how well an imaging system converts the exit beam into an output image. Increased DQE means less dose required to achieve the same image quality
What determines the dynamic range? - ANSWER The bit capacity of each pixel (the bit depth)
What is the difference between direct capture DR and indirect capture DR? - ANSWER Direct capture: xrays are converted directly to electric single by a photoconductor (no light conversion)
Indirect capture: xrays are converted to light first then converted to an electrical signal
Describe the layers of the CR cassette from front to back - ANSWER -Protective layer -Phosphor layer (F center) where latent image is stored (made with Barium Flour Halide Crystals) -Conductive layer (light reflective layer) -Support layer -Anti-halation layer (avoid light spread) -Backing layer with lead
For each of the steps, describe the 3 components in: Capture Coupling Collecting For the following: Indirect DR Direct DR - ANSWER Indirect DR Capture: Cesium Iodide
