Test your basic knowledge |

Radiology 2

Subjects : health-sciences, radiology

Instructions:

Answer 50 questions in 15 minutes.
If you are not ready to take this test, you can study here.
Match each statement with the correct term.
Don't refresh. All questions and answers are randomly picked and ordered every time you load a test.

This is a study tool. The 3 wrong answers for each question are randomly chosen from answers to other questions. So, you might find at times the answers obvious, but you will see it re-enforces your understanding as you take the test each time.

1. How does kVp affect patient exposure
Higher kVp = low exposure
Insufficient or improper washing
X-rays hit phosphor screen creating florescent light that exposes the film
Density

2. What is formed when high speed electrons strike the target
X-ray and heat
Not as sharp and detailed as the intraoral image
Shadow around the tooth
White blood cells - red blood cells - immature reproductive cells - epithelial cells - connective tissue cells - bone cells - nerve cells - brain cells - muscle cells

3. when taking a radiograph - you pulls the cone out about 6 inches from the patient's face. What is the result
1/6th of a second
Air space and soft tissues
Increase the area of radiation exposure
nasal septum - ant. nasal spine - nasal fossa - median palatine suture - incisive foramen

4. Mand lateral/canine anatomy
Tori
Not centered on sensor
Oral piercings - earings - glasses - necklaces - facial piercings - hair pins - hearing aids - dentures - and retainers
As low as reasonably achievable

5. How far from the work surface must the safelight be mounted
Patient positioned too far foward in the focal trough
Stop taking xrays and evaluate all equipment and techniques to ensure safety
4 feet
Top of film delineated by a straight line then dark

6. What Size film is 15/16 x 1 9/16
Oral piercings - earings - glasses - necklaces - facial piercings - hair pins - hearing aids - dentures - and retainers
bisecting was used b/c of the distortion of the elongated root - the roots appeared long b/c the vertical angulation was inadequate
Insufficient vertical angulation
No. 1

7. What is reticulation
Faster film = lower definition and detail
Not as sharp and detailed as the intraoral image
Patient positioning
Cracking of the emulsion caused by excessive temp diff. b/w any darkroom solutions

8. What are filters made out of...
Aluminum
Cathode - filament - focusing cup
Gently agitating the hanger up and down a few times
BW

9. What is the most likely cause of a film with very poor definition
5(n-18)
2.5 mm
Patient movement
1/3-1/2

10. What parts of the x-ray machine are included in the anode circuit
Check the processing chemical - particularly the developer
Original - undeflected - useful beam
All of the ant. teeth will appear blurred and narrowed in width
Copper stem - tungsten target - radiator

11. What Size film is 1 1/16 x 2 1/8
Decrease kVp by 15 and double exposure time = 10 mA 60 impules 75 kVp
No. 3
#1 or #2 - placed so the edge of the receptor lines up behind the distal of the canine before the eruption of the permanent 2nd molar; - after the eruption of the perm. 2nd molar - 2 posterior PA's should be taken per quadrant
Clinical exam

12. What 3 types of cells are most radioresistant
Nerve - brain - muscle
Long-term dose
2.5 mm
Blue light sensitive films

13. Size film used for BW on adults when only one film is taken on each side
1/5 exposure time for edentulous
Perpendicular to the film - parallel to the bite portion of the stabe
#3
2.75 inch

14. What is used to clean the screens inside of a cassestte
Patient movement
50 mSv or 5 REM
Soft cloth - non abrasive cleaner
Sterilize film holder devices or discard disposable image receptor holding devices

15. When taking a radiograph - you pull the end of the PID away from the patients face about 6 inches. How will this affect the radiographic image and patient exposure
Ionization
Patient movement
Lighter image - patient exposed to larger beam which will increase exposure
8-16 inches

16. What type film is faster - intraoral or extraoral
#1
Clear/blue in the area of overlap b/c fixer will not remove all crystals
All of the ant. teeth will appear blurred and narrowed in width
Extra oral

17. What is the best way to reduce exposure to patient
Highest of the 2 ridges - about the level of the cervical 3rd - behind the 2nd and 3rd molars
Faster film = lower definition and detail
Rectangular collimation
X-rays hit phosphor screen creating florescent light that exposes the film

18. when taking a PANO radiograph - the patient is placed too far into the machine. How will the radiograph appear
All of the ant. teeth will appear blurred and narrowed in width
Cosmic - naturally occuring radiation from earth - radiation for radioactive materials
Occlucal
Dark film is from over exposure and improper packet placement for strange looking teeth and not being able to determine What film is

19. Max lat. canine anatomy
CCD (direct) - CMOS (direct) - PSP (indirect)
Nasal fossa - max sinus
Old or contaminated processing solutions -exposure to chemical fumes -faulty safelight -scatter radiation
Insufficient or improper washing

20. What is the best method of protecting the thyroid gland from radiation?
Positioning the arches too far foward
Thyroid collar - lead and lead-equivalent sprons are availaable with or without an attached thyroid collar
Short
20 seconds

21. you notice that a radiograph taken several months ago is brown and spotted. What happened
As close as possible
Soft tissue - air space
Insufficient or improper washing
Document patient's refusal and have them sign

22. 3 film holding devices used for paralleling
Sterilize film holder devices or discard disposable image receptor holding devices
Dentsply rinn - XCP - XCP-DS - flow dental RAPD
50 mSv or 5 REM
Evidence based selection criteria

23. What is the area of the skull that is in focus on a pano

24. How often are BW taken on children with high risk
Cathode - filament - focusing cup
WBC - RBC - immature reproductive cells
Every 6 mths
Copper stem - radiator and air space

25. What is the major diff. b/w particulate and electromagnetic radiation
20 min
50 mSv (5rem)
particulate radiation: made of protons - neutrons - electrons and alpha and beta particles; has mass -electromagnetic radiation: made of photons; no mass
Max sinus - zygoma - max tuberosity - coranoid process

26. What is the bremsstrahlung radiation
No. 4
Sv & Rem
Aka general radiation; stopping or slowing of the electrons of the cathode stream as they collide with the nuclei of the target atoms
Mand canal - external oblique ridge - beg. of ramus

27. What anatomical structures appear radiolucent on a dental radiograph
Excessive VA w/ PID positioned too steep enough away from zero degrees
Periapical examination - paralleling technique
Air space and soft tissues
Blue light sensitive films

28. What Size film is 7/8 x 1 3/8
GBX - 2
Excessive VA w/ PID positioned too steep enough away from zero degrees
No. 0
#2

29. How long does the first rinse last
Insufficient vertical angulation
max molars have 3 roots - mand have 2 roots
20 seconds
Soft cloth - non abrasive cleaner

30. What happens in the fixer
Ionization
X-rays hit phosphor screen creating florescent light that exposes the film
Before fixing
Removes the unexposed silver halide crystals

31. What control factors effect contrast
#1 or #2 - placed so the edge of the receptor lines up behind the distal of the canine before the eruption of the permanent 2nd molar; - after the eruption of the perm. 2nd molar - 2 posterior PA's should be taken per quadrant
#2
KVp
Soft cloth - non abrasive cleaner

32. How does the reproductive capacity of a cell correlate with radiosensitivity
#2
Insufficient vertical angulation
Rapidly producing cells are more sensitive to radiation
Faster film = lower definition and detail

33. A properly exposed film appears completely black. when was is exposed to white light
Before fixing
Air space and soft tissues
2.75 inch
Insufficient or improper washing

34. What would happen to a film that is placed in the fixer prior to development
Blank or clear (takes all of the crystals off)
Duplicate - which will go to the insurance comp.; office keeps best copy
#0
Higher temp. increases film fog - so radiographer should consult a time-temp. development chart to adjust developing time appropriately; developing time will decrease

35. What type PID significantly reduces exposure to the patient
8-16 inches
underexposure-underdevelopment -depleted developer solution -excessive fixation (takes all crystals off)
As low as reasonably achievable
Rectangular collimations

36. Your dentist asks you to take a FMS on a 65 yr old edentulous patient. How many exposures will you take? which exposures are not necessary? What intraoral technique will you use? What might be better than a FMS?
Check the processing chemical - particularly the developer
take 14 radiographs -omit the BW -paralleling should be technique of choice -panoramic might be better than FMS
Filtration and collimation
Absorb scatter radiation and prevent fogging

37. How are indirect exposure films exposed
B/c of its stability to produce a large volume of radiographs in a short amount of time
7 1/2 or 15 watt
#2
X-rays hit phosphor screen creating florescent light that exposes the film

38. Max. centrals anatomy
Erythema - vomitting - nausea - hemorrage - diarrhea - hair loss
Roentgen
Part that was fixed but not developed would be clear
nasal septum - ant. nasal spine - nasal fossa - median palatine suture - incisive foramen

39. The cells from most sensitive to least sensitive
Parallel
White blood cells - red blood cells - immature reproductive cells - epithelial cells - connective tissue cells - bone cells - nerve cells - brain cells - muscle cells
.25 mm
To distinguish b/w patient's right and left side

40. What radiographs are used to determine if a foreign object is located facially or lingually
Rectangular collimation
Decrease kVp by 15 and double exposure time = 10 mA 60 impules 75 kVp
Occlusal
Time b/w exposure and 1st clinically observable symptoms

41. What controls the speed with which the electrons travel from the cathode to the anode
Beam is perpendicular to the imaginary line that bisects the angle formed by the long axis and the film
KVp
Cracking of the emulsion caused by excessive temp diff. b/w any darkroom solutions
Removes the unexposed silver halide crystals

42. What type of angulation is used when taking radiographs of the mand. arch
Coulombs/kilogram(C/kg) & Roentgen (R)
Far object-image receptor distance
Negative
Rectangular collimation and fast film speed

43. What would cause a film to be too dark
Overexposure -overdevelopment -developer is too strong -not enough fixation -exposure to white light -improper safelighting
Produced by internal barriers in tube head (ex: glass and insulating oils)
Roentgen
Short-term dose

44. How are stabe film holders sterilized b/w uses
Sterilize film holder devices or discard disposable image receptor holding devices
7 1/2 or 15 watt
Panoramic cape
Cracking of the emulsion caused by excessive temp diff. b/w any darkroom solutions

45. Size film used for PA's on adults
25
#2
20 min
As close as possible

46. What is the term to describe the overall blackness of a radiograph
Movement caused by the patient - slippage of the image receptor - or vibration of the tube head
Density
Before fixing
1/3-1/2

47. What is the max. permissable fose for radiation workers in systeme interventional units
Duplicate - which will go to the insurance comp.; office keeps best copy
locate retained roots -locate unerrupted or impacted teeth -evaluate for diseases and lesions -locate foreign bodies -reveal presence of salivary stones (sialothiths) -aid in evaluating fractures -size and shape of tori -aid in examining patients wit
Incorrect horrizontal angulation
50 mSv (5rem)

48. According to principles of shadow casting - preferred source-object distance
The most distal tooth should be captured in full as well as a few mm of bone level behind the most distal tooth
Left side
Cut exposure time by 1/3
As far as practical

49. which dose of radiation is more biologically damaging
Chronic low-level exposures/long term dose; causing cancer - cataracts - low birth weight - genetic mutations - and embryological defects
A form of radiation originating from an atom following removal of an electron or excitation of an atom
Nerve - brain - muscle
6 ft

50. When can the films be exposed to white light
#3
Not centered on sensor
After 2-3 min of fixing if needed
particulate radiation: made of protons - neutrons - electrons and alpha and beta particles; has mass -electromagnetic radiation: made of photons; no mass