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. Explain PSP
Photostimuable Phosphor Plate aka storage phosphor system -indirect digital imaging -captures analog data then processed in a laser scanning device -light is then converted into electrical signal that the computer uses to create the digital image
Check the processing chemical - particularly the developer
Step-wedge or test film
5 mSv or .5 REM

2. What would cause a film to be too light
Roentgen
underexposure-underdevelopment -depleted developer solution -excessive fixation (takes all crystals off)
Copper stem - radiator and air space
Rapidly producing cells are more sensitive to radiation

3. According to principles of shadow casting - preferred source-object distance
Mand canal - external oblique ridge - beg. of ramus
As far as practical
After 2-3 min of fixing if needed
Higher temp. increases film fog - so radiographer should consult a time-temp. development chart to adjust developing time appropriately; developing time will decrease

4. in which pericapical projection will the mental ridge be visible
Mandibular lateral/central
Beam is perpendicular to the imaginary line that bisects the angle formed by the long axis and the film
Erythema - vomitting - nausea - hemorrage - diarrhea - hair loss
On the back side of the tori

5. What type of x-rays have greater penetrating power - long or short wavelength?
Incorrect horrizontal angulation
Cosmic - naturally occuring radiation from earth - radiation for radioactive materials
Erythema - vomitting - nausea - hemorrage - diarrhea - hair loss
Short

6. What are the short term effects of radiation exposure
The most distal tooth should be captured in full as well as a few mm of bone level behind the most distal tooth
Lighter image - patient exposed to larger beam which will increase exposure
Far object-image receptor distance
Erythema - vomitting - nausea - hemorrage - diarrhea - hair loss

7. What is the collimator made out of...
Original - undeflected - useful beam
Time b/w exposure and 1st clinically observable symptoms
Lead
Not centered on sensor

8. What factors would decrease edge sharpness and increase magnification
Far object-image receptor distance
Long-term dose
KVp
After 2-3 min of fixing if needed

9. What is the main source of radiation exposure to the operator
Cathode - filament - focusing cup
Scatter/secondary radition
Paralleling; meets more principles of shadow casting
D - E - F

10. What part of the x-ray machine is responsible for providing the electrons
Premature contact with developer
Chronic low-level exposures/long term dose; causing cancer - cataracts - low birth weight - genetic mutations - and embryological defects
Filament
Rectangular collimation and fast film speed

11. What is the x-ray at the center of the primary beam called
Central ray
50 mSv or 5 REM
Eyewear - mask - and gown
Gelatin and silver halide crystals

12. What causes overlapping
Incorrect horrizontal angulation
Excessive VA w/ PID positioned too steep enough away from zero degrees
Parallel
Gelatin and silver halide crystals

13. What would cause a properly exposed film to appear dark?
Copper stem - radiator and air space
To distinguish b/w patient's right and left side
Overdevelopment -temp. too high -time too long -developer concentration too high -inadequate fixation -accidental exposure to light -improper safelighting
Vertical BW

14. What anatomical structures appear radiopaque on a dental radiograph
Top of film delineated by a straight line then dark
Overdevelopment -temp. too high -time too long -developer concentration too high -inadequate fixation -accidental exposure to light -improper safelighting
Cut exposure time by 1/3
Enamel - dentin - and bone

15. According to principles of shadow casting - How should the film be placed in relation to the tooth?
Blue tinted polyester acetate
Parallel
Failed safelight test - suggesting that the safelight conditions in the darkroom are fogging the film
50 mSv or 5 REM

16. What device is used to check quality of processing chemicals
Insufficient or improper washing
Blue light sensitive films
25
Step-wedge or test film

17. How are indirect exposure films exposed
Didn't push button completely
Periapical examination - paralleling technique
Short-term dose
X-rays hit phosphor screen creating florescent light that exposes the film

18. when duplicating radiographs - What side of the duplicating film is in contact with the radiograph to be duplicated
Overdevelopment -temp. too high -time too long -developer concentration too high -inadequate fixation -accidental exposure to light -improper safelighting
Mand canal - external oblique ridge - beg. of ramus
The emulsion side of the film is placed against the orginal radiograph with the nonemulsion side up
Time b/w exposure and 1st clinically observable symptoms

19. when taking a radiograph - you pulls the cone out about 6 inches from the patient's face. What is the result
Left molar PA
Increase the area of radiation exposure
Max sinus - zygoma - max tuberosity - coranoid process
Reduce size and shape of beam

20. What controls the speed with which the electrons travel from the cathode to the anode
No exposure - or fixer before developer
.25 mm
KVp
#2

21. What does alara stand for
B/c of its stability to produce a large volume of radiographs in a short amount of time
As low as reasonably achievable
Dentsply rinn stabe - BAI - dental SUPA
extraoral film

22. What is the purpose of collimation
Stop taking xrays and evaluate all equipment and techniques to ensure safety
Reduce size and shape of beam
Photostimuable Phosphor Plate aka storage phosphor system -indirect digital imaging -captures analog data then processed in a laser scanning device -light is then converted into electrical signal that the computer uses to create the digital image
50 mSv or 5 REM

23. How often should an FMS be taken on an adult with no significant medical history
#3
Photostimuable Phosphor Plate aka storage phosphor system -indirect digital imaging -captures analog data then processed in a laser scanning device -light is then converted into electrical signal that the computer uses to create the digital image
Take FMS on all new patients; recall adults with no sig. med. history only require BW and PA - if indicated
Depends on the needs of the patient - established after intraoral exam

24. What would cause a film to be too dark
Clear/blue in the area of overlap b/c fixer will not remove all crystals
Short-term dose
Overexposure -overdevelopment -developer is too strong -not enough fixation -exposure to white light -improper safelighting
Panoramic cape

25. Proper patient positioning for bisecting
To distinguish b/w patient's right and left side
Increase the exposure time
Max arch ala-tragus parallel to floor - mand arch
Method should be compensated for bisecting or paralleling

26. What is the bremsstrahlung radiation
Insufficient vertical angulation
Aka general radiation; stopping or slowing of the electrons of the cathode stream as they collide with the nuclei of the target atoms
Size of crystals - thickness of emulsion - radiosensitive dyes
Higher temp. increases film fog - so radiographer should consult a time-temp. development chart to adjust developing time appropriately; developing time will decrease

27. What is characteristic radiation
Max arch ala-tragus parallel to floor - mand arch
A form of radiation originating from an atom following removal of an electron or excitation of an atom
#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
Beam is perpendicular to the imaginary line that bisects the angle formed by the long axis and the film

28. What parts of the x-ray machine are included in the cathode circuit
Aluminum
Cathode - filament - focusing cup
Mand occlusal
1/6th of a second

29. How many impulses are in .25 seconds
Sterilize film holder devices or discard disposable image receptor holding devices
Cut exposure time by 1/3
15 impulses
#2

30. if the kVp is increased from 75-90 - What must be done to achieve a radiograph of comparible density
CCD (direct) - CMOS (direct) - PSP (indirect)
Large blank space is due to reversed image error or chemical contamination - missing apices is due to inadequate VA
decrease mA & time
detect pathological lesions -establish position of mental foramen -establish position of mand canal -determine quality & quantity of alveolar bone present

31. What is the name for the part of the target that is struck by electrons
Lateral cephalometric
Coulombs/kilogram(C/kg) & Roentgen (R)
Focal spot
Panoramic cape

32. How often should developing solutions be changed
underexposure-underdevelopment -depleted developer solution -excessive fixation (takes all crystals off)
PANO
Every 4 weeks
Soft cloth - non abrasive cleaner

33. What exposure would be useful in identifying salivary stones in the submandibular gland
20 seconds
Mand occlusal
Take FMS on all new patients; recall adults with no sig. med. history only require BW and PA - if indicated
Paralleling; meets more principles of shadow casting

34. when viewing a duplicated radiograph - you notice that the duplicate is too dark. What should you do to duplicating time to lighten the film
Max arch ala-tragus parallel to floor - mand arch
Rectangular collimation and fast film speed
Aluminum
Increase the exposure time

35. you notice that the xrays you process are becoming successively lighter than the quality control film you compare it to. What should you do
Film placed backwards
Patient positioning
Check the processing chemical - particularly the developer
Cut exposure time by 1/3

36. On a mandibular molar PA - Where is the mylohoid ridge located
Before fixing
2.5 mm
Extra oral
Highest of the 2 ridges - about the level of the cervical 3rd - behind the 2nd and 3rd molars

37. What would cause increased magnification - decreased resolution and edge sharpness
Increased focal spot size - decrease source-object distance - & increased object-film distance
Mandibular occlusal
Gray & Rad
As low as reasonably achievable

38. What parts of the x-ray machine are included in the anode circuit
Film badges
Copper stem - tungsten target - radiator
Increased focal spot size - decrease source-object distance - & increased object-film distance
Check the processing chemical - particularly the developer

39. which projection is used to view sinuses
Only when necessary to help the dentist diagnose and treat oral diseases; elective xrays should be postponed until after delivery
PANO
Duplicate - which will go to the insurance comp.; office keeps best copy
Highest of the 2 ridges - about the level of the cervical 3rd - behind the 2nd and 3rd molars

40. What is the source-skin distance of x-ray machine that operates at 75 kVp
5 mSv or .5 REM
Reg. replenishment and changing out expired solutiong with fresh chemicals at reg. intervals; monitor strength of chemicals on a daily basis
8-16 inches
Scatter/secondary radition

41. What Size film is used to take a BW on a 3 yr. old
No exposure to x-rays - electrical failure - malfunction of x-ray machine - or processing errors
#4
#0
2.75 inch

42. What is the annual MPD for radiation workers
Time b/w exposure and 1st clinically observable symptoms
8-16 inches
50 mSv or 5 REM
Release of electrons when a material such as tungsten is heated to incandescence - electrons are boiled off from the cathode filament in the x-ray tube when electric current is passed through it

43. Difference b/w direct and indirect exposure sensor?
Direct - directly obtaining a digital image by exposing intraoral sensor to x-rays to provide an image that can be viewed on a computer - indirect - photostimuable phosphor plate sensor technology - obtaining a digital image in which an exposed phosp
20 min
As low as reasonably achievable
Excessive vertical angulation

44. What should be done prior to ordering radiographs for a patient
20 min
Clinical exam
The mental ridge
Focal spot size - target-image receptor distance - object-image receptor distance - motion - screen thickness - screen-film contact - and crystal/pixel size of intraoral image receptors

45. you notice that a radiograph taken several months ago is brown and spotted. What happened
As close as possible
Insufficient or improper washing
As far as practical
Periapical

46. What causes teeth to appear very short and distorted
#4
Movement caused by the patient - slippage of the image receptor - or vibration of the tube head
Excessive VA w/ PID positioned too steep enough away from zero degrees
Copper stem - radiator and air space

47. What radiograph is used to sHow contrast in soft tissues
Insufficient or improper washing
As close as possible
MRI
#3

48. What is the major diff. b/w particulate and electromagnetic radiation
Occlucal
particulate radiation: made of protons - neutrons - electrons and alpha and beta particles; has mass -electromagnetic radiation: made of photons; no mass
Clear/blue in the area of overlap b/c fixer will not remove all crystals
Roentgen

49. Mand central anatomy
Genial tubercles - lingual foramen
The most distal tooth should be captured in full as well as a few mm of bone level behind the most distal tooth
underexposure-underdevelopment -depleted developer solution -excessive fixation (takes all crystals off)
Image the entire dentition - surrounding alveolar bone - sinuses - and the TMJ - examine large area of face and jaws - locate impacted teeth - retain root tips - evaluate trauma - lesions - and diseases - and assess growth and development

50. What types of cells must be effected in order for mutation to occur
Left side
Panoramic cape
Mental foramen - mental ridge - mand canal
Genetic cells