This document discusses various types of artifacts that can appear on radiographic images, degrading image quality and affecting interpretation. It describes pre-exposure artifacts from film handling and storage issues, positioning artifacts from improper patient placement or equipment use, exposure artifacts involving radiation factors, and post-exposure artifacts in film processing. Specific examples are given for each type like pressure marks, scratches, static electricity streaks, magnification errors, motion blur, over/under development, incomplete fixing, and digital transfer or processing issues. The artifacts can mimic pathology, reduce diagnostic value, or lead to misinterpretation if not recognized.

1. Presented by
Dr Ajith Y. MVSc
Division of Medicine
IVRI, Izatnagar, UP, India

2. Any appearance/opacity on a radiograph
which doesn’t represents an actual anatomic
structure within the patient being
radiographed.

4. • Degrades quality of radiograph and affect
interpretation.
- Cause visual distractions for the radiologist
leading to misrepresentation of an actual
anatomic structure
- Can mimic pathology
• Render a radiographic study non-diagnostic

5. Post
exposure
Exposure
Pre
exposure

6. A. Pre exposure artifacts (Film storage and Handling)
Pressure
Abrasions & Scratches
Fingerprints
Static electricity
Material in cassette
Light leak

7. • Pressure
- Black Crescents Marks
- Due to rough handling and bending of film.

8. • Abrasions & Scratches
- Black: pressure from abrasion activates crystals
- White: emulsion has been removed (scratch)
- Due to rough handling

9. • Fingerprints
- Black: Developer on fingertips
- White: Oil or Fixer on fingertips blocks developer
- Keep fingers dry and clean
- Touch only film edges

10. • Static electricity (ARBORESCENT STREAK)
- Two patterns: Branching and Smudge / spot
- Cause: Static electricity by friction/ due to low humidity
- Avoid friction and provide moderate humidity

11. • Material in cassette
- X rays are prevented from
reaching film
- Common cause: Hair; dust

12. • Light leak
- A form of fog
- Cassette not closed properly
- Safelight filter crack

13. B. Positioning
• Magnification
• Foreshortening / distortion
• Patient rotation
• Upside-down cassette
• Grid cut off

14. • Magnification
• Object closer to film:
– Closer to normal size
– Sharper margins
• Object far from film:
– Magnified
– Less distinct margins

15. • Foreshortening / distortion
- X-ray beam does not pass
perpendicular to long axis
of structure
- Differential magnification of
structure
Unequal
magnification

16. • Patient rotation
- A form of distortion.
- Lesions may be masked by
atypical superimposition on
normal anatomy.
Summation shadow of penis over caudal lumber vertebras

17. • Upside-down cassette
- White & focal: Springs & latches on back of cassette
block x-ray beam
- Global lightness: Lead backing absorbs some x-rays
(film appears underexposed)

18. • Grid cut off
- Grid is not aligned with beam
- Loss of primary radiation as a
result of undesirable absorption.
- Too light and less contrast image

19. • Grid cut off

20. C. Exposure artifacts
• Motion
• Double exposure
• Overexposure
• Underexposure
• Material obstructing x-ray beam

21. • Motion
- Blurred image
- Poor clarity
- Less sharp edges
- Non-sedated animal
- Panting
- Prevention
Sedation
Restrain
Stable Cassette
Stable X ray unit

22. • Double exposure
- Film is darker than a single exposure
- Same image: Double click
- Two separate image: Already exposed film

23. • Over exposure
- Too high mAs or kVp
- Body size low
- Decreased FFD
- Over development

24. • Under exposure
- Too low mAs or kVp
- Body size high
- Increased FFD
- Under development
- Two films in cassette

25. • Material obstructing x-ray beam
- Radiopaque structure
- Dust particles
- On or in patient
- Above cassette

26. D. Post exposure artifacts (Film processing)
 Overdevelopment
 Underdevelopment
 Insufficient mixing
 Incomplete fixation
 Incomplete washing
 Frosty area on film
 Finger marks
 Dark line on top
 White line on top
 Blank film
 Chemical fog

27. • Overdevelopment
- Black & global
- Cause: Too much metallic
Ag forms in emulsion
- Developer too hot
- Developed too long

28. • Underdevelopment
- White & global
- Cause: Too little metallic
Ag forms in emulsion
- Developer too cold
- Developed too little time

29. • Uneven development
• Chemical levels are uneven: affect developing and fixing
• Top of the film.
- White horizontal area on top of the film
- Dark horizontal area on top of the film
• If the chemicals are not stirred prior to use.

30. • Unevenly developed
Uneven Chemical Levels
not exposed, is developed,
and not fixed
exposed, developed, and
fixed
not exposed, developed,
and partially fixed
not exposed, but is
developed and fixed

31. • Insufficient mixing
- White streaky appearance
over the entire film.

32. • Incomplete fixation
- Initially film is cloudy and milky
- Over time appears yellow/brown –Dichroic stain
-

33. • Incomplete washing
- Fixer remains
– Cloudy, sticky residue
– Yellow-brown stain
– Sulfur smell

34. • Fog
-Increased blackness
- Regional or global
- Definition: any
unwanted film
exposure /development
- Decreased image
contrast and detail

35. • Fog: causes
- Excessive pressure
- Heat- film should be stored at <68 F
- Light- from outside source or safelight
- Humidity- should be 30-50%
- Chemical- over developing
- Old film
- Certain gases
- Scatter radiation

36. E. Artifacts in Digital/Computerised radiography
• Cassette Debris
• Faulty Transfer
• Uberschwinger or rebound effect

37. • Faulty transfer
- Distorted appearance
- Problems in data transfer

38. • Uberschwinger or rebound effect.
• Black lines occur around dense structure border
– Can be mistaken for loosening or infection of
implants
• Cause: Certain processing algorithms (edge
enhancement)

39. • Uberschwinger or rebound effect.