Topic 2

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Artifact analysis
 One of the causes of rejected images
listed in the repeat analysis worksheet
is the presence of image artifacts.
 An artifact can contribute significantly
to the total repeat rate; therefore a
thorough knowledge of artifacts and
their possible causes is necessary so
that corrective action can be taken.
What Is An Artifact?
 Any optical density
that is not anatomy
 An unwanted
density on the
radiograph
 Interferes with
diagnosis
There Are Three Time Periods
In Which Artifacts Can Occur
 During exposure
 During processing
1 1 3
 During film
handling, prior to
processing,
loading cassette, or
storing
Exposure Artifacts
 They are caused by the patient, the
technologist, or the equipment during a
diagnostic procedure
 Poor screen-film contact
 Improper use/positioning of a grid
 Double exposure
 Patient motion
 Poor patient preparation
 Clothing, jewelery, glasses, belts, etc.
Processing Artifacts
 They are caused by or occur during the
processing of diagnostic images
 Dirty Rollers



Will leave deposits on film
Areas of increased or reduced density
Occasionally some sludge may not be
washed off and dried onto the film
 Chemical Fog
 Improper or inadequate chemistry
 Leaves a uniform dull gray haze on the film
 May also be seen in two different colors
 Referred to as dichroic stain
Guide Shoe and Roller Marks
 Guide shoes are sprung or improperly
positioned
 The ridges in the guide shoe press against the
film leaving an artifact
 Pi-lines
 Dirt or stain on a roller
 3.14 inches apart
 Pressure marks
 Irregular or dirty rollers

Small, circular patterns are produced
Hypo Retention
 Yellowish stain that appears on finished
radiograph
 Due to inadequate washing
 Remaining thiosulfate from fixer solution
Handling And Storage
Artifacts
 They occur during darkroom handling
or during storage before use.
 Light or Radiation Fog
 White light streaks
 Safelight too close or wrong wattage
 Film left in x-ray room during
exposure
Kink Marks
 Improper handling or storage
 Appears as a fingernail mark
Static
 Caused by buildup of electrons in the emulsion
 Three types of static artifacts
 Crown
 Tree
 Smudge
FILMS STUCK TO EACH OTHER
DURING PROCESSING
HYPORETENTION
ROLLER MARKS
PI-LINE
GUIDE SHOE MARK
WATER STAIN
STATIC (Tree Static)
STATIC (Crown Static)
STATIC (Smudge Static
FINGER MARKS
CRIMPING MARK
CRIMPING MARK
PICK-OFF
WATER STAIN
WATER STAIN
MOTION
POOR FILM SCREN
CONTACT
ARTIFACT????
H.T. (high Voltage) CABLES
ROTATION + FOG
DOUBLE EXPOSURE
BACKSCATTER OR CASSETTE
UPSIDE-DOWN
BACKSCATTER
BACKSCATTER OR CASSETTE
UPSIDE-DOWN
MOIRE EFFECT
Are artifacts also called zebra pattern Artifact
It is a double set of grid lines caused by the
placement of a grid cassette in a Bucky tray.
WARPED CASSETTE-LIGHT LEAK
HAIR BUN
CLOTHES RIBBING
TUBE
HAIR STREAKING
GRID CUT-OFF
JEWELLERY
HEARING AID
LIGHTER IN THE POCKET
SCATTER FOG
SANDBAG
UMBILICAL RING
AIR IN THE VENTRICLES
AIRHEAD?????
PLASTER
DIRT ON THE SCREEN
PATHOLOGY
FOGGING
KYPHOSIS-CHIN
STRAP
SCRATCHES
STATIC
Intra Uterine Device
Chole clips
Earring Artifact
Patient Movements
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