Artifact analysis Artifact analysis One of the causes

Artifact analysis

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 �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

Processing Artifacts

FILMS STUCK TO EACH OTHER DURING PROCESSING

HYPORETENTION

ROLLER MARKS

PI-LINE

GUIDE SHOE MARK

WATER STAIN

Handling Artifacts

STATIC (Tree Static)

STATIC (Crown Static)

STATIC (Smudge Static

FINGER MARKS

CRIMPING MARK

CRIMPING MARK

PICK-OFF

WATER STAIN

WATER STAIN

Exposure Artifacts

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

In CT Scan Artifacts

Intra Uterine Device

Chole clips

Earring Artifact

MRI artifacts

Patient Movements