Artifacts

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Artifacts

Any irregularity on an image that is not caused by the proper shadowing of tissue by the primary beam

Three classifications

Storage and handling artifacts

Exposure artifacts

Processing artifacts

Processing Artifacts

Most of the artifacts that occur during processing are caused by the transport system of the processor, and are of the pressure-type that sensitize the emulsion and appear as higher optical density

Roller marks

Guide shoe marks occur when the guide shoes are sprung or incorrectly positioned and are found on the leading or the trailing edges of the film parallel to the direction of film travel through the processor

Dirty Rollers

Dirty or warped rollers can cause "emulsion pick-off" and or "gelatin buildup, which results in "sludge" deposits on the film

Chemical Fog

Usually results from incorrect or inadequate processing chemistry or processing technique

Wet-Pressure Sensitization

A common artifact that is produced in the developing tank

Irregular or dirty rollers cause pressure during development and produces small circular patterns of OD

QUESTION: What are the three general areas of artifact classification?

ANSWER: Processing, exposure, and handling and storage artifacts.

Image fog

Caused by the temperature or the humidity being too high

Prevention--store films in a cool, dry place at optimum conditions

68 degrees F or lower
30-60% relative humidity

Pressure marks

Pressure marks can occur if the film is stacked too high

Light or radiation fog

White-light leaks in the darkroom or within the film cassette causes streak-like artifacts of increased OD

Hypo Retention

A yellow-brown stain appears on the film after a long storage period indicating a problem with hypo retention from the fixer

Static

Cause by a buildup of electrons in the emulsion and is most noticeable during winter or periods of extremely low humidity

Three distinct patterns: crown, tree, and smudge

Crown static

resembles a crown

Tree static-

-tree or bush-like with fingerlike processes emanating outward from point of discharge

Smudge static-

assumes characteristic of black smudges

Handling and Storage Artifacts (Static) **Prevention

Clean intensifying screens regularly with commercial electrostatic cleaner solution recommended by the manufacturer

QUESTION: What are the ideal storage conditions for radiographic film?

ANSWER:
68 degrees F
and 30-60%
relative
humidity.

Kink marks (crescent or crinkle marks)

Artifacts (kink marks or scratches) can be caused by incorrect or rough handling during loading and unloading film cassettes or storage either before or after processing

crescent or crinkle marks)

Appearance is semi-circular in shape (half-moon)

Film is bent around tips of fingers

Emulsion is damaged

QUESTION: What are the three types of static artifacts?

ANSWER: Crown, tree, and smudge.

QUESTION: What is the most common type of artifact and how do we prevent its occurrence?

ANSWER: Crescent or crinkle marks. It is prevented by properly handling x-ray film when loading and unloading cassettes.

Artifacts associated with how the radiographer conducts the examination

Incorrect screen-film match

Poor screen-film contact

Warped cassette

Incorrect positioning of the grid

Patient preparation

Screen-film match

Radiographic film and intensifying screens are designed to complement each other and to produce the highest quality image with the lowest patient radiation exposure

Mismatching of film and screens often increases patient radiation dose

Screen-film contact

Intensifying screens are designed to so that each sheet of film can be sandwiched tightly between them

Poor film-screen contact can produce lack of detail

Warped Cassette

Cassette backs and fronts may warp due to incorrect storage or traumatic handling

A warped cassette can cause a loss of contact between the film and intensifying screens causing a diverging of the light photons from the screens causing a loss of detail and contrast

Incorrect grid positioning

Correct tube/grid alignment is essential to prevent the undesirable absorption of primary radiation known as "grid cut-off"

Patient preparation

Patient preparation is essential for producing artifact-free images

QUESTION: What is the primary cause for a blurred image artifact?

ANSWER: Patient movement during film exposure

Automatic Processing Artifacts

Most of the artifacts that occur during processing are caused by the transport system of the processor, and are of the pressure-type that sensitize the emulsion and appear as higher optical density

Roller marks
**Guide shoe marks

Guide shoe marks occur when the guide shoes are sprung or incorrectly positioned. The marks are found on the leading or the trailing edges of the film they are straight and run parallel in the direction of film travel through the processor

Dirty rollers

Dirty or warped rollers can cause "emulsion pick-off" and /or "gelatin buildup, which results in "sludge" deposits on the film

Chemical fog

Usually results from incorrect or inadequate processing chemistry or processing technique

Wet-pressure sensitization

A common artifact that is produced in the developing tank

Irregular or dirty rollers cause pressure during development and produces small circular patterns of OD

Manual Processing Artifacts

Using manual processing it takes approximately one hour to prepare a completely dry and ready-to-read radiograph

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