Film Critique
Artifacts and Quality Management
Curtain Effect – solution dripping or “running down” a film can form patterns on the film that resemble a curtain.
Chemical Fog – overdevelopment of film usually caused by developer temperature being too high. It can also be caused by developer time, pH, or concentration above manufacturer’s recommendations.
Guide Shoe Marks – scratches on the film made by the jagged edges of the guide shoes. They may have become worn out, bent, damaged, or incorrectly installed or adjusted. They typically have sharp edges on the film.
Pi Lines – occur relative to the circumference of a roller and so occur at regular intervals. They run perpendicular to the direction of film travel, and are present due to dirt or chemical stains which sensitize the emulsion. They typically have a smudged appearance on the film.
Streaking – uneven development of an image that can be caused by failure of circulation system of the automatic processor.
Hesitation Marks (stub lines) – stripes of decreased optical density where rollers are left in contact with the film and further development is prevented. This happens most frequently with film jams or loss of power during processing.
Water spots – occur when liquid comes in contact with the unexposed image. A “splash” appearance with increased optical density becomes evident.
Water pressure sensitization – dark lines in the direction of the rollers appear when water comes in contact with the grooves on the rollers prior to film processing. The pressure of the rollers imprint their grooves on the film.
Hyporetention – white powdery residue that remains on the film surface due to incomplete washing.
Grid lines – shadows of lead strips that appear caused by the failure of the grid to move during exposure, improper grid-focusing distance, improper angulation of the central ray, or improper centering.
Grid cutoff – decreased optical density caused by primary radiation being absorbed when the grid is backwards
Moire effect – zebra pattern artifact that occurs when using a grid cassette in the bucky.
Tree static – caused by low humidity conditions in the processing area.
Crown static – radiates in one direction resulting from friction while pulling on the film.
Smudge static – dark areas where excessive amounts of light have exposed the film and is usually caused by rough handling of the film in the processing area.
Crescent marks – dark half-moon marks caused by bending the film prior to processing. You may also see light half-moon marks by bending the film after development. This removes silver from the film, decreasing optical density.
Debris on Image receptor – appear as irregular-shaped radiopaque structures. You will typically see these on multiple films when using the same cassette.
Electronic processing failure – appears on CR or DR when the computer attempts to assign an adequate gray-scale, and the part is not centered properly. Exposure indexes are usually high, and it is difficult to adjust window/level to diagnostic quality.
Underexposure (CR/DR) – causes a loss of contrast in dense anatomy and a grainy appearance.
Double exposure – occurs when technologist mixes up cassettes. Radiograph is usually high density, and possesses overlapping images.
Poor film-screen contact – most of the radiograph appears optimal, but a particular region may appear blurry.
General artifacts – anything that appears on the film other than the pertinent anatomy. This can range from jewelery to skin folds, hair, prosthetic devices, etc.