Radiology Artifacts. Screen-Film Mammography

Radiology ArtifactsRadiology Artifacts

Screen-Film Screen-Film MammographyMammography

http://www.sma.org.sg/smj/http://www.sma.org.sg/smj/4707/4707pe1.pdf4707/4707pe1.pdf


Pressure Pressure mark or mark or crimp mark crimp mark due to due to excessive excessive pressure on pressure on film appears film appears as increased as increased optical optical density.density.




Artifacts caused by dust and dirt on intensifying screen creating white spots simulating calcifications


Screen-Screen-Film Film

MammograMammographyphy

Blurring due Blurring due to motionto motion






FingerprintsFingerprints

Screen-Film Screen-Film MammograMammogra

phyphy


phyphy



phyphy

Long streak of Long streak of stain on stain on intensifying intensifying screen screen appearing as appearing as minus densityminus density


phyphy


Obvious Obvious underexposure underexposure but not caused by but not caused by technique or technique or processingprocessing


phyphy

Two films Two films loaded into loaded into same cassettesame cassette


phyphy



phyphy

Wet or damp Wet or damp screen causing screen causing plus densityplus density


phyphy


Easy one. Easy one. Why is ID Why is ID superimposesuperimposed on breast?d on breast?


phyphy

Cassette Cassette loaded loaded backwards backwards (front-back) (front-back) into bucky into bucky tray.tray.


phyphy


Obvious Obvious underexposurunderexposure but not e but not caused by caused by technique or technique or processingprocessing


phyphy

Film loaded Film loaded upside down upside down into cassetteinto cassette


phyphy


Easy?Easy?


phyphy

Cassette Cassette loaded upside loaded upside down into down into bucky tray.bucky tray.


phyphy



phyphy

Light leak in Light leak in cassettecassetteIncompletely Incompletely latchedlatchedcrackcrack


phyphy



phyphy

Double Double exposureexposure


phyphy



phyphyCompression Compression paddle vertical paddle vertical section section (anterior lip)(anterior lip)


phyphy



phyphy

Films run Films run through through processor too processor too close together close together (overlapped)(overlapped)


phyphy



phyphy

Static Static electricityelectricity


phyphy



phyphy

Emulsion pick-Emulsion pick-off caused by off caused by pulling stuck pulling stuck films apartfilms apart


phyphy



phyphy

Black arrows Black arrows point at point at vertical black vertical black lines lines perpendicular perpendicular to direction of to direction of film travel film travel through through processor. processor. Cause: Cause: pressure from pressure from developer developer roller or roller or moisture on moisture on entrance entrance roller.roller.


phyphy



phyphy

Dust in Dust in darkroom and darkroom and dirty rollers dirty rollers causing causing emulsion pick-emulsion pick-off.off.


phyphy



phyphy

Over-Over-development development caused by caused by chemical fog.chemical fog.

RadiographRadiographyy

http://radiographics.rsnajnls.org/cgi/reprint/11/2/307?http://radiographics.rsnajnls.org/cgi/reprint/11/2/307?maxtoshow=&HITS=10&hits=10&RESULTFORMAT=&fulltemaxtoshow=&HITS=10&hits=10&RESULTFORMAT=&fulltext=grid+artifacts&andorexactfulltext=and&searchid=1&FIRxt=grid+artifacts&andorexactfulltext=and&searchid=1&FIR

STINDEX=0&sortspec=relevance&resourcetype=HWCITSTINDEX=0&sortspec=relevance&resourcetype=HWCIT

Two images Two images of same of same anatomy. anatomy. What What changed?changed?

RadiographRadiographyy

No gridNo grid102 cm SID102 cm SID.33R ESE.33R ESE

GridGrid122 cm SID122 cm SID

2.2 R ESE2.2 R ESE

CRCR

http://radiographics.rsnajnls.org/cgi/reprint/11/5/795?http://radiographics.rsnajnls.org/cgi/reprint/11/5/795?maxtoshow=&HITS=10&hits=10&RESULTFORMAT=maxtoshow=&HITS=10&hits=10&RESULTFORMAT=&fulltext=artifact&searchid=1&FIRSTINDEX=10&sort&fulltext=artifact&searchid=1&FIRSTINDEX=10&sort

spec=relevance&resourcetype=HWCITspec=relevance&resourcetype=HWCIT

What are What are white spots?white spots?

CRCR

Dust / dirt on Dust / dirt on phosphor phosphor screenscreen

CRCR



Dirt on CR plate. Right Dirt on CR plate. Right image repeated on image repeated on screen-filmscreen-film

Laser

Rotating

Mirror

Beam scanned

across film

PM Tube

Analog/ Digital

Computer

Light

Plate Travel

CRCR



What are What are white lines?white lines?

CRCR

Cracks on image plate due Cracks on image plate due to mechanical wearto mechanical wear

CRCR



CRCR

Transport Transport problems in CR problems in CR readerreader

Laser

RotatingMirror

Beam scannedacross film

PM Tube

Analog/Digital

Computer

Light

Plate Travel

CRCR



What are What are funny dark funny dark patterns on patterns on ventilator ventilator tube metal tube metal stabilizer?stabilizer?

CRCR

Moire effect Moire effect because of because of interference interference between scan between scan frequency of frequency of matrix and matrix and spiralspiral

CRCR



CRCR

Diagonal Diagonal collimation collimation caused caused algorithm to algorithm to improperly improperly recognize recognize collimated areacollimated area

CRCR



CRCR

Chest Chest incorrectly incorrectly specified by specified by technologist technologist to CR reader to CR reader as lumbar as lumbar spinespine

UltrasoundUltrasound

http://radiographics.rsnajnls.org/cgi/reprint/12/1/35?http://radiographics.rsnajnls.org/cgi/reprint/12/1/35?maxtoshow=&HITS=10&hits=10&RESULTFORMAT=&fulltexmaxtoshow=&HITS=10&hits=10&RESULTFORMAT=&fulltext=artifacts&andorexactfulltext=and&searchid=1&FIRSTINDEt=artifacts&andorexactfulltext=and&searchid=1&FIRSTINDE

X=0&sortspec=relevance&resourcetype=HWCITX=0&sortspec=relevance&resourcetype=HWCIT

There’s flow but it There’s flow but it isn’t showing up. isn’t showing up.

Why?Why?




Improper setting of velocity scale (set Improper setting of velocity scale (set too high). Low flow not displayedtoo high). Low flow not displayed




What’s that funny What’s that funny reversed flow?reversed flow?

UltrasounUltrasoundd

Improper setting of velocity scale (set Improper setting of velocity scale (set too low). Aliasing occurstoo low). Aliasing occurs




Low flow in both Low flow in both directions?directions?


Doppler angle is 90Doppler angle is 90oo; ; sample volume has sample volume has vessel perpendicular to vessel perpendicular to beam. Right image beam. Right image alters Doppler angle.alters Doppler angle.




Same anatomy. Why is there spectral Same anatomy. Why is there spectral broadening on the left image?broadening on the left image?


7171oo Doppler angle Doppler angle 8181oo Doppler angle Doppler angle

Minimize spectral Minimize spectral broadening artifact by broadening artifact by using Doppler angles < using Doppler angles <

6060oo

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Radiology Artifacts. Screen-Film Mammography