Chapter 19 Screen-Film Image Artifacts Usually TECHNOLOGIST dependant Patient Preparation – Clothes left on (zippers, jewelry, dentures – Positioning errors (patient, tube, bucky, receptor) – Wrong screen-film combination (detail screens with fast film and vice-versa) – “Bling” left on

Processing Artifacts Roller marks; guide shoe lines, Pi lines Dirty rollers (curtain effect/run down, etc.) Chemical fog Wet-pressure sensitization (varied amount of pressure on the rollers = uneven film “splotches”)

Handling Artifacts Light/radiation fog Kink marks Static (tree, smudge are the most common) Hypo retention (fixer retention – required for mammo)

Chapter 20 Film-Screen Quality Control Quality Assurance is a JCAHO required 10 step PEOPLE PROCESS! Quality Control = imaging instrumentation and equipment process

QC = 3 step process Acceptance testing Routine performance monitoring Maintenance

Radiography QC Filtration – annually Collimation – semiannually (+/- 2% SID) F.S. size – Annually (+/-50%) FREQUENTLY MISSED PARAMETER! kVp calibration – Annually (+/- 10%) Exp. Timer accuracy – annually (based on mS used – more leeway with longer exposures) Linearity – annually (+/- 10%) of same mAs with DIFFERING mA/times Exp. REPRODUCEIBILITY – SAME contrast/density, etc with SAME exp. factors repeated later on

Focal Spot Size Check Tools Pin hole camera (somewhat hard to use?) Star pattern (down to.3mm sizes) Slit camera – preferred method

Other RAD QC Filtration Collimation (PBL) kVp/Timer Exposure Linearity (same mAs with VARIED mA and times) Intensifying screens Protective apparel (annually) Film illuminators

Fluoro QC Exposure rate (max table top dose/min) Spot film exposures Automatic Exposure System (ABS/ABC – AEC)

Tomo QC Tube travel/ ARC Fulcrum level Patient exposure

Processor QC See Table 20-6 for QC RAD Processor items/intervals Processor Maintenance – Scheduled maintenance – Preventative maintenance – Nonscheduled maintenance

Processor Monitoring Temperatures Replenishment Sensitometry/Densitometry