Image Production and Evaluation NOTE: QA AND QC ARE USED INTERCHANGABLY IN APPLETON AND LANGE

Intensifying screen Base Reflective layer Active Layer Protective layer

Intensifying.Screen: Detail and speed Thicker the active layer: less detail and more speed Larger the phospher:less detail and more speed Formula: old screen new screen

Digital Imaging PSP CRT ADC IP CR DR FOV field of view or how much of the patient is included in the matrix Matrix-rows and columns of pixels (512 x512) Pixel size As matrix increase, pixel size decreases As FOV increases, pixel size increases As pixel size increases, resolutions decreases

TARGET ANGLE LINE FOCUS PRINCIPLE PG. 56 in, Mosby Actual Effective Large angle small angle anode heel

MAMMOGRAPHY Use very low KVP 23-28 molybdenum targets High MAS

PROCESSING

DEFINE EXIT (REMNANT RADIATION) LATENT IMAGE MANIFEST IMAGE

Magnification: FOR EVERY 1” OF OID INCREASE, SID MUST INCREASE BY 7” WALLACE PG 27-33 Mag. Factor - SID SOD SOD ---- SID - OID IMAGE SIZE -image = SID object SOD % OF MAG- OID SOD X 100 #s 45 57,93

DENSITY OD or Logarithm of opacity Ratio of amount of light incident on film to the amount of light transmitted thru film (Mosby, pg. 53) Controlling factors mAs kVP Distance Film/screen Grids Collimation Anatomy/pathology Anode Heel Filtration

Detail Focal spot size Screen speed SID OID Motion artifact

CONTRAST KVP GRID FIELD SIZE Filtration Anatomy and pathology HIGH, SHORT LOW, LONG

CHARACTERISTIC/H&D CURVE PG 58 MOSBY Exposure error latitude Contrast latitude speed of film base/fog processing

DIFFERENTIAL ABSORPTION & ATTENUATION Difference between x-rays absorbed through photoelectric effect and those not absorbed at all.

Quantum Mottle Mottled appearance (looking through a mist) low mas-increase QM high speed film- increase QM

GRIDS GRID RATIO: HEIGHT DIVIDED BY DISTANCE AFFECT ON CONTRAST MULTIPLYING FACTOR GRID CUTOFF

FOCAL SPOT/ BLUR Umbra/penumbra or focal spot blur Small FS = less Large FS = more Increased SID = less decreased SID = more increased OID = more decreased OID = less

FILM CONSTRUCTION (Pg. 166-167 Bushong)/Cassette BASE EMULSION

INTERACTIONS CHARACTERISTIC COMPTON INFRARED CLASSICAL, THOMSON, COHERENT PHOTOELECTRIC BREMSTRAULING PAIR PRODUCTION PHOTO-DISINTEGRATION

Technique and Exposure