Contrast

kVp - kilovoltage peak is the MAJOR factor in overall contrast and determines quality of beam. Increasing kVp decreases image contrast.

grids - reduces scatter radiation. As the grid ratio increases, the contrast also increases.

OID - when the object to image distance increases so does contrast (small factor). Air gap technique.

beam restriction - collimation increases contrast

filtration - removes low energy x-rays and increased filtration decreases overall contrast

body part/pathology - thicker body parts or denser tissue decrease contrast

Density

kVp - kilovoltage peak is a lesser factor in density and follows the 15% Rule. A 15% increase in kVp will yield twice the density.

mAs - millamperage per second is the MAJOR factor in controlling density.

SID - source to image distance follows inverse square law. Double the SID and the image density will be reduced by 1/4 (25%).

anode heel effect - decreases density for body parts under the anode and increases density for parts under the cathode

beam restriction - collimation decreases density

body part thickness/pathology - thicker body parts and denser tissue from pathology will decrease density

filtration - removes low energy x-rays and increasing filtration decreases density

grids - decrease overall density

Distortion

tube angle - minimize Shape distortion by keeping the beam centered on the body part

body part angle - minimize Shape distortion by keeping the body part perpindicular to the central ray

IR angle - minimize Size distortion by keeping OID low, and minimize Shape distortion by keeping image receptor perpindicular to central ray

SID - major factor for Size distortion or magnification and standard protocols should be followed to minimize.

OID - high object to image distance produces Size distortion or commonly termed magnification

body part thickness - using the anode heel effect place the thicker section of body part toward cathode end to minimize Size Distortion (magnification)

Recorded Detail - Spatial Resolution

Angle - keeping the central ray perpindicular to the body part contriubtes to best recorded detail

motion - patient motion causes blurring and reduces detail

focal spot size - smaller focal spot(smaller filament) size yields better recorded detail and large focal spot increases blur

SID - greater SID improves recorded detail

OID - when Object to Image distance increases the recorded detail decreases. When OID decreases then recorded detail is improved.

body part thickness - body part thickness can increase OID and reduce detail/sharpness

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Radiographic Image Quality Factors