factors that affect the quality and quantity of Xray beam
Quantity refers to the number of photons produced during an exposure. Factors affecting the quantity of a beam include
Peak kilo voltage kVp- An increase in peak kilovoltage increases the quantity of Xrays while a decrease decreases the beams’ quantity.
Tube current mA- An increase in tube current increases the quantity of extra beam while a decrease also decreases the quantity
The quantity of Xrays is directly proportional to tube current and exposure time
An increase in voltage ripple decreases quantity while a decrease increases the quantity
An increase in target atomic number z- increases the quantity while a decrease decreases the quantity
Factors affecting the quality of x-ray beam
quality relates to the x-ray spectrum changes and the effective photon energy.
An increase in peak kilovoltage increases the quality of the x-ray beam while decreases the quality of the Xray beams
An increase in target atomic number z- increases quality while a decrease decreases the quality
An increase in voltage ripple decreases quality while a decrease increases the quality
What effect does increasing mAs and kVp have on the total x-ray emission spectrum?
When mAs is changed, the result is a change in the amplitude of the emission graph.
When kVp is changed, the result is a change in the # of higher-energy photons and the emission graph’s amplitude.
What is the relationship between the kilovoltage peak and the photons’ average energy (keV) in the primary beam?
The avg of Kev of the photons is 30-40% of the kVp