X-RAY BEAM QUALITY AND QUANTITY

Question 1

what are milliamperes(mA)

Answer 1

this affects the quantity of xray beams

this is because mA affects the heating current which in turn affects the amount of electrons travelling across the xray tube from the filament

the higehr the milliamperes are the more electrons there will hbe travelling across the xray tube

Question 2

what is kilovoltage (kv)

Answer 2

this describes the potential difference between the anode and cathode and determines the kinetic energy acquired by the electrons traveling across the tube.

a higher kv would increase:
- the photons energy
- beam quantity

Question 3

what is beam filtration

Answer 3

beam filtration filters out low energy photons which dont contribute to image quality and cause unecessary radiation to the patient

Question 4

explain the 2 ways in which beam filtration is achieved

Answer 4

inherent filtration - as the xray beam leaves the tube it does so via various components such as the tube housing, the oil and the tube window

additional filtration - the x ray beam passes through a sheet of alluminium which helps to remove any low energy xray photons leaving only the high energy ones