RAPHEX THERAPY CORE MAIN QUESTIONS AND ANSWERS SURE A.pdf

RAPHEX THERAPY CORE MAIN QUESTIONS AND
ANSWERS SURE A+
✔✔btw. universal and dynamic wedges, which requires more MU? - ✔✔Universal

✔✔btw universal and dynamic wedges, which makes a more penetrating depth dose? -
✔✔universal

✔✔for which does the wedge transmission factor vary with field size? universal or
dynamic? - ✔✔both

✔✔what is the WAHA equation? - ✔✔WA=(180-HA)/2

✔✔Equation for the gap on the skin surface for a pair of matched fields at some depth -
✔✔g=(d/SAD)*(C1+C2)/2

✔✔Equation for the RPO gantry angle given the LAO gantry angle -
✔✔RPO=LAO+180-(2xdivergence angle)

✔✔flattening filters flatten the beam at a depth of - ✔✔10cm

✔✔what two factors are important in selecting a PDD table from literature for a
superficial x-ray unit? - ✔✔HVL and SSD

✔✔dose under a 1.5cm width block of 5 HVL thickness in a 15x15 6MV photon beam at
5 cm depth due to transmission plus scatter is approximately ____% of the dose in the
open beam - ✔✔15%

✔✔A patient treated with 6MV tangential breast fields, the dose to the ovaries 20cm
inferior to the fields is approximately ___% of the prescribed dose - ✔✔.5%

✔✔how far from the field edge does 5% occur for a 6MV beam? - ✔✔2cm